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He X, Xu J, Wang X, Ge C, Li S, Wang L, Xu Y. Enrichment and detection of VEGF 165 in blood samples on a microfluidic chip integrated with multifunctional units. LAB ON A CHIP 2023; 23:2469-2476. [PMID: 37092607 DOI: 10.1039/d3lc00225j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In this paper, a multifunctional microfluidic chip integrated with a centrifugal separation zone, aqueous two-phase system (ATPS) mixing zone and enrichment detection zone was proposed and fabricated. An automatic and efficient separation and quantitative analysis method for vascular endothelial growth factor 165 (VEGF165) in whole blood samples was established with the designed microfluidic chip. A blood sample was divided into blood cells and plasma in the centrifugation zone. In the ATPS mixing zone, plasma was mixed with PEG/KH2PO4 aqueous two-phase solution containing Apt-Au NP nanoprobes. In the enrichment detection zone, the mixture was separated on CN140 modified with a ZnO NP-anti VEGF165 nanostructure. The VEGF165 captured by Apt-Au NPs was distributed in the PEG phase, concentrated at the front of CN140 and combined with anti-VEGF165 to form a sandwich structure. The sensitive detection of VEGF165 was achieved through fluorescence resonance energy transfer between rhodamine B and Au NPs on the nanoprobe. Under the optimized rotation program, capillary and centrifugal forces propelled the fluid in the whole process of pretreatment and detection. The detection linear range was between 1 pg mL-1 and 50 ng mL-1, the detection limit of VEGF165 in blood was 0.22 pg mL-1 and the enrichment efficiency was 983. It was illustrated that a convenient and reliable way for detection of tumor markers based on the multifunctional microfluidic chip was provided and it has a potential value for early screening and prognosis of clinical cancer.
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Affiliation(s)
- Xinyu He
- Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Chongqing University, Shapingba, Chongqing, 400044 PR China.
- School of Chemistry and Chemical Engineering, Chongqing University, Shapingba, Chongqing, 400044 PR China
- International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Shapingba, Chongqing, 400044 PR China
| | - Junyan Xu
- Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Chongqing University, Shapingba, Chongqing, 400044 PR China.
- School of Chemistry and Chemical Engineering, Chongqing University, Shapingba, Chongqing, 400044 PR China
- International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Shapingba, Chongqing, 400044 PR China
| | - Xiaoli Wang
- Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Chongqing University, Shapingba, Chongqing, 400044 PR China.
- School of Optoelectronic Engineering, Chongqing University, Shapingba, Chongqing, 400044 PR China
- International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Shapingba, Chongqing, 400044 PR China
| | - Chuang Ge
- Key Laboratory of Translational Research for Cancer Metastasis and Individualized Treatment, Chongqing University Cancer Hospital, Chongqing, 400030 PR China
| | - Shunbo Li
- Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Chongqing University, Shapingba, Chongqing, 400044 PR China.
- School of Optoelectronic Engineering, Chongqing University, Shapingba, Chongqing, 400044 PR China
- International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Shapingba, Chongqing, 400044 PR China
| | - Li Wang
- Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Chongqing University, Shapingba, Chongqing, 400044 PR China.
- School of Optoelectronic Engineering, Chongqing University, Shapingba, Chongqing, 400044 PR China
- International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Shapingba, Chongqing, 400044 PR China
| | - Yi Xu
- Key Disciplines Lab of Novel Micro-Nano Devices and System Technology, Key Laboratory of Optoelectronic Technology and Systems, Ministry of Education, Chongqing University, Shapingba, Chongqing, 400044 PR China.
- School of Optoelectronic Engineering, Chongqing University, Shapingba, Chongqing, 400044 PR China
- International R & D center of Micro-nano Systems and New Materials Technology, Chongqing University, Shapingba, Chongqing, 400044 PR China
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Mao X, Wang Y, Jiang L, Zhang H, Zhao Y, Liu P, Liu J, Hammock BD, Zhang C. A Polydopamine-Coated Gold Nanoparticles Quenching Quantum Dots-Based Dual-Readout Lateral Flow Immunoassay for Sensitive Detection of Carbendazim in Agriproducts. BIOSENSORS 2022; 12:bios12020083. [PMID: 35200343 PMCID: PMC8869244 DOI: 10.3390/bios12020083] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 06/12/2023]
Abstract
In this study, a fluorometric and colorimetric dual-readout lateral flow immunoassay (LFIA) using antibody functionalized polydopamine-coated gold nanoparticles (Au@PDAs) as a probe was developed for the detection of carbendazim (CBD). Colloidal gold nanoparticles (AuNPs) were coated with polydopamines (PDA) by the oxidation of dopamine to synthesize Au@PDA nanoparticles. The Au@PDA nanoparticles mediated ZnCdSe/ZnS quantum dots (QDs) fluorescence quenching and recovery, resulting in a reverse fluorescence enhancement detection format of CBD. The CBD detection was obtained by the competition between the CBD and the immobilized antigen for Au@PDAs labelled antibody binding, resulting in a significant fluorescence increase and colorimetry decrease corresponded to the concentration of CBD. Dual readout modes were incorporated into the LFIA using the colorimetry signal under natural light and the fluorescence signal under UV light. The cut-off value in the mode of the colorimetric signal and fluorometric signal for CBD detection was 0.5 μg/mL and 0.0156 μg/mL, respectively. The sensitivity of LFIA of the fluorescence mode was 32 times higher than that of the colorimetry mode. There was negligible cross reactivity obtained by using LFIA for the determination of thiabendazole, benomyl, thiophanate-methyl, and thiophanate-ethyl. Consistent and satisfactory results have been achieved by comparing the results of Au@PDAs-QDs-LFIA and liquid chromatography-tandem mass spectrometry (LC-MS/MS) testing spiked cucumber and strawberry samples, indicating good reliability of the Au@PDAs-QDs-LFIA.
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Affiliation(s)
- Xinxin Mao
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; (X.M.); (L.J.); (J.L.)
- Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base, Ministry of Agriculture, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (Y.W.); (H.Z.); (Y.Z.); (P.L.)
| | - Yulong Wang
- Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base, Ministry of Agriculture, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (Y.W.); (H.Z.); (Y.Z.); (P.L.)
| | - Lan Jiang
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; (X.M.); (L.J.); (J.L.)
| | - Hanxiaoya Zhang
- Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base, Ministry of Agriculture, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (Y.W.); (H.Z.); (Y.Z.); (P.L.)
| | - Yun Zhao
- Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base, Ministry of Agriculture, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (Y.W.); (H.Z.); (Y.Z.); (P.L.)
| | - Pengyan Liu
- Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base, Ministry of Agriculture, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (Y.W.); (H.Z.); (Y.Z.); (P.L.)
| | - Juanjuan Liu
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; (X.M.); (L.J.); (J.L.)
| | - Bruce D. Hammock
- Department of Entomology and Nematology, UCD Comprehensive Cancer Center, University of California, Davis, CA 95616, USA;
| | - Cunzheng Zhang
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; (X.M.); (L.J.); (J.L.)
- Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base, Ministry of Agriculture, Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China; (Y.W.); (H.Z.); (Y.Z.); (P.L.)
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China
- School of Biology and Food Engineering, Jiangsu University, Zhenjiang 212000, China
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Ahmed T, Yamanishi C, Kojima T, Takayama S. Aqueous Two-Phase Systems and Microfluidics for Microscale Assays and Analytical Measurements. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2021; 14:231-255. [PMID: 33950741 DOI: 10.1146/annurev-anchem-091520-101759] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Phase separation is a common occurrence in nature. Synthetic and natural polymers, salts, ionic liquids, surfactants, and biomacromolecules phase separate in water, resulting in an aqueous two-phase system (ATPS). This review discusses the properties, handling, and uses of ATPSs. These systems have been used for protein, nucleic acid, virus, and cell purification and have in recent years found new uses for small organics, polysaccharides, extracellular vesicles, and biopharmaceuticals. Analytical biochemistry applications such as quantifying protein-protein binding, probing for conformational changes, or monitoring enzyme activity have been performed with ATPSs. Not only are ATPSs biocompatible, they also retain their properties at the microscale, enabling miniaturization experiments such as droplet microfluidics, bacterial quorum sensing, multiplexed and point-of-care immunoassays, and cell patterning. ATPSs include coacervates and may find wider interest in the context of intracellular phase separation and origin of life. Recent advances in fundamental understanding and in commercial application are also considered.
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Affiliation(s)
- Tasdiq Ahmed
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
| | - Cameron Yamanishi
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
| | - Taisuke Kojima
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
| | - Shuichi Takayama
- Walter H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, Georgia 30332, USA;
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
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Recent advances in sensitivity enhancement for lateral flow assay. Mikrochim Acta 2021; 188:379. [PMID: 34647157 PMCID: PMC8513549 DOI: 10.1007/s00604-021-05037-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 09/25/2021] [Indexed: 12/04/2022]
Abstract
Conventional lateral flow assay (LFA) is typically performed by observing the color changes in the test lines by naked eyes, which achieves considerable commercial success and has a significant impact on the fields of food safety, environment monitoring, disease diagnosis, and other applications. However, this qualitative detection method is not very suitable for low levels of disease biomarkers' detection. Although many nanomaterials are used as new labels for LFA, additional readers limit their application to some extent. Fortunately, a lot of work has been done for improving the sensitivity of LFA. In this review, currently reported LFA sensitivity enhancement methods with an objective evaluation are summarized, such as sample pretreatment, the change of flow rate, and label evolution, and future development direction and challenges of LFAs are discussed.
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Zhang Y, Liu X, Wang L, Yang H, Zhang X, Zhu C, Wang W, Yan L, Li B. Improvement in Detection Limit for Lateral Flow Assay of Biomacromolecules by Test-Zone Pre-enrichment. Sci Rep 2020; 10:9604. [PMID: 32541787 PMCID: PMC7295814 DOI: 10.1038/s41598-020-66456-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 05/18/2020] [Indexed: 12/26/2022] Open
Abstract
Lateral flow assay (LFA) is one of the most prevalent commercially available techniques for point-of-care tests due to its simplicity, celerity, low cost and robust operation. However, conventional colorimetric LFAs have inferior limits of detection (LODs) compared to sophisticated laboratory-based assays. Here, we report a simple strategy of test-zone pre-enrichment to improve the LOD of LFA by loading samples before the conjugate pad assembly. The developed method enables visual LODs of miR-210 mimic and human chorionic gonadotropin protein, to be improved by 10–100 fold compared with a conventional LFA setup without introducing any additional instrument and reagent except for phosphate running buffer, while no obvious difference occurred for Aflatoxin B1 (AFB1). It takes about 6–8 min to enrich every 50 μL of sample diluted with phosphate running buffer, therefore we can get visual results within 20 min. We identified a parameter by modeling the entire process, the concentration of probe-analyte conjugate at test zone when signaling unit being loaded, to be important for the improvement of visual limit of detection. In addition, the test-zone pre-enrichment did not impair the selectivity when miR-210 mimic was adopted as target. Integrated with other optimization, amplification and modification of LFAs, the developed test-zone pre-enrichment method can be applied to further improve LOD of LFAs.
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Affiliation(s)
- Yi Zhang
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Collaborative innovation center of food safety and quality control in Jiangsu Province, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China.
| | - Xiao Liu
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Collaborative innovation center of food safety and quality control in Jiangsu Province, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China
| | - Lingling Wang
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Collaborative innovation center of food safety and quality control in Jiangsu Province, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China
| | - Hanjie Yang
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Collaborative innovation center of food safety and quality control in Jiangsu Province, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China
| | - Xiaoxiao Zhang
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Collaborative innovation center of food safety and quality control in Jiangsu Province, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China
| | - Chenglong Zhu
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Collaborative innovation center of food safety and quality control in Jiangsu Province, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China
| | - Wenlong Wang
- State Key Laboratory of Food Science and Technology, International Joint Laboratory on Food Safety, Collaborative innovation center of food safety and quality control in Jiangsu Province, Institute of Analytical Food Safety, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, PR China
| | - Lijing Yan
- Jiangnan University Hospital, Wuxi, 214122, PR China
| | - Bowei Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Research Center for Coastal Environmental Engineering and Technology, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, 264003, PR China
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6
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Research and Application Progress of Paper-based Microfluidic Sample Preconcentration. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2019. [DOI: 10.1016/s1872-2040(19)61203-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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7
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Tang RH, Liu LN, Zhang SF, Li A, Li Z. Modification of a nitrocellulose membrane with cellulose nanofibers for enhanced sensitivity of lateral flow assays: application to the determination of Staphylococcus aureus. Mikrochim Acta 2019; 186:831. [PMID: 31758272 DOI: 10.1007/s00604-019-3970-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 10/24/2019] [Indexed: 01/16/2023]
Abstract
Lateral flow assays, as a low-cost, simple, portable and disposable product of vitro diagnostic, are being widely used for point-of-care testing. However, the poor sensitivity of LFAs is the main challenge for commercialization. In order to enhance the sensitivity of LFAs, cellulose nanofibers (CNFs) have been integrated into LFAs to enhance the sensitivity of protein LFAs. A simple method is also presented to modify the properties of paper substrate by incorporating CNFs into a nitrocellulose membrane to enhance the sensitivity of nucleic acid LFAs. This method changes the pore size, porosity, surface groups and surface area of paper substrate and then increases the adsorption ability of biomolecules on paper substrate. The results indicate that the sensitivity of nucleic acid LFAs in Staphylococcus aureus testing achieves a 20-fold enhancement. Hence, we anticipate that this simple method has the potential for other paper-based devices to improve the performance. Graphical abstractA simple method is used to modify the properties of paper substrate by incorporating cellulose nanofibers (CNFs) into nitrocellulose (NC) membrane to enhance the sensitivity of nucleic acid LFAs.
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Affiliation(s)
- Rui Hua Tang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, People's Republic of China
- National Demonstration Center for Experimental Light Chemistry Engineering Education, Shaanxi University of Science & Technology, Xi'an, 710021, People's Republic of China
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Li Na Liu
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, People's Republic of China
- National Demonstration Center for Experimental Light Chemistry Engineering Education, Shaanxi University of Science & Technology, Xi'an, 710021, People's Republic of China
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Su Feng Zhang
- Shaanxi Province Key Laboratory of Papermaking Technology and Specialty Paper Development, Shaanxi University of Science & Technology, Xi'an, 710021, People's Republic of China
- Key Laboratory of Paper based Functional Materials of China National Light Industry, Shaanxi University of Science & Technology, Xi'an, 710021, People's Republic of China
| | - Ang Li
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China
| | - Zedong Li
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an, 710049, People's Republic of China.
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8
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Bradbury DW, Azimi M, Diaz AJ, Pan AA, Falktoft CH, Wu BM, Kamei DT. Automation of Biomarker Preconcentration, Capture, and Nanozyme Signal Enhancement on Paper-Based Devices. Anal Chem 2019; 91:12046-12054. [PMID: 31433941 DOI: 10.1021/acs.analchem.9b03105] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Infectious diseases remain one of the leading causes of deaths in developing countries because of a lack of basic sanitation, healthcare clinics, and centralized laboratories. Paper-based rapid diagnostic tests, such as the lateral-flow immunoassay (LFA), provide a promising alternative to the traditional laboratory-based tests; however, they typically suffer from having a poor sensitivity. Biomarker preconcentration and signal enhancement are two common methods to improve the sensitivity of paper-based assays. While effective, these methods often require multiple liquid handling steps which are not ideal for use by untrained personnel in a point-of-care setting. Our lab previously discovered the phenomenon of an aqueous two-phase system (ATPS) separating on paper, which allowed for the seamless integration of concentration and detection of biomarkers on the LFA. In this work, we have extended the functionality of an ATPS separating on paper to automate the sequential delivery of signal enhancement reagents in addition to concentrating biomarkers. The timing of reagent delivery was controlled by changing the initial composition of the ATPS. We applied this technology to automate biomarker concentration and nanozyme signal enhancement on the LFA, resulting in a 30-fold improvement in detection limit over the conventional LFA when detecting Escherichia coli, all while maintaining a single application step.
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Affiliation(s)
- Daniel W Bradbury
- Department of Bioengineering , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Milad Azimi
- Department of Bioengineering , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Alexia J Diaz
- Department of Bioengineering , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - April A Pan
- Department of Bioengineering , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Cecilie H Falktoft
- Department of Bioengineering , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Benjamin M Wu
- Department of Bioengineering , University of California, Los Angeles , Los Angeles , California 90095 , United States.,Division of Advanced Prosthodontics & Weintraub Center for Reconstructive Biotechnology School of Dentistry , University of California, Los Angeles , Los Angeles , California 90095 , United States
| | - Daniel T Kamei
- Department of Bioengineering , University of California, Los Angeles , Los Angeles , California 90095 , United States
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9
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Pereira DY, Wu CM, Lee SY, Lee E, Wu BM, Kamei DT. Controlling Macroscopic Phase Separation of Aqueous Two-Phase Polymer Systems in Porous Media. SLAS Technol 2019; 24:515-526. [PMID: 31361522 DOI: 10.1177/2472630319861369] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In previous work, our group discovered a phenomenon in which a mixed polymer-salt or mixed micellar aqueous two-phase system (ATPS) separates into its two constituent phases as it flows within paper. While these ATPSs worked well in their respective studies to concentrate the target biomarker and improve the sensitivity of the lateral-flow immunoassay, different ATPSs can be advantageous for new applications based on factors such as biomarker partitioning or biochemical compatibility between ATPS and sample components. However, since the mechanism of phase separation in porous media is not completely understood, introducing other ATPSs to paper is an unpredictable process that relies on trial and error experiments. This is especially true for polymer-polymer ATPSs in which the characteristics of the two phases appear quite similar. Therefore, our group aimed to develop semiquantitative guidelines for choosing ATPSs that can phase separate in paper. In this work, we evaluated the Washburn equation and its parameters as a potential mathematical framework to describe the flow behavior of polymer-salt and micellar ATPSs in fiberglass paper. We compared bulk phase fluid characteristics and identified the viscosity difference between the phases as a key determinant of the potential for phase separation in paper. We then used this parameter to predict the phase separation capabilities of polyethylene glycol (PEG)-dextran ATPSs in paper and control the composition of the leading and lagging phases. We also, for the first time, successfully demonstrated the phase separation phenomenon in hydrogels, thereby extending its application and potential benefits to an alternative porous medium.
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Affiliation(s)
- David Y Pereira
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Chloe M Wu
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - So Youn Lee
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Eumene Lee
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Benjamin M Wu
- Department of Bioengineering, University of California, Los Angeles, CA, USA
- Division of Advanced Prosthodontics & Weintraub Center for Reconstructive Biotechnology, School of Dentistry, University of California, Los Angeles, CA, USA
| | - Daniel T Kamei
- Department of Bioengineering, University of California, Los Angeles, CA, USA
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10
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Liu L, Yang D, Liu G. Signal amplification strategies for paper-based analytical devices. Biosens Bioelectron 2019; 136:60-75. [DOI: 10.1016/j.bios.2019.04.043] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 04/15/2019] [Accepted: 04/21/2019] [Indexed: 12/26/2022]
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11
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12
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Xie L, Zi X, Zeng H, Sun J, Xu L, Chen S. Low-cost fabrication of a paper-based microfluidic using a folded pattern paper. Anal Chim Acta 2018; 1053:131-138. [PMID: 30712558 DOI: 10.1016/j.aca.2018.12.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Revised: 11/26/2018] [Accepted: 12/03/2018] [Indexed: 01/20/2023]
Abstract
Despite that microfluidic paper-based analytical devices (μPADs) provide effective analytical platforms for point-of-care diagnosis in resource-limited areas, it remains challenging to achieve simple and low-cost fabrication of μPADs. A novel method for fabrication of μPADs is developed in this study using a folded polydimethylsiloxane (PDMS)-coated paper mask with a specific pattern to form a sandwich structure with inserted chromatographic paper. PDMS penetrates the target paper from the front and the back sides, and then is cured in the target paper to form legible channels. This method for prototyping μPADs has many favorable merits including simple operation without the need of trained personnel, fast fabrication and low cost. We further investigated colorimetric detection of melamine in the μPADs, and it showed a remarkable measurement with a detection limit of 0.1 ppm in aqueous solutions and liquid milk discriminated by the naked eye, which meets the detection limit required by USA and China. The fabricating strategy developed in this study is very promising and attractive for the development of simple μPADs for point-of-care applications, including diagnostic testing, food safety control and environmental monitoring.
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Affiliation(s)
- Liping Xie
- School of Sino-Dutch Biomedical and Information Engineering, Northeastern University, Shenyang, 110819, Liaoning, China.
| | - Xingyu Zi
- School of Sino-Dutch Biomedical and Information Engineering, Northeastern University, Shenyang, 110819, Liaoning, China
| | - Hedele Zeng
- School of Sino-Dutch Biomedical and Information Engineering, Northeastern University, Shenyang, 110819, Liaoning, China
| | - Jianjun Sun
- Department of Biological Sciences, Border Biomedical Research Center, University of Texas at El Paso, El Paso, TX, 79968, USA
| | - Lisheng Xu
- School of Sino-Dutch Biomedical and Information Engineering, Northeastern University, Shenyang, 110819, Liaoning, China
| | - Shuo Chen
- School of Sino-Dutch Biomedical and Information Engineering, Northeastern University, Shenyang, 110819, Liaoning, China
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13
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Damborský P, Koczula KM, Gallotta A, Katrlík J. Lectin-based lateral flow assay: proof-of-concept. Analyst 2018; 141:6444-6448. [PMID: 27767199 DOI: 10.1039/c6an01746k] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Lateral flow assays (LFAs) enable the simple and rapid detection and quantification of analytes and is popular for point-of-care (PoC), point-of-use and outdoor testing applications. LFAs typically depend on antibody or nucleic acid based recognition. We present the innovative concept of a LFA using lectins in the role of the biorecognition element. Lectins are a special kind of glycan-binding protein and the lectin-based LFA herein described was developed for the determination of the glycosylation of free prostate specific antigen (PSA). PSA is routinely used as a biomarker of prostate cancer (PCa) and the glycosylation status of PSA is a more specific marker of disease progress than only the PSA level. Using the lectin-based LFA we were able to detect α-2,6 sialic acid present in fPSA using Sambucus nigra (SNA) lectin. As a negative control, we employed Maackia amurensis lectin II (MAA II) which specifically binds α-2,3 sialic acid. The novel approach presented here can be applied to a wide range of biomarkers that have a significant impact on clinical diagnosis and prognosis, providing an alternative to standard lectin-based assays. The assay uses commercial components and is easily performed by applying a sample to the sampling pad on the lectin-based LFA strip, with results obtained within 10 minutes.
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Affiliation(s)
- Pavel Damborský
- Department of Glycobiotechnology, Center for Glycomics, Institute of Chemistry, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 84105, Slovakia.
| | - Katarzyna M Koczula
- Xeptagen SpA, Italy, VEGA Science Park - Building Auriga, Via delle Industrie, 9 - 30175 Marghera (VE), Italy.
| | - Andrea Gallotta
- Xeptagen SpA, Italy, VEGA Science Park - Building Auriga, Via delle Industrie, 9 - 30175 Marghera (VE), Italy.
| | - Jaroslav Katrlík
- Department of Glycobiotechnology, Center for Glycomics, Institute of Chemistry, Slovak Academy of Sciences, Dubravska cesta 9, Bratislava 84105, Slovakia.
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15
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Ye H, Xia X. Enhancing the sensitivity of colorimetric lateral flow assay (CLFA) through signal amplification techniques. J Mater Chem B 2018; 6:7102-7111. [PMID: 32254626 DOI: 10.1039/c8tb01603h] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Colorimetric lateral flow assay (CLFA) is one of a handful of diagnostic technologies that can be truly taken out of the laboratory for point-of-care testing without the need for any equipment and skilled personnel. Despite its simplicity and practicality, it remains a grand challenge to substantially enhance the detection sensitivity of CLFA without adding complexity. Such a limitation in sensitivity inhibits many critical applications such as early detection of significant cancers and severe infectious diseases. With the rapid development of materials science and nanotechnology, signal amplification techniques that hold great potential to break through the existing detection limit barrier of CLFA have been developed in recent years. This article specifically highlights these emerging techniques for CLFA development. The rationale behind and advantages and limitations of each technique are discussed. Perspectives on future research directions in this niche and important field are provided.
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Affiliation(s)
- Haihang Ye
- Department of Chemistry, University of Central Florida, Orlando, Florida 32816, USA.
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16
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Point-of-Care Sexually Transmitted Infection Diagnostics: Proceedings of the STAR Sexually Transmitted Infection-Clinical Trial Group Programmatic Meeting. Sex Transm Dis 2017; 44:211-218. [PMID: 28282646 PMCID: PMC5347466 DOI: 10.1097/olq.0000000000000572] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The STAR STI-CTG programmatic meeting reviewed point-of-care sexually transmitted infection diagnostics including current and emerging technologies, clinical and public health benefits, international applications, regulatory considerations, and future developments. The goal of the point-of-care (POC) sexually transmitted infection (STI) Diagnostics meeting was to review the state-of-the-art research and develop recommendations for the use of POC STI diagnostics. Experts from academia, government, nonprofit, and industry discussed POC diagnostics for STIs such as Chlamydia trachomatis, human papillomavirus, Neisseria gonorrhoeae, Trichomonas vaginalis, and Treponema pallidum. Key objectives included a review of current and emerging technologies, clinical and public health benefits, POC STI diagnostics in developing countries, regulatory considerations, and future areas of development. Key points of the meeting are as follows: (i) although some rapid point-of-care tests are affordable, sensitive, specific, easy to perform, and deliverable to those who need them for select sexually transmitted infections, implementation barriers exist at the device, patient, provider, and health system levels; (ii) further investment in research and development of point-of-care tests for sexually transmitted infections is needed, and new technologies can be used to improve diagnostic testing, test uptake, and treatment; (iii) efficient deployment of self-testing in supervised (ie, pharmacies, clinics, and so on) and/or unsupervised (ie, home, offices, and so on) settings could facilitate more screening and diagnosis that will reduce the burden of sexually transmitted infections; (iv) development of novel diagnostic technologies has outpaced the generation of guidance tools and documents issued by regulatory agencies; and (v) questions regarding quality management are emerging including the mechanism by which poor-performing diagnostics are removed from the market and quality assurance of self-testing is ensured.
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17
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Mosley GL, Pereira DY, Han Y, Lee SY, Wu CM, Wu BM, Kamei DT. Improved lateral-flow immunoassays for chlamydia and immunoglobulin M by sequential rehydration of two-phase system components within a paper-based diagnostic. Mikrochim Acta 2017. [DOI: 10.1007/s00604-017-2434-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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18
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Gong MM, Sinton D. Turning the Page: Advancing Paper-Based Microfluidics for Broad Diagnostic Application. Chem Rev 2017. [PMID: 28627178 DOI: 10.1021/acs.chemrev.7b00024] [Citation(s) in RCA: 311] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Infectious diseases are a major global health issue. Diagnosis is a critical first step in effectively managing their spread. Paper-based microfluidic diagnostics first emerged in 2007 as a low-cost alternative to conventional laboratory testing, with the goal of improving accessibility to medical diagnostics in developing countries. In this review, we examine the advances in paper-based microfluidic diagnostics for medical diagnosis in the context of global health from 2007 to 2016. The theory of fluid transport in paper is first presented. The next section examines the strategies that have been employed to control fluid and analyte transport in paper-based assays. Tasks such as mixing, timing, and sequential fluid delivery have been achieved in paper and have enabled analytical capabilities comparable to those of conventional laboratory methods. The following section examines paper-based sample processing and analysis. The most impactful advancement here has been the translation of nucleic acid analysis to a paper-based format. Smartphone-based analysis is another exciting development with potential for wide dissemination. The last core section of the review highlights emerging health applications, such as male fertility testing and wearable diagnostics. We conclude the review with the future outlook, remaining challenges, and emerging opportunities.
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Affiliation(s)
- Max M Gong
- Department of Mechanical and Industrial Engineering, University of Toronto , 5 King's College Road, Toronto, Ontario, Canada M5S 3G8.,Department of Biomedical Engineering, Wisconsin Institutes for Medical Research, University of Wisconsin-Madison , 1111 Highland Avenue, Madison, Wisconsin 53705, United States
| | - David Sinton
- Department of Mechanical and Industrial Engineering, University of Toronto , 5 King's College Road, Toronto, Ontario, Canada M5S 3G8
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Gong Y, Hu J, Choi JR, You M, Zheng Y, Xu B, Wen T, Xu F. Improved LFIAs for highly sensitive detection of BNP at point-of-care. Int J Nanomedicine 2017; 12:4455-4466. [PMID: 28670119 PMCID: PMC5479264 DOI: 10.2147/ijn.s135735] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Heart failure (HF) has become a major cause of morbidity and mortality with a significant global economic burden. Although well-established clinical tests could provide early diagnosis, access to these tests is limited in developing countries, where a relatively higher incidence of HF is present. This has prompted an urgent need for developing a cost-effective, rapid and robust diagnostic tool for point-of-care (POC) detection of HF. Lateral flow immunoassay (LFIA) has found widespread applications in POC diagnostics. However, the low sensitivity of LFIA limits its ability to detect important HF biomarkers (e.g., brain natriuretic peptide [BNP]) that are normally present in low concentration in blood. To address this issue, we developed an improved LFIA by optimizing the gold nanoparticle (GNP)–antibody conjugate conditions (e.g., the conjugate pH and the amount of added antibody), the diameter of GNP and the concentration of antibody embedded on the test line and modifying the structure of test strip. Through these improvements, the proposed test strip enabled the detection of BNP down to 0.1 ng/mL within 10–15 min, presenting ~15-fold sensitivity enhancement over conventional lateral flow assay. We also successfully applied our LFIA in the analysis of BNP in human serum samples, highlighting its potential use for clinical assessment of HF. The developed LFIA for BNP could rapidly rule out HF with the naked eye, offering tremendous potential for POC test and personalized medicine.
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Affiliation(s)
- Yan Gong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University.,Xi'an Diandi Biotech Company
| | - Jie Hu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University
| | - Jane Ru Choi
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University
| | - Minli You
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University
| | - Yamin Zheng
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University
| | - Bo Xu
- School of Finance and Economics, Xi'an Jiaotong University, Xi'an, People's Republic of China
| | | | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Department of Biomedical Engineering, School of Life Science and Technology, Xi'an Jiaotong University.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University
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20
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Sweet Strategies in Prostate Cancer Biomarker Research: Focus on a Prostate Specific Antigen. BIONANOSCIENCE 2017. [DOI: 10.1007/s12668-017-0397-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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21
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Choi JR, Yong KW, Tang R, Gong Y, Wen T, Yang H, Li A, Chia YC, Pingguan-Murphy B, Xu F. Lateral Flow Assay Based on Paper-Hydrogel Hybrid Material for Sensitive Point-of-Care Detection of Dengue Virus. Adv Healthc Mater 2017; 6. [PMID: 27860384 DOI: 10.1002/adhm.201600920] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 10/09/2016] [Indexed: 11/09/2022]
Abstract
Paper-based devices have been broadly used for the point-of-care detection of dengue viral nucleic acids due to their simplicity, cost-effectiveness, and readily observable colorimetric readout. However, their moderate sensitivity and functionality have limited their applications. Despite the above-mentioned advantages, paper substrates are lacking in their ability to control fluid flow, in contrast to the flow control enabled by polymer substrates (e.g., agarose) with readily tunable pore size and porosity. Herein, taking the benefits from both materials, the authors propose a strategy to create a hybrid substrate by incorporating agarose into the test strip to achieve flow control for optimal biomolecule interactions. As compared to the unmodified test strip, this strategy allows sensitive detection of targets with an approximately tenfold signal improvement. Additionally, the authors showcase the potential of functionality improvement by creating multiple test zones for semi-quantification of targets, suggesting that the number of visible test zones is directly proportional to the target concentration. The authors further demonstrate the potential of their proposed strategy for clinical assessment by applying it to their prototype sample-to-result test strip to sensitively and semi-quantitatively detect dengue viral RNA from the clinical blood samples. This proposed strategy holds significant promise for detecting various targets for diverse future applications.
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Affiliation(s)
- Jane Ru Choi
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC); Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Department of Biomedical Engineering; Faculty of Engineering; University of Malaya; Lembah Pantai; 50603 Kuala Lumpur Malaysia
| | - Kar Wey Yong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC); Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Department of Biomedical Engineering; Faculty of Engineering; University of Malaya; Lembah Pantai; 50603 Kuala Lumpur Malaysia
| | - Ruihua Tang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC); Xi'an Jiaotong University; Xi'an 710049 P. R. China
- School of Life Sciences; Northwestern Polytechnical University; Xi'an 710072 P. R. China
| | - Yan Gong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC); Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Xi'an Diandi Biotech Company; Xi'an 710049 P. R. China
| | - Ting Wen
- Xi'an Diandi Biotech Company; Xi'an 710049 P. R. China
| | - Hui Yang
- School of Life Sciences; Northwestern Polytechnical University; Xi'an 710072 P. R. China
| | - Ang Li
- Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research; College of Stomatology; Xi'an Jiaotong University; Xi'an 710049 P. R. China
| | - Yook Chin Chia
- Department of Primary Care Medicine; University of Malaya Primary Care Research Group; Faculty of Medicine; University of Malaya; Lembah Pantai; 50603 Kuala Lumpur Malaysia
| | - Belinda Pingguan-Murphy
- Department of Biomedical Engineering; Faculty of Engineering; University of Malaya; Lembah Pantai; 50603 Kuala Lumpur Malaysia
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education; School of Life Science and Technology; Xi'an Jiaotong University; Xi'an 710049 P. R. China
- Bioinspired Engineering and Biomechanics Center (BEBC); Xi'an Jiaotong University; Xi'an 710049 P. R. China
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22
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Mosley GL, Nguyen P, Wu BM, Kamei DT. Development of quantitative radioactive methodologies on paper to determine important lateral-flow immunoassay parameters. LAB ON A CHIP 2016; 16:2871-81. [PMID: 27364421 DOI: 10.1039/c6lc00518g] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The lateral-flow immunoassay (LFA) is a well-established diagnostic technology that has recently seen significant advancements due in part to the rapidly expanding fields of paper diagnostics and paper-fluidics. As LFA-based diagnostics become more complex, it becomes increasingly important to quantitatively determine important parameters during the design and evaluation process. However, current experimental methods for determining these parameters have certain limitations when applied to LFA systems. In this work, we describe our novel methods of combining paper and radioactive measurements to determine nanoprobe molarity, the number of antibodies per nanoprobe, and the forward and reverse rate constants for nanoprobe binding to immobilized target on the LFA test line. Using a model LFA system that detects for the presence of the protein transferrin (Tf), we demonstrate the application of our methods, which involve quantitative experimentation and mathematical modeling. We also compare the results of our rate constant experiments with traditional experiments to demonstrate how our methods more appropriately capture the influence of the LFA environment on the binding interaction. Our novel experimental approaches can therefore more efficiently guide the research process for LFA design, leading to more rapid advancement of the field of paper-based diagnostics.
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Affiliation(s)
- Garrett L Mosley
- Department of Bioengineering, University of California, Los Angeles, CA 90095, USA.
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23
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Ricks KM, Adams NM, Scherr TF, Haselton FR, Wright DW. Direct transfer of HRPII-magnetic bead complexes to malaria rapid diagnostic tests significantly improves test sensitivity. Malar J 2016; 15:399. [PMID: 27495329 PMCID: PMC4975893 DOI: 10.1186/s12936-016-1448-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 07/20/2016] [Indexed: 12/24/2022] Open
Abstract
Background The characteristic ease of use, rapid time to result, and low cost of malaria rapid diagnostic tests (RDTs) promote their widespread use at the point-of-care for malaria detection and surveillance. However, in many settings, the success of malaria elimination campaigns depends on point-of-care diagnostics with greater sensitivity than currently available RDTs. To address this need, a sample preparation method was developed to deliver more biomarkers onto a malaria RDT by concentrating the biomarker from blood sample volumes that are too large to be directly applied to a lateral flow strip. Methods In this design, Ni–NTA-functionalized magnetic beads captured the Plasmodium falciparum biomarker HRPII from a P. falciparum D6 culture spiked blood sample. This transfer of magnetic beads to the RDT was facilitated by an inexpensive 3D-printed apparatus that aligned the sample tube with the sample deposition pad and a magnet beneath the RDT. Biomarkers were released from the bead surface onto the lateral flow strip using imidazole-spiked running buffer. Kinetics of HRPII binding to the Ni–NTA beads as a function of blood sample volume were explored prior to determining the effect of the proposed method on the limit of detection of Paracheck RDTs. Results More than 80 % of HRPII biomarkers were extracted from blood sample volumes ranging from 25 to 250 µL. The time required to reach 80 % binding ranged from 5 to 60 min, depending on sample volume. Using 250 μL of blood and a 30-min biomarker binding time, the limit of detection of the Paracheck Pf RDT brand was improved by 21-fold, resulting in a limit of detection below 1 parasite/μL. Conclusions This approach has the sensitivity and simplicity required to assist in malaria elimination campaigns in settings with limited access to clinical and laboratory resources. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1448-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Keersten M Ricks
- Department of Chemistry, Vanderbilt University, Nashville, TN, 37235, USA
| | - Nicholas M Adams
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - Thomas F Scherr
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - Frederick R Haselton
- Department of Chemistry, Vanderbilt University, Nashville, TN, 37235, USA.,Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - David W Wright
- Department of Chemistry, Vanderbilt University, Nashville, TN, 37235, USA.
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24
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Phan JC, Nehilla BJ, Srinivasan S, Coombs RW, Woodrow KA, Lai JJ. Human Immunodeficiency Virus (HIV) Separation and Enrichment via the Combination of Antiviral Lectin Recognition and a Thermoresponsive Reagent System. Pharm Res 2016; 33:2411-20. [PMID: 27401412 DOI: 10.1007/s11095-016-1980-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 06/21/2016] [Indexed: 11/28/2022]
Abstract
PURPOSE In order to improve the detection limit of existing HIV diagnostic assays, we explored the use of a temperature-responsive magnetic nanoparticle reagent system in conjunction with cyanovirin-N for HIV recognition to rapidly and efficiently concentrate viral particles from larger sample volumes, ~ 1 ml. METHODS Cyanovirin-N (CVN) mutant, Q62C, was expressed, biotinylated, and then complexed with a thermally responsive polymer-streptavidin conjugate. Confirmation of protein expression/activity was performed using matrix assisted laser desorption/ionization (MALDI) and a TZM-bl HIV inhibition assay. Biotinylated CVN mutant recognition with gp120 was characterized using surface plasmon resonance (SPR). Virus separation and enrichment using a thermoresponsive magnetic nanoparticle reagent system were measured using RT-PCR. RESULTS Biotinylated Q62C exhibited a KD of 0.6 nM to gp120. The temperature-responsive binary reagent system achieved a maximum viral capture of nearly 100% HIV, 1 × 10(5) virus copies in 100 μl, using pNIPAAm-Q62C within 30 minutes. Additionally, the same reagent system achieved nearly 9-fold enrichment by processing a 10-times larger sample of 1000 μl (Fig. 3). CONCLUSION This work demonstrated a temperature-responsive reagent system that provides enrichment of HIV using antiviral lectin CVN for recognition, which is potentially amenable for use in point-of-care settings.
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Affiliation(s)
- Joseph C Phan
- Department of Bioengineering, University of Washington, Box 355061, Seattle, Washington, 98195, USA
| | - Barrett J Nehilla
- Nexgenia, Inc., 4000 Mason Rd., Fluke Hall, Suite 312-1, Seattle, Washington, 98195, USA
| | - Selvi Srinivasan
- Department of Bioengineering, University of Washington, Box 355061, Seattle, Washington, 98195, USA
| | - Robert W Coombs
- Division of Allergy and Infectious Diseases, University of Washington, Seattle, Washington, 98104, USA
| | - Kim A Woodrow
- Department of Bioengineering, University of Washington, Box 355061, Seattle, Washington, 98195, USA.
| | - James J Lai
- Department of Bioengineering, University of Washington, Box 355061, Seattle, Washington, 98195, USA.
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25
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Han SI, Hwang KS, Kwak R, Lee JH. Microfluidic paper-based biomolecule preconcentrator based on ion concentration polarization. LAB ON A CHIP 2016; 16:2219-27. [PMID: 27199301 DOI: 10.1039/c6lc00499g] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Microfluidic paper-based analytical devices (μPADs) for molecular detection have great potential in the field of point-of-care diagnostics. Currently, a critical problem being faced by μPADs is improving their detection sensitivity. Various preconcentration processes have been developed, but they still have complicated structures and fabrication processes to integrate into μPADs. To address this issue, we have developed a novel paper-based preconcentrator utilizing ion concentration polarization (ICP) with minimal addition on lateral-flow paper. The cation selective membrane (i.e., Nafion) is patterned on adhesive tape, and this tape is then attached to paper-based channels. When an electric field is applied across the Nafion, ICP is initiated to preconcentrate the biomolecules in the paper channel. Departing from previous paper-based preconcentrators, we maintain steady lateral fluid flow with the separated Nafion layer; as a result, fluorescent dyes and proteins (FITC-albumin and bovine serum albumin) are continuously delivered to the preconcentration zone, achieving high preconcentration performance up to 1000-fold. In addition, we demonstrate that the Nafion-patterned tape can be integrated with various geometries (multiplexed preconcentrator) and platforms (string and polymer microfluidic channel). This work would facilitate integration of various ICP devices, including preconcentrators, pH/concentration modulators, and micro mixers, with steady lateral flows in paper-based platforms.
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Affiliation(s)
- Sung Il Han
- Department of Electrical Engineering, Kwangwoon University, Seoul, 139-701, Republic of Korea.
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26
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Tang RH, Yang H, Choi JR, Gong Y, Feng SS, Pingguan-Murphy B, Huang QS, Shi JL, Mei QB, Xu F. Advances in paper-based sample pretreatment for point-of-care testing. Crit Rev Biotechnol 2016; 37:411-428. [DOI: 10.3109/07388551.2016.1164664] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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27
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Choi JR, Liu Z, Hu J, Tang R, Gong Y, Feng S, Ren H, Wen T, Yang H, Qu Z, Pingguan-Murphy B, Xu F. Polydimethylsiloxane-Paper Hybrid Lateral Flow Assay for Highly Sensitive Point-of-Care Nucleic Acid Testing. Anal Chem 2016; 88:6254-64. [PMID: 27012657 DOI: 10.1021/acs.analchem.6b00195] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
In nucleic acid testing (NAT), gold nanoparticle (AuNP)-based lateral flow assays (LFAs) have received significant attention due to their cost-effectiveness, rapidity, and the ability to produce a simple colorimetric readout. However, the poor sensitivity of AuNP-based LFAs limits its widespread applications. Even though various efforts have been made to improve the assay sensitivity, most methods are inappropriate for integration into LFA for sample-to-answer NAT at the point-of-care (POC), usually due to the complicated fabrication processes or incompatible chemicals used. To address this, we propose a novel strategy of integrating a simple fluidic control strategy into LFA. The strategy involves incorporating a piece of paper-based shunt and a polydimethylsiloxane (PDMS) barrier to the strip to achieve optimum fluidic delays for LFA signal enhancement, resulting in 10-fold signal enhancement over unmodified LFA. The phenomena of fluidic delay were also evaluated by mathematical simulation, through which we found the movement of fluid throughout the shunt and the tortuosity effects in the presence of PDMS barrier, which significantly affect the detection sensitivity. To demonstrate the potential of integrating this strategy into a LFA with sample-in-answer-out capability, we further applied this strategy into our prototype sample-to-answer LFA to sensitively detect the Hepatitis B virus (HBV) in clinical blood samples. The proposed strategy offers great potential for highly sensitive detection of various targets for wide application in the near future.
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Affiliation(s)
- Jane Ru Choi
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,Department of Biomedical Engineering, Faculty of Engineering, University of Malaya , Lembah Pantai, 50603 Kuala Lumpur, Malaysia.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
| | - Zhi Liu
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education, School of Energy and Power Engineering, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
| | - Jie Hu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
| | - Ruihua Tang
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,School of Life Sciences, Northwestern Polytechnical University , Xi'an, Shaanxi 710072, PR China.,Key Laboratory of Space Bioscience and Biotechnology, Northwestern Polytechnical University , Xi'an, Shaanxi 710072, PR China
| | - Yan Gong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
| | - Shangsheng Feng
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,MOE Key Laboratory of Multifunctional Materials and Structures (LMMS), School of Aerospace, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,State Key Laboratory of Mechanical Structure Strength and Vibration, School of Aerospace, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
| | - Hui Ren
- Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Xi'an Jiaotong University , Xi'an, Shaanxi 710061, PR China
| | - Ting Wen
- Xi'an Diandi Biotech Company , Xi'an, Shaanxi 710049, PR China
| | - Hui Yang
- School of Life Sciences, Northwestern Polytechnical University , Xi'an, Shaanxi 710072, PR China.,Key Laboratory of Space Bioscience and Biotechnology, Northwestern Polytechnical University , Xi'an, Shaanxi 710072, PR China
| | - Zhiguo Qu
- Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education, School of Energy and Power Engineering, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
| | - Belinda Pingguan-Murphy
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya , Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China.,Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University , Xi'an, Shaanxi 710049, PR China
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Tang R, Yang H, Choi JR, Gong Y, Hu J, Feng S, Pingguan-Murphy B, Mei Q, Xu F. Improved sensitivity of lateral flow assay using paper-based sample concentration technique. Talanta 2016; 152:269-76. [PMID: 26992520 DOI: 10.1016/j.talanta.2016.02.017] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 02/01/2016] [Accepted: 02/05/2016] [Indexed: 11/29/2022]
Abstract
Lateral flow assays (LFAs) hold great promise for point-of-care testing, especially in resource-poor settings. However, the poor sensitivity of LFAs limits their widespread applications. To address this, we developed a novel device by integrating dialysis-based concentration method into LFAs. The device successfully achieved 10-fold signal enhancement in Human Immunodeficiency Virus (HIV) nucleic acid detection with a detection limit of 0.1 nM and 4-fold signal enhancement in myoglobin (MYO) detection with a detection limit of 1.56 ng/mL in less than 25 min. This simple, low-cost and portable integrated device holds great potential for highly sensitive detection of various target analytes for medical diagnostics, food safety analysis and environmental monitoring.
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Affiliation(s)
- Ruihua Tang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, PR China; Key Laboratory for Space Bioscience and Biotechnology, Northwestern Polytechnical University, Xi'an 710072, PR China; The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China
| | - Hui Yang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, PR China; Key Laboratory for Space Bioscience and Biotechnology, Northwestern Polytechnical University, Xi'an 710072, PR China.
| | - Jane Ru Choi
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China; Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Yan Gong
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China
| | - Jie Hu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China
| | - Shangsheng Feng
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China
| | - Belinda Pingguan-Murphy
- Department of Biomedical Engineering, Faculty of Engineering, University of Malaya, Lembah Pantai, 50603 Kuala Lumpur, Malaysia
| | - Qibing Mei
- School of Life Sciences, Northwestern Polytechnical University, Xi'an 710072, PR China; Key Laboratory for Space Bioscience and Biotechnology, Northwestern Polytechnical University, Xi'an 710072, PR China
| | - Feng Xu
- The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an 710049, PR China; Bioinspired Engineering and Biomechanics Center (BEBC), Xi'an Jiaotong University, Xi'an 710049, PR China.
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Eltzov E, Guttel S, Low Yuen Kei A, Sinawang PD, Ionescu RE, Marks RS. Lateral Flow Immunoassays - from Paper Strip to Smartphone Technology. ELECTROANAL 2015. [DOI: 10.1002/elan.201500237] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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30
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Cheung SF, Cheng SKL, Kamei DT. Paper-Based Systems for Point-of-Care Biosensing. ACTA ACUST UNITED AC 2015; 20:316-33. [DOI: 10.1177/2211068215577197] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Indexed: 02/06/2023]
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31
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Pereira DY, Chiu RYT, Zhang SCL, Wu BM, Kamei DT. Single-step, paper-based concentration and detection of a malaria biomarker. Anal Chim Acta 2015; 882:83-9. [PMID: 26043095 DOI: 10.1016/j.aca.2015.04.040] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 04/15/2015] [Accepted: 04/20/2015] [Indexed: 10/23/2022]
Abstract
The lateral-flow immunoassay (LFA) is an inexpensive and rapid paper-based assay that can potentially detect infectious disease biomarkers in resource-poor settings. Despite its many advantages that make it suitable for point-of-care diagnosis, LFA is limited by its inferior sensitivity relative to sophisticated laboratory-based assays. Our group previously introduced the use of a micellar aqueous two-phase system (ATPS), comprised of the nonionic Triton X-114 surfactant, to concentrate biomarkers in a sample and enhance their detection with LFA. However, achieving complete phase separation and target concentration using the Triton X-114 system required many hours, and the concentrated sample needed to be manually extracted and applied to LFA. Here, we successfully integrated the concentration and detection steps into a single step that occurs entirely within a portable paper-based diagnostic strip. In a novel approach, we applied the micellar ATPS to a 3-D paper design and effectively reduced the macroscopic phase separation time from 8 h to approximately 3 min. The 3-D design was integrated with LFA to simultaneously concentrate and detect Plasmodium lactate dehydrogenase (pLDH), a malaria biomarker, in both phosphate-buffered saline and fetal bovine serum within 20 min at room temperature. Compared to a conventional LFA setup with a pLDH detection limit of 10 ng μL(-1), our single-step diagnostic successfully detected pLDH at 1.0 ng μL(-1), demonstrating a 10-fold detection limit improvement and resulting in a sensitive and user-friendly assay that can be used at the point-of-care. The integration of a micellar ATPS and LFA represents a new platform that can improve and promote the use of paper-based diagnostic assays for malaria and other diseases within resource-poor settings.
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Affiliation(s)
- David Y Pereira
- Department of Bioengineering, University of California, 420 Westwood Plaza, 5121J Engineering V, P.O. Box 951600, Los Angeles, CA 90095-1600, USA
| | - Ricky Y T Chiu
- Department of Bioengineering, University of California, 420 Westwood Plaza, 5121J Engineering V, P.O. Box 951600, Los Angeles, CA 90095-1600, USA
| | - Samantha C L Zhang
- Department of Bioengineering, University of California, 420 Westwood Plaza, 5121J Engineering V, P.O. Box 951600, Los Angeles, CA 90095-1600, USA
| | - Benjamin M Wu
- Department of Bioengineering, University of California, 420 Westwood Plaza, 5121J Engineering V, P.O. Box 951600, Los Angeles, CA 90095-1600, USA; Division of Advanced Prosthodontics & Weintraub Center for Reconstructive Biotechnology, UCLA School of Dentistry, Los Angeles, CA 90095-1600, USA
| | - Daniel T Kamei
- Department of Bioengineering, University of California, 420 Westwood Plaza, 5121J Engineering V, P.O. Box 951600, Los Angeles, CA 90095-1600, USA.
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32
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Petryayeva E, Algar WR. Toward point-of-care diagnostics with consumer electronic devices: the expanding role of nanoparticles. RSC Adv 2015. [DOI: 10.1039/c4ra15036h] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
A review of the role that nanoparticles can play in point-of-care diagnostics that utilize consumer electronic devices such as cell phones and smartphones for readout, including an overview of important concepts and examples from the literature.
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Affiliation(s)
| | - W. Russ Algar
- Department of Chemistry
- University of British Columbia
- Vancouver
- Canada
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Yang RJ, Pu HH, Wang HL. Ion concentration polarization on paper-based microfluidic devices and its application to preconcentrate dilute sample solutions. BIOMICROFLUIDICS 2015; 9:014122. [PMID: 25759755 PMCID: PMC4336261 DOI: 10.1063/1.4913366] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 02/09/2015] [Indexed: 05/18/2023]
Abstract
Microfluidic paper-based analytical devices (μPADs) are a promising solution for a wide range of point-of-care applications. The feasibility of inducing ion concentration polarization (ICP) on μPADs has thus far attracted little attention. Accordingly, this study commences by demonstrating the ICP phenomenon in a μPAD with a Nafion ion-selective membrane. We are the first to measure the current-voltage curve on a Nafion-coated μPAD in order to indicate that the ion depletion occurs and the ICP is triggered when the current reaches the limiting current. The ICP effect is then exploited to preconcentrate fluorescein on μPADs incorporating straight and convergent channels. By an optimal geometric design, it is shown that the convergent channel results in a greater preconcentration effect than the straight channel. Specifically, a 20-fold enhancement in the sample concentration is achieved after 130 s given an initial concentration of [Formula: see text] M and an external potential of 50 V. By contrast, the straight channel yields only a 10-fold improvement in the concentration after 180 s. Further, the practical feasibility of the proposed convergent-channel μPAD is demonstrated using fluorescein isothiocyanate labeled bovine serum albumin. The experimental results show that a 15-fold enhancement of the initial sample concentration ([Formula: see text] M) is obtained after 120 s given an external potential of 50 V.
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Affiliation(s)
- Ruey-Jen Yang
- Department of Engineering Science, National Cheng Kung University , Tainan, Taiwan
| | - Hao-Hsuan Pu
- Department of Engineering Science, National Cheng Kung University , Tainan, Taiwan
| | - Hsiang-Li Wang
- Department of Engineering Science, National Cheng Kung University , Tainan, Taiwan
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Wu CY, Adeyiga O, Lin J, Di Carlo D. Research highlights: increasing paper possibilities. LAB ON A CHIP 2014; 14:3258-3261. [PMID: 25048950 DOI: 10.1039/c4lc90067g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this issue we highlight three recent papers that demonstrate new strategies to extend the capabilities of paper microfluidics. Paper (a mesh of porous fibers) has a long history as a substrate to perform biomolecular assays. Traditional lateral flow immunoassays (LFAs) are widely used for rapid diagnostic tests, and perform well when a yes or no answer is required and the analyte of interest is at relatively high concentrations. High concentrations are required because usually only a small volume of analyte-containing fluid flows past the detection region, leading to a limited signal. Further, the small pores within paper matrices prevent the use of paper to control the flow of larger particles and cells, limiting the use of paper microfluidics for cell-based diagnostics. The work we highlight addresses these important unmet challenges in paper microfluidics: enriching low concentration analytes to a higher concentration in a smaller volume that can be processed effectively, and using paper to pump flows in larger channels amenable to cells. Applying these new approaches may allow diagnosis of disease states currently technically unachievable using current LFA systems, while maintaining many of the "un-instrumented" advantages of an assay on self-wicking paper.
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Affiliation(s)
- Chueh-Yu Wu
- Department of Bioengineering, California NanoSystems Institute, Jonsson Comprehensive Cancer Center, University of California Los Angeles, 420 Westwood Plaza, 5121 Engineering V, Box 951600, Los Angeles, California 90095, USA.
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