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Farzin P, Hajiahmadi MJ, Soleimani M. Multi-channel polarization manipulation based on graphene for encryption communication. Sci Rep 2024; 14:11155. [PMID: 38750175 PMCID: PMC11096339 DOI: 10.1038/s41598-024-61323-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Accepted: 05/03/2024] [Indexed: 05/18/2024] Open
Abstract
Wave-based cryptography, at the vanguard of advancing technologies in advanced information science, is essential for establishing a diverse array of secure cryptographic platforms. The realization of these platforms hinges on the intelligent application of multiplexing techniques, seamlessly combined with appropriate metasurface technology. Nevertheless, existing multi-channel encryption technologies based on metasurfaces face challenges related to information leakage during partial channel decoding processes. In this paper, we present a reprogrammable metasurface for polarization modulation. This metasurface not only allows for the arbitrary customization of linearly polarized reflected waves but also enables real-time amplitude modulation. Here, relying on polarization amplitude control, a fully secure communication protocol is developed precisely in the terahertz (THz) spectrum to achieve real-time information encryption based on polarization modulation metasurfaces where access to information is highly restricted. The proposed metasurface employs the double random phase encryption (DRPE) algorithm for information encryption. It transmits the encrypted data through different polarization channels using two graphene nanoribbons, exclusively controlled by external biasing conditions. Various encryption scenarios have been outlined to fortify information protection against potential eavesdroppers. The simulated results show that this unique technology for hiding images by manipulating the polarization of the reflected wave provides new opportunities for various applications, including encryption, THz communications, THz secure data storage, and imaging.
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Affiliation(s)
- Parsa Farzin
- School of Electrical Engineering, Iran University of Science and Technology, Tehran, 1684613114, Iran
| | - Mohammad Javad Hajiahmadi
- School of Electrical Engineering, Iran University of Science and Technology, Tehran, 1684613114, Iran.
| | - Mohammad Soleimani
- School of Electrical Engineering, Iran University of Science and Technology, Tehran, 1684613114, Iran
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2
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Wang T, Yang Z, Li T, Yao H, Lu Y, Yan X, Cao M, Yang M, Liang L, Zheng W, Wu X, Yao J. Ultrasensitive optical modulation in hybrid metal-perovskite and metal-graphene metasurface THz devices. OPTICS EXPRESS 2023; 31:20080-20091. [PMID: 37381409 DOI: 10.1364/oe.487640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 05/07/2023] [Indexed: 06/30/2023]
Abstract
Implementation of efficient terahertz (THz) wave control is essential for THz technology development for applications including sixth-generation communications and THz sensing. Therefore, realization of tunable THz devices with large-scale intensity modulation capabilities is highly desirable. By integrating perovskite and graphene with a metallic asymmetric metasurface, two ultrasensitive devices for dynamic THz wave manipulation through low-power optical excitation are demonstrated experimentally here. The perovskite-based hybrid metadevice offers ultrasensitive modulation with a maximum modulation depth for the transmission amplitude reaching 190.2% at the low optical pump power of 5.90 mW/cm2. Additionally, a maximum modulation depth of 227.11% is achieved in the graphene-based hybrid metadevice at a power density of 18.87 mW/cm2. This work paves the way toward design and development of ultrasensitive devices for optical modulation of THz waves.
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3
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Selected Applications of Terahertz Pulses in Medicine and Industry. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12126169] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
This article contains a brief summary of areas where terahertz technology is making an impact in research and industrial applications. We cover some of its uses in the pharmaceutical setting, where both imaging and spectroscopy play important roles. Medical applications are also being pursued in many research laboratories, primarily for imaging purposes and following on from the first results just over 20 years ago. The three-dimensional imaging capability of pulsed terahertz allows for the observation of tumours below the surface of tissue, such as basal cell carcinoma of skin. The recent use of the technology in studies of cultural heritage has shown to increase our understanding of the past. The power of terahertz is exemplified by the discussion on its importance in different industries, such as semiconductor circuit manufacturing and automotive assembly.
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4
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Shi Z, Zhang H, Khan K, Cao R, Zhang Y, Ma C, Tareen AK, Jiang Y, Jin M, Zhang H. Two-dimensional materials toward Terahertz optoelectronic device applications. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C: PHOTOCHEMISTRY REVIEWS 2022. [DOI: 10.1016/j.jphotochemrev.2021.100473] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Tarabichi S, Al-Raeei M, Solieva O. Improving the accuracy of tumor surgery by THz imaging and making the results of pathological anatomy faster by THz spectroscopy. BENI-SUEF UNIVERSITY JOURNAL OF BASIC AND APPLIED SCIENCES 2022. [DOI: 10.1186/s43088-022-00201-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
The terahertz radiation is a specific part of the electromagnetic radiation spectrum and has multiple significant applications in multiple scientific researches such as the applications in the medicine. An important application of the terahertz is its use in tumor imaging which is very important in the tumor surgery; however, lots of physicians and workers in the medical field have little information or having no information at all, dealing with this significant part of the electromagnetic spectrum.
Results
In this work, we interviewed a number of local surgeons in Syrian Arab Republic, who reported that they visually delineate the contour of tumors to be removed, and in order to reduce the number of future possible interventions, a large margin of healthy tissue is often excised. Furthermore, a number of pathologists who reported that preparing samples of excised tissues for examination takes a long period of time which may extend to several days, and that the results of histopathology indicate in some cases the integrity of removed tissues.
Conclusion
We have found that a significant number of participants in the survey demonstrated that the importance of dealing with terahertz imaging and terahertz spectroscopy, encouraging to implement the technique in the Syrian Arab Republic.
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6
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Abstract
Proteins play a key role in living organisms. The study of proteins and their dynamics provides information about their functionality, catalysis and potential alterations towards pathological diseases. Several techniques are used for studying protein dynamics, e.g., magnetic resonance, fluorescence imaging techniques, mid-infrared spectroscopy and biochemical assays. Spectroscopic analysis, based on the use of terahertz (THz) radiation with frequencies between 0.1 and 15 THz (3–500 cm−1), was underestimated by the biochemical community. In recent years, however, the potential of THz spectroscopy in the analysis of both simple structures, such as polypeptide molecules, and complex structures, such as protein complexes, has been demonstrated. The THz absorption spectrum provides some information on proteins: for small molecules the THz spectrum is dominated by individual modes related to the presence of hydrogen bonds. For peptides, the spectral information concerns their secondary structure, while for complex proteins such as globular proteins and viral glycoproteins, spectra also provide information on collective modes. In this short review, we discuss the results obtained by THz spectroscopy in the protein dynamics investigations. In particular, we will illustrate advantages and applications of THz spectroscopy, pointing out the complementary information it may provide.
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7
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Liu K, Zhang R, Liu Y, Chen X, Li K, Pickwell-Macpherson E. Gold nanoparticle enhanced detection of EGFR with a terahertz metamaterial biosensor. BIOMEDICAL OPTICS EXPRESS 2021; 12:1559-1567. [PMID: 33796372 PMCID: PMC7984768 DOI: 10.1364/boe.418859] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/11/2021] [Accepted: 02/11/2021] [Indexed: 05/25/2023]
Abstract
The epidermal growth factor receptor (EGFR) plays an important role in the proliferation of various cancers, and the expression level of EGFR in tumor tissues can provide a basis for the diagnosis and prognosis. Improving the detection technology of EGFR to achieve high sensitivity and faster speed will benefit the diagnosis of many types of tumors. Trace biological samples can be sensitively measured with terahertz (THz) metamaterial devices. Here, a bow-tie array THz metamaterial biosensor is presented and modified with gold nanoparticles (GNPs) and EGFR antibodies for specific EGFR detection. The effect of the size of the GNP on the sensitivity enhancement was also analyzed. Enhanced sensing for EGFR was achieved with the assistance of GNPs and EGFR antibodies. Importantly, the metamaterial functionalized by GNPs and antibodies with a bigger GNP diameter achieves a greater resonance frequency shift. The proposed metamaterial biosensor can also realize tiny-volume EGFR solution detection. Our proposed technique can therefore sense EGFR sensitively with high speed, and can potentially be applied to achieve quick and accurate detection of EGFR related tumors.
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Affiliation(s)
- Kai Liu
- Department of Electronic Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China
| | - Rui Zhang
- Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, Guangdong Province, China
| | - Yao Liu
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China
| | - Xuequan Chen
- Department of Electronic Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China
| | - Kaidi Li
- Department of Electronic Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China
| | - Emma Pickwell-Macpherson
- Department of Electronic Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong, China
- Department of Physics, University of Warwick, Coventry, United Kingdom
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Li X, Yin W, Khamas S. An Efficient Photomixer Based Slot Fed Terahertz Dielectric Resonator Antenna. SENSORS 2021; 21:s21030876. [PMID: 33525561 PMCID: PMC7866193 DOI: 10.3390/s21030876] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/21/2021] [Accepted: 01/25/2021] [Indexed: 02/01/2023]
Abstract
A slot fed terahertz dielectric resonator antenna driven by an optimized photomixer is proposed, and the interaction of the laser and photomixer is studied. It is demonstrated that in a continuous wave terahertz photomixing scheme, the generated THz power is proportional to the 4th power of the surface electric field of photocondutive layer. Consequently, the optical to THz conversion efficiency of the proposed photomixer has an enhancement factor of 487. This is due to the fact that the surface electric field of the proposed photomixer with a 2D-Photonic Crystal (PhC) superstrate has been improved from 2.1 to 9.9 V/m, which represents a substantial improvement. Moreover, the electrically thick Gallium-Arsenide (GaAs) supporting substrate of the device has been truncated to create a dielectric resonator antenna (DRA) that offers a typical radiation efficiency of more than 90%. By employing a traditional coplanar strip (CPS) biasing network, the matching efficiency has been improved to 24.4%. Therefore, the total efficiency has been considerably improved due to the enhancements in the laser-to-THz conversion, as well as radiation and matching efficiencies. Further, the antenna gain has been improved to 9dBi at the presence of GaAs superstrate. Numerical comparisons show that the proposed antenna can achieve a high gain with relatively smaller dimensions compared with traditional THz antenna with Si lens.
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Affiliation(s)
- Xiaohang Li
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S10 2TN, UK;
- Correspondence:
| | - Wenfei Yin
- School of Computer Science and Information Engineering, Hefei University of Technology, Hefei 230009, China;
| | - Salam Khamas
- Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S10 2TN, UK;
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9
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Abstract
This review considers glioma molecular markers in brain tissues and body fluids, shows the pathways of their formation, and describes traditional methods of analysis. The most important optical properties of glioma markers in the terahertz (THz) frequency range are also presented. New metamaterial-based technologies for molecular marker detection at THz frequencies are discussed. A variety of machine learning methods, which allow the marker detection sensitivity and differentiation of healthy and tumor tissues to be improved with the aid of THz tools, are considered. The actual results on the application of THz techniques in the intraoperative diagnosis of brain gliomas are shown. THz technologies’ potential in molecular marker detection and defining the boundaries of the glioma’s tissue is discussed.
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10
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Fang J, Zhang Z, Bo Y, Xue J, Wang Y, Liu J, Qin J, Hong Z, Du Y. Vibrational spectral and structural characterization of multicomponent ternary co-crystal formation within acetazolamide, nicotinamide and 2-pyridone. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2021; 245:118885. [PMID: 32920445 DOI: 10.1016/j.saa.2020.118885] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/25/2020] [Accepted: 08/25/2020] [Indexed: 06/11/2023]
Abstract
Ternary co-crystal, as a novel co-crystal design strategy developed on the basis of binary co-crystal, could be used to improve the physicochemical properties of active pharmaceutical ingredients (APIs) efficiently. However, it is difficult to obtain specific ternary co-crystals since such ternary one involves complex assembly of three different molecules. There are few reports on the micro-molecular structure respect of specific ternary co-crystal systems. In present work, 1:1:1 ternary co-crystal between acetazolamide (ACZ), nicotinamide (NAM) and 2-pyridone (2HP) has been synthesized successfully by mechanical grinding approach, and their structures are investigated by terahertz time-domain spectroscopy (THz-TDS) and Raman spectroscopy combined with theoretical calculation at the molecular level. The experimental THz spectral results showed that ACZ-NAM-2HP ternary co-crystal and the starting parent materials exhibited a few distinct spectral features in frequency-domain absorption spectra. Likewise, the Raman spectral result also shows some difference between the co-crystal and starting raw materials. Through density functional theory (DFT) calculations, the theoretical THz/Raman spectra and vibrational modes of two kind of possible ternary co-crystal theoretical forms (form I and II) between ACZ, NAM and 2HP were obtained. By comparing experimental and theoretical spectral results, the most suitable structure and vibrational modes of ACZ-NAM-2HP ternary co-crystal were determined. These results provide a wealth of information and unique method for studying molecular assembly and also inter-molecular interactions in specific ternary co-crystals at the molecular level in the emerging pharmaceutical co-crystal fields.
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Affiliation(s)
- Jiyuan Fang
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Ziming Zhang
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Yanhua Bo
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Jiadan Xue
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Yaguo Wang
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Jianjun Liu
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Jianyuan Qin
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Zhi Hong
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China
| | - Yong Du
- Centre for THz Research, China Jiliang University, Hangzhou City, Zhejiang Province 310018, PR China.
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11
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Bennett JW, Raglione ME, Oburn SM, MacGillivray LR, Arnold MA, Mason SE. DFT Computed Dielectric Response and THz Spectra of Organic Co-Crystals and Their Constituent Components. Molecules 2019; 24:molecules24050959. [PMID: 30857228 PMCID: PMC6429106 DOI: 10.3390/molecules24050959] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/26/2019] [Accepted: 03/04/2019] [Indexed: 11/26/2022] Open
Abstract
Terahertz (THz) spectroscopy has been put forth as a non-contact, analytical probe to characterize the intermolecular interactions of biologically active molecules, specifically as a way to understand, better develop, and use active pharmaceutical ingredients. An obstacle towards fully utilizing this technique as a probe is the need to couple features in the THz regions to specific vibrational modes and interactions. One solution is to use density functional theory (DFT) methods to assign specific vibrational modes to signals in the THz region, coupling atomistic insights to spectral features. Here, we use open source planewave DFT packages that employ ultrasoft pseudopotentials to assess the infrared (IR) response of organic compounds and complex co-crystal formulations in the solid state, with and without dispersion corrections. We compare our DFT computed lattice parameters and vibrational modes to experiment and comment on how to improve the agreement between theory and modeling to allow for THz spectroscopy to be used as an analytical probe in complex biologically relevant systems.
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Affiliation(s)
- Joseph W Bennett
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
| | | | - Shalisa M Oburn
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
| | | | - Mark A Arnold
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
| | - Sara E Mason
- Department of Chemistry, University of Iowa, Iowa City, IA 52242, USA.
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12
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Dampf SJ, Korter TM. Anomalous Temperature Dependence of the Lowest-Frequency Lattice Vibration in Crystalline γ-Aminobutyric Acid. J Phys Chem A 2019; 123:2058-2064. [DOI: 10.1021/acs.jpca.8b12572] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sara J. Dampf
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York 13244-4100, United States
| | - Timothy M. Korter
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York 13244-4100, United States
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13
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Yardimci NT, Jarrahi M. Nanostructure-Enhanced Photoconductive Terahertz Emission and Detection. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1802437. [PMID: 30156383 DOI: 10.1002/smll.201802437] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 07/29/2018] [Indexed: 06/08/2023]
Abstract
Photoconductive antennas are commonly used for terahertz wave generation and detection. However, their relatively low radiation power and detection sensitivity often place limitations on the signal-to-noise ratio and operation bandwidth of terahertz imaging and spectroscopy systems. Several different techniques are attempted to address these limitations. The most promising ones take advantage of the unique tools provided by nanotechnology. In this review, the recent nanotechnology-enabled advances in photoconductive antennas, which use nanostructures, such as optical nanoantennas, plasmonic structures, and optical nanocavities, to increase the interaction of the optical pump beam with the photoconductive semiconductor, are discussed. All of these techniques are experimentally demonstrated to be efficient tools for enhancing the performance of photoconductive antennas for terahertz wave generation and detection.
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Affiliation(s)
- Nezih Tolga Yardimci
- Electrical and Computer Engineering Department, University of California - Los Angeles, Los Angeles, CA, 90046, USA
| | - Mona Jarrahi
- Electrical and Computer Engineering Department, University of California - Los Angeles, Los Angeles, CA, 90046, USA
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14
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Lepodise LM, Horvat J, Lewis RA. Superficial and Fundamental Correspondences in the Terahertz/IR (6-15 THz) Absorption Spectra of Aspirin and Benzoic Acid. J Phys Chem A 2018; 122:6886-6893. [PMID: 30060668 DOI: 10.1021/acs.jpca.8b05393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The terahertz absorption spectra of aspirin and benzoic acid have been measured in the range 200-500 cm-1 (6-15 THz). Density-functional theory (DFT) modeling has assigned fundamental vibrational modes to the observed absorption bands. Hydrogen bonds between the crystalline planes of aspirin resulted in better agreement between the experimental and modeled spectra than for benzoic acid. The similar structure of these two molecules suggests a similar absorption spectrum, which indeed was obtained experimentally. However, the detailed crystal structure and molecular differences result in some of the apparently common absorption bands being assigned to different vibrational modes through the DFT modeling. Thus, our study importantly reveals that even though crystalline forms of two similar molecules may have similar experimental terahertz spectra, the resemblance may be superficial rather than fundamental.
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Affiliation(s)
- L M Lepodise
- Botswana International University of Science and Technology , Palapye , Botswana.,School of Physics and Institute for Superconducting and Electronic Materials , University of Wollongong , Wollongong , NSW 2522 , Australia
| | - J Horvat
- School of Physics and Institute for Superconducting and Electronic Materials , University of Wollongong , Wollongong , NSW 2522 , Australia
| | - R A Lewis
- School of Physics and Institute for Superconducting and Electronic Materials , University of Wollongong , Wollongong , NSW 2522 , Australia
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15
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Mizuno M, Yaekashiwa N, Watanabe S. Analysis of dermal composite conditions using collagen absorption characteristics in the THz range. BIOMEDICAL OPTICS EXPRESS 2018; 9:2277-2283. [PMID: 29760986 PMCID: PMC5946787 DOI: 10.1364/boe.9.002277] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 03/20/2018] [Accepted: 03/24/2018] [Indexed: 05/05/2023]
Abstract
The absorption characteristics of the dermis were reviewed in the terahertz range from 0.2 to 2 THz. The absorption magnitude of the dermis was higher than that of the epidermis model owing to the inclusion of collagen fibers. The heat denaturation of the collagen and the decrease of water content in the dermis caused a decrease in the absorption magnitude of the dermis. We verified that the absorption magnitude of collagen sheets at 1 THz similarly decreased by nearly 43% upon the heat treatment at approximately 70° C. When the heat-treated sheet was used as a scaffold for cell culture, the average growth rate of the fibroblast increased. These findings suggest that variation in the ability of cell growth in the dermis can be predicted using the absorption of the collagen or the difference between the absorptions of dermis and water.
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Affiliation(s)
- Maya Mizuno
- National Institute of Information and Communications Technology, Koganei, Tokyo 184-8795, Japan
| | | | - Soichi Watanabe
- National Institute of Information and Communications Technology, Koganei, Tokyo 184-8795, Japan
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16
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Truong BCQ, Fitzgerald AJ, Fan S, Wallace VP. Concentration analysis of breast tissue phantoms with terahertz spectroscopy. BIOMEDICAL OPTICS EXPRESS 2018; 9:1334-1349. [PMID: 29541525 PMCID: PMC5846535 DOI: 10.1364/boe.9.001334] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 02/14/2018] [Accepted: 02/14/2018] [Indexed: 05/30/2023]
Abstract
Terahertz imaging has been previously shown to be capable of distinguishing normal breast tissue from its cancerous form, indicating its applicability to breast conserving surgery. The heterogeneous composition of breast tissue is among the main challenges to progressing this potential research towards a practical application. In this paper, two concentration analysis methods are proposed for analyzing phantoms mimicking breast tissue. The dielectric properties and the double Debye parameters were used to determine the phantom composition. The first method is wholly based on the conventional effective medium theory while the second one combines this theoretical model with empirical polynomial models. Through assessing the accuracy of these methods, their potential for application to quantifying breast tissue pathology was confirmed.
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17
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Song M, Yang F, Liu L, Su C. Research on differences between 2-(2'-pyridyl)benzimidazole and 2-(4'-pyridyl)benzimidazole based on terahertz time-domain spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 191:125-133. [PMID: 29028504 DOI: 10.1016/j.saa.2017.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/09/2017] [Accepted: 10/01/2017] [Indexed: 06/07/2023]
Abstract
Due to the important pharmaceutical activities of benzimidazole derivatives, the differences between 2-(2'-pyridyl)benzimidazole and 2-(4'-pyridyl)benzimidazole were researched by terahertz time-domain spectroscopy and density functional theory systematically. Although the only difference between their molecular configurations is the different arrangement of nitrogen on pyridine ring, 2PBI and 4PBI have large differences in their experimental absorption spectra in the range of 0.2-2.5THz, such as the amount, amplitude and frequency position of absorption peaks. The validity of these results was confirmed by the theoretical results simulated using density functional theory. The possible reasons of these differences originate from the different dihedral angles between benzimidazole ring and pyridine ring and the different hydrogen-bonding interactions within crystal cell.
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Affiliation(s)
- Maojiang Song
- Guizhou Metrology Institute, Guiyang, Guizhou 550003, China.
| | - Fei Yang
- Guizhou Metrology Institute, Guiyang, Guizhou 550003, China
| | - Liping Liu
- Guizhou Metrology Institute, Guiyang, Guizhou 550003, China
| | - Caixia Su
- School of Big Data and Computer Science, Guizhou Normal University, Guizhou 550001, China.
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18
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Hitzer P, Bäuerle T, Drieschner T, Ostertag E, Paulsen K, van Lishaut H, Lorenz G, Rebner K. Process analytical techniques for hot-melt extrusion and their application to amorphous solid dispersions. Anal Bioanal Chem 2017; 409:4321-4333. [PMID: 28343348 DOI: 10.1007/s00216-017-0292-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 02/09/2017] [Accepted: 03/02/2017] [Indexed: 11/28/2022]
Abstract
Newly developed active pharmaceutical ingredients (APIs) are often poorly soluble in water. As a result the bioavailability of the API in the human body is reduced. One approach to overcome this restriction is the formulation of amorphous solid dispersions (ASDs), e.g., by hot-melt extrusion (HME). Thus, the poorly soluble crystalline form of the API is transferred into a more soluble amorphous form. To reach this aim in HME, the APIs are embedded in a polymer matrix. The resulting amorphous solid dispersions may contain small amounts of residual crystallinity and have the tendency to recrystallize. For the controlled release of the API in the final drug product the amount of crystallinity has to be known. This review assesses the available analytical methods that have been recently used for the characterization of ASDs and the quantification of crystalline API content. Well-established techniques like near- and mid-infrared spectroscopy (NIR and MIR, respectively), Raman spectroscopy, and emerging ones like UV/VIS, terahertz, and ultrasonic spectroscopy are considered in detail. Furthermore, their advantages and limitations are discussed with regard to general practical applicability as process analytical technology (PAT) tools in industrial manufacturing. The review focuses on spectroscopic methods which have been proven as most suitable for in-line and on-line process analytics. Further aspects are spectroscopic techniques that have been or could be integrated into an extruder.
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Affiliation(s)
- Patrick Hitzer
- Process Analysis and Technology (PA&T), Faculty Applied Chemistry, Reutlingen University, Alteburgstr. 150, 72762, Reutlingen, Germany
| | - Tim Bäuerle
- Process Analysis and Technology (PA&T), Faculty Applied Chemistry, Reutlingen University, Alteburgstr. 150, 72762, Reutlingen, Germany
| | - Tobias Drieschner
- Process Analysis and Technology (PA&T), Faculty Applied Chemistry, Reutlingen University, Alteburgstr. 150, 72762, Reutlingen, Germany
| | - Edwin Ostertag
- Process Analysis and Technology (PA&T), Faculty Applied Chemistry, Reutlingen University, Alteburgstr. 150, 72762, Reutlingen, Germany
| | - Katharina Paulsen
- AbbVie Deutschland GmbH & Co.KG, Knollstr. 50, 67061, Ludwigshafen, Germany
| | - Holger van Lishaut
- AbbVie Deutschland GmbH & Co.KG, Knollstr. 50, 67061, Ludwigshafen, Germany
| | - Günter Lorenz
- Process Analysis and Technology (PA&T), Faculty Applied Chemistry, Reutlingen University, Alteburgstr. 150, 72762, Reutlingen, Germany
| | - Karsten Rebner
- Process Analysis and Technology (PA&T), Faculty Applied Chemistry, Reutlingen University, Alteburgstr. 150, 72762, Reutlingen, Germany.
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Truong BCQ, Tuan HD, Fitzgerald AJ, Wallace VP, Nguyen HT. High correlation of double Debye model parameters in skin cancer detection. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2014:718-21. [PMID: 25570059 DOI: 10.1109/embc.2014.6943691] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The double Debye model can be used to capture the dielectric response of human skin in terahertz regime due to high water content in the tissue. The increased water proportion is widely considered as a biomarker of carcinogenesis, which gives rise of using this model in skin cancer detection. Therefore, the goal of this paper is to provide a specific analysis of the double Debye parameters in terms of non-melanoma skin cancer classification. Pearson correlation is applied to investigate the sensitivity of these parameters and their combinations to the variation in tumor percentage of skin samples. The most sensitive parameters are then assessed by using the receiver operating characteristic (ROC) plot to confirm their potential of classifying tumor from normal skin. Our positive outcomes support further steps to clinical application of terahertz imaging in skin cancer delineation.
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Liu J, Li P, Chen Y, Song X, Mao Q, Wu Y, Qi F, Zheng B, He J, Yang H, Wen Q, Zhang W. Flexible terahertz modulator based on coplanar-gate graphene field-effect transistor structure. OPTICS LETTERS 2016; 41:816-819. [PMID: 26872196 DOI: 10.1364/ol.41.000816] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The terahertz (THz) modulators, as an essential component of the THz system, have been developed by many efforts until now. However, the development of flexible THz modulators is hindered due to the lack of flexible THz modulating materials. Herein, for the first time to the best of our knowledge, we demonstrated the feasibility of flexible THz modulators based on the coplanar-gate field-effect transistor (FET) structure of ion-gel/graphene/polyethylene terephthalate. The THz transmittance through this THz graphene modulator can be well controlled with a modulation depth up to 22% by tuning the carrier concentration of graphene via electrical gating. Furthermore, because of the integration of high flexibilities of graphene, ion-gel, and polyethylene terephthalate (PET), the proposed THz graphene modulator shows superior flexible performance, where the modulation properties can be maintained almost unchanged, not only under bending deformations, but also before and after bending 1000 times. In addition, due to the unique structure of ion-gel/graphene/PET, the flexible THz graphene modulator has a low insertion loss (1.2 dB). Therefore, this Letter is expected to be beneficial for the potential applications, ranging from the traditional compact THz system to a new flexible THz technology.
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Truong BCQ, Tuan HD, Fitzgerald AJ, Wallace VP, Nguyen HT. Breast Cancer classification using extracted parameters from a terahertz dielectric model of human breast tissue. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2016; 2015:2804-7. [PMID: 26736874 DOI: 10.1109/embc.2015.7318974] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Our previous study proposed a dielectric model for human breast tissue and provided initial analysis of classification potential of the eight model parameters and their multiparameter combinations with the support vector machine (SVM). A combination of three model parameters could achieve a leave-one-out cross validation accuracy of 93.2%. However, the SVM approach fails to exploit the combinations of more than three model parameters for classification improvement. Thus, the Bayesian neural network (BNN) method is employed to overcome this problem based on its advantages of handling our small data and high complexity of the multiparamter combinations. The BNN successfully classifies the data using the combinations of four model parameters with an accuracy, estimated by leave-one-out cross validation, of 97.3%. Overall performance assessed by leaveone-out and repeated random-subsampling cross validations for all examined combinations is also remarkably improved by BNN. The results indicate the advance of BNN as compared to SVM in utilising the model parameters for detecting tumour from normal breast tissue.
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22
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Dohi M, Momose W, Yoshino H, Hara Y, Yamashita K, Hakomori T, Sato S, Terada K. Application of terahertz pulse imaging as PAT tool for non-destructive evaluation of film-coated tablets under different manufacturing conditions. J Pharm Biomed Anal 2015; 119:104-13. [PMID: 26678177 DOI: 10.1016/j.jpba.2015.11.046] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/26/2015] [Accepted: 11/27/2015] [Indexed: 10/22/2022]
Abstract
Film-coated tablets (FCTs) are a popular solid dosage form in pharmaceutical industry. Manufacturing conditions during the film-coating process affect the properties of the film layer, which might result in critical quality problems. Here, we analyzed the properties of the film layer using a non-destructive approach with terahertz pulsed imaging (TPI). Hydrophilic tablets that become distended upon water absorption were used as core tablets and coated with film under different manufacturing conditions. TPI-derived parameters such as film thickness (FT), film surface reflectance (FSR), and interface density difference (IDD) between the film layer and core tablet were affected by manufacturing conditions and influenced critical quality attributes of FCTs. Relative standard deviation of FSR within tablets correlated well with surface roughness. Tensile strength could be predicted in a non-destructive manner using the multivariate regression equation to estimate the core tablet density by film layer density and IDD. The absolute value of IDD (Lateral) correlated with the risk of cracking on the lateral film layer when stored in a high-humidity environment. Further, in-process control was proposed for this value during the film-coating process, which will enable a feedback control system to be applied to process parameters and reduced risk of cracking without a stability test.
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Affiliation(s)
- Masafumi Dohi
- Pharmaceutical Research & Technology Laboratories, Astellas Pharma Inc., Ozumi 180, Yaizu, Shizuoka 425-0072, Japan; Faculty of Pharmaceutical Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan; PAT Committee, Japan Society of Pharmaceutical Machinery and Engineering, Miyoshi Bldg. 3F, 2-7-3 Kandata-cho, Chiyoda-ku, Tokyo 101-0046, Japan.
| | - Wataru Momose
- Pharmaceutical Research & Technology Laboratories, Astellas Pharma Inc., Ozumi 180, Yaizu, Shizuoka 425-0072, Japan
| | - Hiroyuki Yoshino
- Pharmaceutical Research & Technology Laboratories, Astellas Pharma Inc., Ozumi 180, Yaizu, Shizuoka 425-0072, Japan
| | - Yuko Hara
- Pharmaceutical Research & Technology Laboratories, Astellas Pharma Inc., Ozumi 180, Yaizu, Shizuoka 425-0072, Japan
| | - Kazunari Yamashita
- Pharmaceutical Research & Technology Laboratories, Astellas Pharma Inc., Ozumi 180, Yaizu, Shizuoka 425-0072, Japan
| | - Tadashi Hakomori
- Pharmaceutical Research & Technology Laboratories, Astellas Pharma Inc., Ozumi 180, Yaizu, Shizuoka 425-0072, Japan
| | - Shusaku Sato
- Advantest Corporation, 48-2 Matsubara, Kamiayashi, Aoba-ku, Sendai, Miyagi 989-3124, Japan
| | - Katsuhide Terada
- Faculty of Pharmaceutical Science, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan; PAT Committee, Japan Society of Pharmaceutical Machinery and Engineering, Miyoshi Bldg. 3F, 2-7-3 Kandata-cho, Chiyoda-ku, Tokyo 101-0046, Japan
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23
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Sleiman JB, Bousquet B, Palka N, Mounaix P. Quantitative Analysis of Hexahydro-1,3,5-trinitro-1,3,5, Triazine/Pentaerythritol Tetranitrate (RDX-PETN) Mixtures by Terahertz Time Domain Spectroscopy. APPLIED SPECTROSCOPY 2015; 69:1464-1471. [PMID: 26556760 DOI: 10.1366/15-07937] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Absorption spectra of explosives such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), pentaerythritol tetranitrate (PETN), and mixtures of both were measured by terahertz time domain spectroscopy (THz-TDS). Chemometrics was applied to quantitative analysis of terahertz absorbance spectra obtained in transmission mode to predict the relative amounts of RDX and PETN in samples containing pure components or their mixtures. This analysis was challenging because significant spectral overlap prevented identification of each product fingerprint. Partial least squares (PLS) regression models were thus applied to the terahertz spectra. A comparison between the so-called PLS1 and PLS2 algorithms was performed to predict the PETN concentrations in mixture samples. PLS2 demonstrated better predictive ability than PLS1 with RMSE value lower than 3.5 mg for 400 mg total weight pellets. Moreover, the influence of the highly overlapping spectral frequency band was investigated by reducing the original 0.2-3 THz (6-100 cm(-1)) spectral band to 1.8-3 THz (60-100 cm(-1)). The predictive ability was quite similar in both cases, highlighting the excellent ability of chemometrics to perform quantitative analysis when applied to THz-TDS data, even in the case of highly overlapping spectra.
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24
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Wallace VP, Ferachou D, Ke P, Day K, Uddin S, Casas-Finet J, Van Der Walle CF, Falconer RJ, Zeitler JA. Modulation of the Hydration Water Around Monoclonal Antibodies on Addition of Excipients Detected by Terahertz Time-Domain Spectroscopy. J Pharm Sci 2015; 104:4025-4033. [DOI: 10.1002/jps.24630] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 07/25/2015] [Accepted: 08/04/2015] [Indexed: 12/25/2022]
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25
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Agrawal AM, Pandey P. Scale Up of Pan Coating Process Using Quality by Design Principles. J Pharm Sci 2015. [DOI: 10.1002/jps.24582] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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26
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Deshmukh P, Mendez-Aller M, Singh A, Pal S, Prabhu SS, Nanal V, Pillay RG, Döhler GH, Preu S. Continuous wave terahertz radiation from antennas fabricated on C¹²-irradiated semi-insulating GaAs. OPTICS LETTERS 2015; 40:4540-4543. [PMID: 26421576 DOI: 10.1364/ol.40.004540] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We demonstrate continuous wave (CW) terahertz generation from antennas fabricated on C12-irradiated semi-insulating (SI) GaAs substrates. The dark current drawn by the antennas fabricated on irradiated substrates is ∼3 to 4 orders of magnitude lower compared to antennas fabricated on un-irradiated substrates, while the photocurrents decrease by only ∼1.5 orders of magnitude. This can be attributed to the strong reduction of the carrier lifetime that is 2.5 orders of magnitude, with values around τ(rec)=0.2 ps. Reduced thermal heating allows for higher bias voltages to the irradiated antenna devices resulting in higher CW terahertz power, just slightly lower than that of low-temperature grown GaAs (LT GaAs)at similar excitation conditions.
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27
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Truong BCQ, Tuan HD, Fitzgerald AJ, Wallace VP, Nguyen HT. A dielectric model of human breast tissue in terahertz regime. IEEE Trans Biomed Eng 2014; 62:699-707. [PMID: 25347869 DOI: 10.1109/tbme.2014.2364025] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The double Debye model has been used to understand the dielectric response of different types of biological tissues at terahertz (THz) frequencies but fails in accurately simulating human breast tissue. This leads to limited knowledge about the structure, dynamics, and macroscopic behavior of breast tissue, and hence, constrains the potential of THz imaging in breast cancer detection. The first goal of this paper is to propose a new dielectric model capable of mimicking the spectra of human breast tissue's complex permittivity in THz regime. Namely, a non-Debye relaxation model is combined with a single Debye model to produce a mixture model of human breast tissue. A sampling gradient algorithm of nonsmooth optimization is applied to locate the optimal fitting solution. Samples of healthy breast tissue and breast tumor are used in the simulation to evaluate the effectiveness of the proposed model. Our simulation demonstrates exceptional fitting quality in all cases. The second goal is to confirm the potential of using the parameters of the proposed dielectric model to distinguish breast tumor from healthy breast tissue, especially fibrous tissue. Statistical measures are employed to analyze the discrimination capability of the model parameters while support vector machines are applied to assess the possibility of using the combinations of these parameters for higher classification accuracy. The obtained analysis confirms the classification potential of these features.
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28
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Use of finite difference time domain simulations and Debye theory for modelling the terahertz reflection response of normal and tumour breast tissue. PLoS One 2014; 9:e99291. [PMID: 25010734 PMCID: PMC4091867 DOI: 10.1371/journal.pone.0099291] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 05/13/2014] [Indexed: 11/19/2022] Open
Abstract
The aim of this work was to evaluate the capabilities of Debye theory combined with Finite Difference Time Domain (FDTD) methods to simulate the terahertz (THz) response of breast tissues. Being able to accurately model breast tissues in the THz regime would facilitate the understanding of image contrast parameters used in THz imaging of breast cancer. As a test case, the model was first validated using liquid water and simulated reflection pulses were compared to experimental measured pulses with very good agreement (p = 1.00). The responses of normal and cancerous breast tissues were simulated with Debye properties and the correlation with measured data was still high for tumour (p = 0.98) and less so for normal breast (p = 0.82). Sections of the time domain pulses showed clear differences that were also evident in the comparison of pulse parameter values. These deviations may arise from the presence of adipose and other inhomogeneities in the breast tissue that are not accounted for when using the Debye model. In conclusion, the study demonstrates the power of the model for simulating THz reflection imaging; however, for biological tissues extra Debye terms or a more detailed theory may be required to link THz image contrast to physiological composition and structural changes of breast tissue associated with differences between normal and tumour tissues.
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29
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Lui HS, Taimre T, Bertling K, Lim YL, Dean P, Khanna SP, Lachab M, Valavanis A, Indjin D, Linfield EH, Davies AG, Rakić AD. Terahertz inverse synthetic aperture radar imaging using self-mixing interferometry with a quantum cascade laser. OPTICS LETTERS 2014; 39:2629-2632. [PMID: 24784063 DOI: 10.1364/ol.39.002629] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We propose a terahertz (THz)-frequency synthetic aperture radar imaging technique based on self-mixing (SM) interferometry, using a quantum cascade laser. A signal processing method is employed which extracts and exploits the radar-related information contained in the SM signals, enabling the creation of THz images with improved spatial resolution. We demonstrate this by imaging a standard resolution test target, achieving resolution beyond the diffraction limit.
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30
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Terahertz pulsed imaging as an advanced characterisation tool for film coatings--a review. Int J Pharm 2013; 457:510-20. [PMID: 23570960 DOI: 10.1016/j.ijpharm.2013.03.053] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 03/28/2013] [Accepted: 03/28/2013] [Indexed: 11/23/2022]
Abstract
Solid dosage forms are the pharmaceutical drug delivery systems of choice for oral drug delivery. These solid dosage forms are often coated to modify the physico-chemical properties of the active pharmaceutical ingredients (APIs), in particular to alter release kinetics. Since the product performance of coated dosage forms is a function of their critical coating attributes, including coating thickness, uniformity, and density, more advanced quality control techniques than weight gain are required. A recently introduced non-destructive method to quantitatively characterise coating quality is terahertz pulsed imaging (TPI). The ability of terahertz radiation to penetrate many pharmaceutical materials enables structural features of coated solid dosage forms to be probed at depth, which is not readily achievable with other established imaging techniques, e.g. near-infrared (NIR) and Raman spectroscopy. In this review TPI is introduced and various applications of the technique in pharmaceutical coating analysis are discussed. These include evaluation of coating thickness, uniformity, surface morphology, density, defects and buried structures as well as correlation between TPI measurements and drug release performance, coating process monitoring and scale up. Furthermore, challenges and limitations of the technique are discussed.
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31
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Bergues-Pupo AE, Bergues JM, Falo F. Modeling the interaction of DNA with alternating fields. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:022703. [PMID: 23496544 DOI: 10.1103/physreve.87.022703] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Indexed: 05/22/2023]
Abstract
We study the influence of a terahertz field on thermal properties of DNA molecules. A Peyrard-Bishop-Dauxois model with the inclusion of a solvent interaction term is considered. The terahertz field is included as a sinusoidal driven force in the equation of motion. We show how under certain field and system parameters, the melting transition and bubble formation are modified.
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Affiliation(s)
- A E Bergues-Pupo
- Departamento de Física, Universidad de Oriente, 90500 Santiago de Cuba, Cuba
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32
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Truong BCQ, Tuan HD, Kha HH, Nguyen HT. Debye parameter extraction for characterizing interaction of terahertz radiation with human skin tissue. IEEE Trans Biomed Eng 2013; 60:1528-37. [PMID: 23314766 DOI: 10.1109/tbme.2013.2237908] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This paper is concerned with parameter extraction for the double Debye model, which is used for analytically determining human skin permittivity. These parameters are thought to be the origin of contrast in terahertz (THz) images of skin cancer. The existing extraction methods could generate Debye models, which track their measurements accurately at frequencies higher than 1 THz but poorly at lower frequencies, where the majority of permittivity contrast between healthy and diseased skin tissues is actually observed. We propose a global optimization-based parameter extraction, which results in globally accurate tracking and thus supports the full validity of the Debye model for simulating human skin permittivity in the whole usable THz frequencies. Numerical results confirm viability of our novel methodology.
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Affiliation(s)
- Bao C Q Truong
- Centre for Health Technologies, Faculty of Engineering and Information Technology, University of Technology Sydney, Sydney 2007, Australia.
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33
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Yu C, Fan S, Sun Y, Pickwell-Macpherson E. The potential of terahertz imaging for cancer diagnosis: A review of investigations to date. Quant Imaging Med Surg 2012; 2:33-45. [PMID: 23256057 DOI: 10.3978/j.issn.2223-4292.2012.01.04] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2012] [Accepted: 01/17/2012] [Indexed: 11/14/2022]
Abstract
The terahertz region lies between the microwave and infrared regions of the electromagnetic spectrum such that it is strongly attenuated by water and very sensitive to water content. Terahertz radiation has very low photon energy and thus it does not pose any ionization hazard for biological tissues. Because of these characteristic properties, there has been an increasing interest in terahertz imaging and spectroscopy for biological applications within the last few years and more and more terahertz spectra are being reported, including spectroscopic studies of cancer. The presence of cancer often causes increased blood supply to affected tissues and a local increase in tissue water content may be observed: this acts as a natural contrast mechanism for terahertz imaging of cancer. Furthermore the structural changes that occur in affected tissues have also been shown to contribute to terahertz image contrast. This paper introduces terahertz technology and provides a short review of recent advances in terahertz imaging and spectroscopy techniques. In particular investigations relating to the potential of terahertz imaging and spectroscopy for cancer diagnosis will be highlighted.
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Affiliation(s)
- Calvin Yu
- Department of Electronic & Computer Engineering, Hong Kong University of Science and Technology, Hong Kong
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34
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Zheng ZP, Fan WH. First principles investigation of L-alanine in terahertz region. J Biol Phys 2012; 38:405-13. [PMID: 23729906 DOI: 10.1007/s10867-012-9261-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Accepted: 01/03/2012] [Indexed: 10/14/2022] Open
Abstract
Terahertz absorption spectrum (0.5-4.0 THz) of L-alanine in the solid phase was measured by terahertz time-domain spectroscopy at room temperature. Simulations utilizing gaseous-state and solid-state theory were performed to determine the origins of the observed vibrational features. Our calculations showed that the measured features in solid-state materials could be well understood by considering the crystal packing interactions in a solid-state density functional theory calculation. Furthermore, intermolecular vibrations of L-alanine are found to be the dominating contributions to these measured spectral features in the range of 0.5-4.0 THz, except that located at 3.11 THz.
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Affiliation(s)
- Zhuan-Ping Zheng
- State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an, 710119 China
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Truong BCQ, Tuan HD, Kha HH, Nguyen HT. Global optimization for human skin investigation in terahertz. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2012; 2012:5474-5477. [PMID: 23367168 DOI: 10.1109/embc.2012.6347233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this paper, the electromagnetic interaction between human skin and terahertz radiation is investigated through the double Debye parameters' extraction algorithm. The changes of skin content are contrasted at the frequencies below one terahertz(THz) but the recent approaches could provide only a rough estimation. We propose an global optimization based identification, which results in globally accurate estimators in the frequency range up to two THz, and thus supports the validity of Debye model for Terahertz wave's propagation and reflection in skin. Simulation results confirm our prominent methodology.
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Affiliation(s)
- Bao C Q Truong
- Centre for Health Technology, Faculty of Engineering and Information Technology, University of Technology, Sydney, Australia.
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Fitzgerald AJ, Pinder S, Purushotham AD, O'Kelly P, Ashworth PC, Wallace VP. Classification of terahertz-pulsed imaging data from excised breast tissue. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:016005. [PMID: 22352655 DOI: 10.1117/1.jbo.17.1.016005] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We investigate the efficacy of using data reduction techniques to aid classification of terahertz (THz) pulse data obtained from tumor and normal breast tissue. Fifty-one samples were studied from patients undergoing breast surgery at Addenbrooke's Hospital in Cambridge and Guy's Hospital in London. Three methods of data reduction were used: ten heuristic parameters, principal components of the pulses, and principal components of the ten parameter space. Classification was performed using the support vector machine approach with a radial basis function. The best classification accuracy, when using all ten components, came from using the principal components on the pulses and principal components on the parameter, with an accuracy of 92%. When less than ten components were used, the principal components on the parameter space outperformed the other methods. As a visual demonstration of the classification technique, we apply the data reduction/classification to several example images and demonstrate that, aside from some interpatient variability and edge effects, the algorithm gives good classification on terahertz data from breast tissue. The results indicate that under controlled conditions data reduction and SVM classification can be used with good accuracy to classify tumor and normal breast tissue.
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38
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King MD, Korter TM. Noncovalent interactions between modified cytosine and guanine DNA base pair mimics investigated by terahertz spectroscopy and solid-state density functional theory. J Phys Chem A 2011; 115:14391-6. [PMID: 22107026 DOI: 10.1021/jp208883t] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Modified cytosine and guanine nucleobases cocrystallize in a hydrogen bonding configuration similar to that observed in native DNA. The noncovalent interactions binding these base pairs in the crystalline solid were investigated using terahertz (THz) spectroscopy and solid-state density functional theory (DFT). While stronger hydrogen bonding interactions are responsible for the general molecular orientations in the crystalline state, it is the weaker dipole-dipole and dispersion forces that determine the overall packing arrangement. The inclusion of dispersion interactions in the DFT calculations was found to be necessary to accurately simulate the unit cell structure and THz vibrational spectrum. Using properly modeled intermolecular potentials, the lattice vibrational motions of the cytosine and guanine derivatives were calculated. The vibrational characters of the modes exhibited by the DNA base pair mimic in the THz region were primarily rotational motions and are indicative of the energies and the nature of vibrations that would likely be observed between similar base pairs in DNA molecules.
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Affiliation(s)
- Matthew D King
- Department of Chemistry, Syracuse University, Syracuse, New York 13244-4100, United States
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39
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Shen YC. Terahertz pulsed spectroscopy and imaging for pharmaceutical applications: A review. Int J Pharm 2011; 417:48-60. [DOI: 10.1016/j.ijpharm.2011.01.012] [Citation(s) in RCA: 162] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 12/30/2010] [Accepted: 01/06/2011] [Indexed: 10/18/2022]
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Miura Y, Kamataki A, Uzuki M, Sasaki T, Nishizawa JI, Sawai T. Terahertz-wave spectroscopy for precise histopathological imaging of tumor and non-tumor lesions in paraffin sections. TOHOKU J EXP MED 2011; 223:291-6. [PMID: 21467828 DOI: 10.1620/tjem.223.291] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Terahertz (THz; 10(12) Hz) waves have a frequency from 0.1 to 10 THz between the visible light and microwave domains. THz waves are expected to be useful for analysis of the histological features, without any staining procedure that is an indispensable prerequisite for optical microscopy. It has been demonstrated that THz transmittances at cancer and normal tissues are different. However, spectroscopy that is currently used is applicable for imaging only small areas at fixed-wavelength. In this study, we have developed a spectrometer employing a gallium phosphide (GaP) THz-generator and applied it to examine large areas of tissue specimens using a wide range of wavelengths. We thus examined the whole areas of two paraffin sections (metastatic liver cancer and acute myocardial infarction) in a frequency range of 1 to 6 THz, and compared the THz images of ordinary paraffin sections with the histological features detected by microscopy. THz imaging showed striking contrasts between cancerous and non-cancerous regions at 3.7 THz. Likewise, the precise imaging was achieved in the infarct myocardium at 3.6 THz. Images of THz transmittances in optimal wavelength were well matched with HE histological features both in cancer and myocardial tissues. Cancer regions showed higher transmittance than non-cancerous regions in liver. Old scar regions showed low transmittance, and necrotic regions showed relatively higher transmittance than normal myocardial areas. Thus, THz imaging precisely reflects tissue conditions such as tumor, non-tumor tissues, tissue degeneration and fibrosis. The newly established THz spectroscopy would be useful for pathological diagnosis of routinely processed specimens.
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Affiliation(s)
- Yasuhiro Miura
- Department of Pathology, Iwate Medical University School of Medicine, Morioka, Japan
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Reid CB, Fitzgerald A, Reese G, Goldin R, Tekkis P, O'Kelly PS, Pickwell-MacPherson E, Gibson AP, Wallace VP. Terahertz pulsed imaging of freshly excised human colonic tissues. Phys Med Biol 2011; 56:4333-53. [PMID: 21709342 DOI: 10.1088/0031-9155/56/14/008] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We present the results from a feasibility study which measures properties in the terahertz frequency range of excised cancerous, dysplastic and healthy colonic tissues from 30 patients. We compare their absorption and refractive index spectra to identify trends which may enable different tissue types to be distinguished. In addition, we present statistical models based on variations between up to 17 parameters calculated from the reflected time and frequency domain signals of all the measured tissues. These models produce a sensitivity of 82% and a specificity of 77% in distinguishing between healthy and all diseased tissues and a sensitivity of 89% and a specificity of 71% in distinguishing between dysplastic and healthy tissues. The contrast between the tissue types was supported by histological staining studies which showed an increased vascularity in regions of increased terahertz absorption.
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Affiliation(s)
- Caroline B Reid
- Department of Medical Physics and Bioengineering, University College London, London, UK.
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Ney M, Abdulhalim I. Modeling of reflectometric and ellipsometric spectra from the skin in the terahertz and submillimeter waves region. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:067006. [PMID: 21721827 DOI: 10.1117/1.3592779] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The human skin is modeled as a stack of homogeneous layers in the terahertz and submillimeter waves regions with some anisotropy due to the helical sweat glands and other elongated entities. A dielectric model for the skin is presented, valid for a wider frequency range (up to the terahertz region) taking into account the dispersive nature of the effective conductivity. Polarized reflectivity and generalized ellipsometric parameters are calculated versus angle and wavelength. Recent studies have claimed that the helical sweat ducts act as an array of low-Q helical antennae and are dominant in shaping the spectral response in the sub-terahertz region. We found that water absorption, dispersion and multiple interference effects play the major role in shaping the spectrum without the need for the assumption of the sweat ducts acting as low-Q helical antennae. High sensitivities to the water content are found particularly in the ellipsometric parameters at large incidence angles. Hence a new methodology is proposed to detect skin cancer using variable angle ellipsometry or polarized reflectometry. The parameter found with the highest sensitivity to water content is cos Δ(pp) with Δ(pp) being the phase of the on-diagonal reflection matrix ratio between p-to-p polarization.
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Affiliation(s)
- Michael Ney
- Ben Gurion University, Department of Electro-Optic Engineering and Ilse Katz Institute for Nanoscale Science and Technology, Beer Sheva 84105, Israel
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King MD, Buchanan WD, Korter TM. Identification and Quantification of Polymorphism in the Pharmaceutical Compound Diclofenac Acid by Terahertz Spectroscopy and Solid-State Density Functional Theory. Anal Chem 2011; 83:3786-92. [DOI: 10.1021/ac2001934] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Matthew D. King
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York 13244-4100, United States
| | - William D. Buchanan
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York 13244-4100, United States
| | - Timothy M. Korter
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York 13244-4100, United States
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Wilmink GJ, Ibey BL, Tongue T, Schulkin B, Laman N, Peralta XG, Roth CC, Cerna CZ, Rivest BD, Grundt JE, Roach WP. Development of a compact terahertz time-domain spectrometer for the measurement of the optical properties of biological tissues. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:047006. [PMID: 21529096 DOI: 10.1117/1.3570648] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Terahertz spectrometers and imaging systems are currently being evaluated as biomedical tools for skin burn assessment. These systems show promise, but due to their size and weight, they have restricted portability, and are impractical for military and battlefield settings where space is limited. In this study, we developed and tested the performance of a compact, light, and portable THz time-domain spectroscopy (THz-TDS) device. Optical properties were collected with this system from 0.1 to 1.6 THz for water, ethanol, and several ex vivo porcine tissues (muscle, adipose, skin). For all samples tested, we found that the index of refraction (n) decreases with frequency, while the absorption coefficient (μ(a)) increases with frequency. Muscle, adipose, and frozen/thawed skin samples exhibited comparable n values ranging between 2.5 and 2.0, whereas the n values for freshly harvested skin were roughly 40% lower. Additionally, we found that the freshly harvested samples exhibited higher μ(a) values than the frozen/thawed skin samples. Overall, for all liquids and tissues tested, we found that our system measured optical property values that were consistent with those reported in the literature. These results suggest that our compact THz spectrometer performed comparable to its larger counterparts, and therefore may be a useful and practical tool for skin health assessment.
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Affiliation(s)
- Gerald J Wilmink
- Air Force Research Laboratory, 711 Human Performance Wing, Human Effectiveness Directorate, Radio Frequency Radiation Branch, 8262 Hawks Road, Brooks City-Base, Texas 78235, USA.
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Sun Y, Sy MY, Wang YXJ, Ahuja AT, Zhang YT, Pickwell-MacPherson E. A promising diagnostic method: Terahertz pulsed imaging and spectroscopy. World J Radiol 2011; 3:55-65. [PMID: 21512652 PMCID: PMC3080051 DOI: 10.4329/wjr.v3.i3.55] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 01/19/2010] [Accepted: 01/26/2010] [Indexed: 02/06/2023] Open
Abstract
The terahertz band lies between the microwave and infrared regions of the electromagnetic spectrum. This radiation has very low photon energy and thus it does not pose any ionization hazard for biological tissues. It is strongly attenuated by water and very sensitive to water content. Unique absorption spectra due to intermolecular vibrations in this region have been found in different biological materials. These unique features make terahertz imaging very attractive for medical applications in order to provide complimentary information to existing imaging techniques. There has been an increasing interest in terahertz imaging and spectroscopy of biologically related applications within the last few years and more and more terahertz spectra are being reported. This paper introduces terahertz technology and provides a short review of recent advances in terahertz imaging and spectroscopy techniques, and a number of applications such as molecular spectroscopy, tissue characterization and skin imaging are discussed.
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King MD, Buchanan WD, Korter TM. Understanding the Terahertz Spectra of Crystalline Pharmaceuticals: Terahertz Spectroscopy and Solid-State Density Functional Theory Study of (S)-(+)-Ibuprofen and (RS)-Ibuprofen. J Pharm Sci 2011; 100:1116-29. [DOI: 10.1002/jps.22339] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 08/03/2010] [Accepted: 08/07/2010] [Indexed: 11/09/2022]
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Wilmink GJ, Rivest BD, Roth CC, Ibey BL, Payne JA, Cundin LX, Grundt JE, Peralta X, Mixon DG, Roach WP. In vitro investigation of the biological effects associated with human dermal fibroblasts exposed to 2.52 THz radiation. Lasers Surg Med 2010; 43:152-63. [PMID: 20740621 DOI: 10.1002/lsm.20960] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2010] [Indexed: 11/11/2022]
Abstract
BACKGROUND Terahertz (THz) radiation sources are increasingly being used in military, defense, and medical applications. However, the biological effects associated with this type of radiation are not well characterized. In this study, we evaluated the cellular and molecular response of human dermal fibroblasts exposed to THz radiation. METHODS In vitro exposures were performed in a temperature-controlled chamber using a molecular gas THz laser (2.52 THz, 84.8 mW cm(-2), durations: 5, 10, 20, 40, or 80 minutes). Both computational and empirical dosimetric techniques were conducted using finite-difference time-domain (FDTD) modeling approaches, infrared cameras, and thermocouples. Cellular viability was assessed using conventional MTT assays. In addition, the transcriptional activation of protein and DNA sensing genes were evaluated using qPCR. Comparable analyses were also conducted for hyperthermic and genotoxic positive controls. RESULTS We found that cellular temperatures increased by 3°C during all THz exposures. We also found that for each exposure duration tested, the THz and hyperthermic exposure groups exhibited equivalent levels of cell survival (≥90%) and heat shock protein expression (∼3.5-fold increases). In addition, the expression of DNA sensing and repair genes was unchanged in both groups; however, appreciable increases were observed in the genotoxic controls. CONCLUSIONS Human dermal fibroblasts exhibit comparable cellular and molecular effects when exposed to THz radiation and hyperthermic stress. These findings suggest that radiation at 2.52 THz generates primarily thermal effects in mammalian cells. Therefore, we conclude that THz-induced bioeffects may be accurately predicted with conventional thermal damage models.
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Affiliation(s)
- Gerald J Wilmink
- 711th Human Performance Wing, Radio Frequency Radiation Branch, Air Force Research Laboratory, Brooks City-Base, Texas, USA.
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Amigo JM. Practical issues of hyperspectral imaging analysis of solid dosage forms. Anal Bioanal Chem 2010; 398:93-109. [DOI: 10.1007/s00216-010-3828-z] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 05/02/2010] [Accepted: 05/04/2010] [Indexed: 11/29/2022]
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Zeitler JA, Taday PF, Newnham DA, Pepper M, Gordon KC, Rades T. Terahertz pulsed spectroscopy and imaging in the pharmaceutical setting - a review. J Pharm Pharmacol 2010; 59:209-23. [PMID: 17270075 DOI: 10.1211/jpp.59.2.0008] [Citation(s) in RCA: 157] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Abstract
Terahertz pulsed spectroscopy (TPS) and terahertz pulsed imaging (TPI) are two novel techniques for the physical characterization of pharmaceutical drug materials and final solid dosage forms, utilizing spectral information in the far infrared region of the electromagnetic spectrum. This review focuses on the development and performance of pharmaceutical applications of terahertz technology compared with other tools for physical characterization. TPS can be used to characterize crystalline properties of drugs and excipients. Different polymorphic forms of a drug can be readily distinguished and quantified. Recent developments towards a better understanding of the fundamental theory behind spectroscopy in the far infrared have been discussed. Applications for TPI include the measurement of coating thickness and uniformity in coated pharmaceutical tablets, structural imaging and 3D chemical imaging of solid dosage forms.
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Affiliation(s)
- J Axel Zeitler
- School of Pharmacy, University of Otago, P.O. Box 56, Dunedin, New Zealand
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King MD, Hakey PM, Korter TM. Discrimination of Chiral Solids: A Terahertz Spectroscopic Investigation of l- and dl-Serine. J Phys Chem A 2010; 114:2945-53. [DOI: 10.1021/jp911863v] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew D. King
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York, 13244-4100
| | - Patrick M. Hakey
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York, 13244-4100
| | - Timothy M. Korter
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, New York, 13244-4100
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