1
|
Hu C, Xie B, Li H, Xiao D. A five-electrode capacitively coupled contactless conductivity detector with a low limit of detection. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2023; 15:2253-2261. [PMID: 37128967 DOI: 10.1039/d3ay00328k] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The conductivity detector is a broadly used device that allows for the highly efficient detection of analytes, and continuous efforts have been directed toward lowering the limit of detection. In this study, a five-electrode capacitively coupled contactless conductivity detector (TIC4D) is proposed, which uses copper mesh between the electrodes for a grounding shield to reduce the interference of stray capacitance and noise. After adding the copper mesh shield, the difference value between the response signal and baseline at low KCl concentration is effectively increased, achieving 33 mV for 10-9 M KCl solution. Meanwhile, for the unshielded detector, the difference is only 18 mV for the KCl solution at the same concentration. The response signal shows a linear function of the logarithm at the range of 10-4 M to 10-5 M KCl solution, and the TIC4D detector displays a higher slope (0.8448) than the conventional single-input capacitively coupled contactless conductivity detector (C4D: 0.5579) and dual-input capacitively coupled contactless conductivity detectors (DIC4D: 0.6173). Moreover, two TIC4D detectors are combined to achieve a dual-channel six-input differential capacitively coupled contactless conductivity detector (SIDC4D), reducing the high baseline levels caused by the multi-signal input. By differentially amplifying the output signal, the high baseline levels and noise interference can be effectively reduced. For the 10-3 M KCl solution, the ratio of the response signal to baseline for SIDC4D can reach 8.500, almost 7 times that of TIC4D, and a lower limit of detection (LOD) of 3 × 10-10 M is also achieved. This work may open a new door based on coupled contactless conductivity for detection performance.
Collapse
Affiliation(s)
- Chunqiong Hu
- College of Chemical Engineering, Sichuan University, Chengdu 610064, China.
| | - Bo Xie
- College of Chemical Engineering, Sichuan University, Chengdu 610064, China.
| | - Hongmei Li
- College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Dan Xiao
- College of Chemical Engineering, Sichuan University, Chengdu 610064, China.
- College of Chemistry, Sichuan University, Chengdu 610064, China
| |
Collapse
|
2
|
Wang C, Huang J, Ji H, Huang Z. Response Characteristics of Contactless Impedance Detection (CID) Sensor on Slug Flow in Small Channels: The Investigation on Slug Separation Distance. SENSORS (BASEL, SWITZERLAND) 2022; 22:8987. [PMID: 36433583 PMCID: PMC9692662 DOI: 10.3390/s22228987] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/04/2022] [Accepted: 11/18/2022] [Indexed: 06/16/2023]
Abstract
In recent years, CID sensors have displayed great development potential in parameter measurement of gas-liquid two-phase flow in small channels. However, the fundamental/mechanism research on the response characteristics of CID sensors is relatively insufficient. This work focuses on the investigation of the influence of separation distance between slugs on the impedance (real part, imaginary part and amplitude) response characteristics of slug flow in small channels. Experiments were carried out with the CID sensors in four small channels with inner pipe diameters of 1.96 mm, 2.48 mm, 3.02 mm and 3.54 mm, respectively. The experimental results show that for a CID sensor, the slug separation distance has significant influence on the impedance response characteristics. There is a critical value of slug separation distance. When the slug separation distance is larger than the critical value, the impedance response characteristics of each slug can be considered independent of each other, i.e., there is no interaction between the slugs. When the slug separation distance is less than the critical value, the impedance response characteristics show obvious interaction between the slugs. It is indicated that the ratios of the critical values to the pipe inner diameters are approximate 100.
Collapse
|
3
|
Development of a Contactless Conductivity Sensor in Flowing Micro Systems for Cerium Nitrate. Processes (Basel) 2022. [DOI: 10.3390/pr10102075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Impedance spectroscopy has a high potential to detect chemical reactions in flowing systems. In this work, the approach using impedance spectroscopy as a possible analytical tool for a continuous hydrothermal syntheses (CHTS) is presented. With the CHTS-process, it is possible to produce metalloxide nanoparticles with a close particle size distribution and specific surface properties. For this, it is necessary to evaluate the electrode geometry, frequency and other factors influencing the impedance with respect to concentration measurements. In case of frequency-sweep measurements possible electrode geometries for C4D-Sensors (capacitively coupled contactless conductivity detection) are evaluated. Then distinguishability and reproducibility are tested applying titration measurements to show the ability for concentration detection in constant flow systems. The possibility to measure concentration changes in flowing systems in a reproducible and fast manner as well as with high distinguishability for the test solution cerium nitrate will be presented. Furthermore, the major influencing-factors like electrode geometry, frequency etc. could be determined. It has been shown that with increasing electrode spacing and electrode width, the distinguishability of the concentrations increases and shifts them to lower frequencies.
Collapse
|
4
|
Huyen My Dang T, Quoc Hoang A, Huy Nguyen Q, Chi Le D, Duc Mai T, Nhi Do Y, Anh Kieu V, Khanh Cao C, Minh Hien Lu T, Minh Thu Nguyen T, Pham B, Anh Huong Nguyen T. Simultaneous determination of vitamin B 6 and magnesium using capillary electrophoresis coupled with contactless conductivity detection: Method development, validation, and application to pharmaceutical and nutraceutical samples. J Chromatogr B Analyt Technol Biomed Life Sci 2022; 1210:123471. [PMID: 36174264 DOI: 10.1016/j.jchromb.2022.123471] [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: 08/07/2022] [Revised: 09/09/2022] [Accepted: 09/13/2022] [Indexed: 11/29/2022]
Abstract
Vitamins and minerals are usually incorporated in pharmaceutical and nutraceutical products, but a simple, rapid, and inexpensive analytical method for their simultaneous determination is still lacking. In this study, we developed a quantification method for pyridoxine (vitamin B6) and magnesium (Mg) by using purpose-made capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) instrument. Main analytical conditions include: fused silica capillary (total length 55 cm, effective length 40 cm, inner diameter 50 μm); background electrolyte consisted of 10 mM L-arginine/acetic acid (pH 5) with 20% acetonitrile; separation voltage + 20 kV; hydrodynamic injection (siphoning at 20 cm in 25 s). Detection limits of vitamin B6 and Mg were 1 and 0.1 mg/L, respectively. Good linearity (R2 > 0.999) was observed for vitamin B6 and Mg calibration curves over concentration ranges of 3-100 and 0.3-200 mg/L, respectively. The method was applied to analyze vitamin B6 and Mg in several pharmaceutical and nutraceutical samples. The analytical results obtained by our method were in good agreement with reference methods (i.e., HPLC for vitamin B6 and ICP-OES for Mg). High-efficient and low-cost CE-C4D method can accordingly serve as a promising tool for concurrent analysis of inorganic and organic species in pharmaceutical and nutraceutical analysis.
Collapse
Affiliation(s)
- Thi Huyen My Dang
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Anh Quoc Hoang
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam.
| | - Quang Huy Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam; Faculty of Pharmacy, University of Medicine and Pharmacy, Thai Nguyen University, 284, Luong Ngoc Quyen, Thai Nguyen 24000, Vietnam
| | - Dinh Chi Le
- Department of Analytical Chemistry and Toxicology, Hanoi University of Pharmacy, 13-15 Le Thanh Tong, Hanoi 10000, Vietnam
| | - Thanh Duc Mai
- Université Paris-Saclay, CNRS, Institut Galien Paris-Saclay, 92296, Châtenay-Malabry, France
| | - Yen Nhi Do
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Van Anh Kieu
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Cong Khanh Cao
- National Institute for Food Control (NIFC), 65, Pham Than Duat, Hanoi 10000, Vietnam
| | - Thi Minh Hien Lu
- National Institute for Food Control (NIFC), 65, Pham Than Duat, Hanoi 10000, Vietnam
| | - Thi Minh Thu Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Bach Pham
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam
| | - Thi Anh Huong Nguyen
- Faculty of Chemistry, University of Science, Vietnam National University, Hanoi, 19, Le Thanh Tong, Hanoi 10000, Vietnam.
| |
Collapse
|
5
|
Abstract
Isotachophoresis (ITP) is a versatile electrophoretic technique that can be used for sample preconcentration, separation, purification, and mixing, and to control and accelerate chemical reactions. Although the basic technique is nearly a century old and widely used, there is a persistent need for an easily approachable, succinct, and rigorous review of ITP theory and analysis. This is important because the interest and adoption of the technique has grown over the last two decades, especially with its implementation in microfluidics and integration with on-chip chemical and biochemical assays. We here provide a review of ITP theory starting from physicochemical first-principles, including conservation of species, conservation of current, approximation of charge neutrality, pH equilibrium of weak electrolytes, and so-called regulating functions that govern transport dynamics, with a strong emphasis on steady and unsteady transport. We combine these generally applicable (to all types of ITP) theoretical discussions with applications of ITP in the field of microfluidic systems, particularly on-chip biochemical analyses. Our discussion includes principles that govern the ITP focusing of weak and strong electrolytes; ITP dynamics in peak and plateau modes; a review of simulation tools, experimental tools, and detection methods; applications of ITP for on-chip separations and trace analyte manipulation; and design considerations and challenges for microfluidic ITP systems. We conclude with remarks on possible future research directions. The intent of this review is to help make ITP analysis and design principles more accessible to the scientific and engineering communities and to provide a rigorous basis for the increased adoption of ITP in microfluidics.
Collapse
Affiliation(s)
- Ashwin Ramachandran
- Department of Aeronautics and Astronautics, Stanford University, Stanford, California 94305, United States
| | - Juan G Santiago
- Department of Mechanical Engineering, Stanford University, Stanford, California 94305, United States
| |
Collapse
|
6
|
Nie H, Li Z, Wang X, Gu R, Yuan H, Guo Y, Xiao D. An improved dual-channel capacitively coupled contactless conductivity detector with high detection performance. Analyst 2022; 147:2106-2114. [PMID: 35470820 DOI: 10.1039/d2an00330a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Conductivity detectors are widely used electrochemical sensors. It has long been a goal of researchers to improve detection performance. In this contribution, we propose a multi-input capacitively coupled contactless conductivity detector (MIC4D) with high sensitivity, and we carry out a detailed theoretical investigation of the detector. In order to overcome the problem of a rising baseline level as a result of sensitivity improvements when using the multi-input detection method, we innovatively combine MIC4D with differential detection to propose a further-improved detector (DFMIC4D). The detector is composed of two channels, one for the reference and the other for the analyte. The signal output from differential amplification can effectively reduce the high baseline level and detection interference. In KCl solution with a concentration range of 10-4 to 10-5 M, the response to the solution is a linear function of the logarithm of the concentration, and this detector has a high slope. The slope of DFMIC4D is 1.393, higher than a traditional single-input capacitively coupled contactless conductivity detector (C4D: 0.905) and a double-input capacitively coupled contactless conductivity detector (DIC4D: 1.314). For 10-3 M KCl solution, the response-to-baseline ratio is 1.776 for C4D, 1.779 for DIC4D, and 12.06 for DFMIC4D, with a ratio increase of nearly 6-fold shown by our new detector. At a S/N (signal-to-noise) ratio of 3, the limit of detection (LOD) of DFMIC4D is low, reaching 0.7 nM. In addition, DFMIC4D can be applied to the detection of low-conductivity solutions and total dissolved solids (TDS) analysis. Compared with a standard conductivity meter, our detector shows better detection performance.
Collapse
Affiliation(s)
- Hongyu Nie
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Zhihui Li
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Xiaokun Wang
- College of Chemical Engineering, Sichuan University, Chengdu 610064, China.
| | - Rongmeng Gu
- College of Chemical Engineering, Sichuan University, Chengdu 610064, China.
| | - Hongyan Yuan
- College of Chemical Engineering, Sichuan University, Chengdu 610064, China.
| | - Yong Guo
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | - Dan Xiao
- College of Chemistry, Sichuan University, Chengdu 610064, China. .,College of Chemical Engineering, Sichuan University, Chengdu 610064, China.
| |
Collapse
|
7
|
Capillary and microchip electrophoresis with contactless conductivity detection for analysis of foodstuffs and beverages. Food Chem 2021; 375:131858. [PMID: 34923397 DOI: 10.1016/j.foodchem.2021.131858] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 11/29/2021] [Accepted: 12/10/2021] [Indexed: 12/17/2022]
Abstract
The paper provides a comprehensive survey of the use of capillary and microchip electrophoresis in combination with contactless conductivity detection (C4D) for the analysis of drinking water, beverages and foodstuffs. The introduction sets forth the fundamentals of conductivity detection anddescribes an axialC4Dversion. There is also a detailed discussion of the determination of inorganic ions, organic acids, fatty acids, amino acids, amines, carbohydrates, foreign substances and poisons from the standpoint of separation conditions, sample treatment and detection limits. Special attention is paid to the analysis of foodstuffs at microchips with emphasis on the employed material and connection of the microchip with the C4D. The review attempts to draw attention to modern trends, such as dual-opposite injection, field-enhanced sample injection, electromembrane extraction and on-line combination of microdialysis with CE. CE/C4D is characterised by high universality, high speed of analysis, simple sample preparation, small consumption of sample and other chemicals.
Collapse
|
8
|
UV-vis and electrical impedance characterizations of the hydroxychloroquine-zinc complex in the phospholipid-like oleic acid phase. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2021.115637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
9
|
Development of CE-C 4D Method for Determination Tropane Alkaloids. Molecules 2021; 26:molecules26195749. [PMID: 34641293 PMCID: PMC8510007 DOI: 10.3390/molecules26195749] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/15/2021] [Accepted: 09/20/2021] [Indexed: 11/22/2022] Open
Abstract
A fast method for the determination of tropane alkaloids, using a portable CE instrument with a capacitively coupled contactless conductivity detector (CE-C4D) was developed and validated for determination of atropine and scopolamine in seeds from Solanaceae family plants. Separation was obtained within 5 min, using an optimized background electrolyte consisting of 0.5 M acetic acid with 0.25% (w/v) β-CD. The limit of detection and quantification was 0.5 µg/mL and 1.5 µg/mL, respectively, for both atropine and scopolamine. The developed method was validated with the following parameters—precision (CV): 1.07–2.08%, accuracy of the assay (recovery, RE): 101.0–102.7% and matrix effect (ME): 92.99–94.23%. Moreover, the optimized CE-C4D method was applied to the analysis of plant extracts and pharmaceuticals, proving its applicability and accuracy.
Collapse
|
10
|
Investigation of the Effects of Electrode Geometry on the Performance of C 4D Sensor with Radial Configuration. SENSORS 2021; 21:s21134454. [PMID: 34209920 PMCID: PMC8272098 DOI: 10.3390/s21134454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/25/2021] [Accepted: 06/26/2021] [Indexed: 11/21/2022]
Abstract
Electrodes are basic components of C4D (capacitively coupled contactless conductivity detection) sensors, and different electrode structures (the configuration pattern or the electrode geometry) can lead to different measurement results. In this work, the effects of electrode geometry of radial configuration on the measurement performance of C4D sensors are investigated. Two geometrical parameters, the electrode length and the electrode angle, are considered. A FEM (finite element method) model based on the C4D method is developed. With the FEM model, corresponding simulation results of conductivity measurement with different electrode geometry are obtained. Meanwhile, practical experiments of conductivity measurement are also conducted. According to the simulation results and experimental results, the optimal electrode geometry of the C4D sensor with radial configuration is discussed and proposed. The recommended electrode length is 5–10 times of the pipe inner diameter and the recommended electrode angle is 120–160°.
Collapse
|
11
|
Takekawa VS, Marques LA, Strubinger E, Segato TP, Bogusz S, Brazaca LC, Carrilho E. Development of low-cost planar electrodes and microfluidic channels for applications in capacitively coupled contactless conductivity detection (C 4 D). Electrophoresis 2021; 42:1560-1569. [PMID: 34080201 DOI: 10.1002/elps.202000351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 05/27/2021] [Accepted: 05/28/2021] [Indexed: 01/11/2023]
Abstract
Electrochemical techniques are commonly applied to micro total analysis system (μTAS) devices mainly due to its high sensitivity and miniaturization capacity. Among many electrochemical techniques, capacitively coupled contactless conductivity detection (C4 D) stands out for not requiring direct electrode-solution contact, avoiding several problems such as electrolysis, bubble formation, and metal degradation. Furthermore, the instrumentation required for C4 D measurements is compact, low cost, and easy to use, allowing in situ measurements to be performed even by nonspecialized personal. Contrarily, the production of metallic electrodes and microchannels adequate for C4 D measurements commonly requires specialized facilities and workers, increasing the costs of applying these methods. We propose alternatives to batch manufacture metallic electrodes and polymeric microchannels for C4 D analysis using more straightforward equipment and lower-cost materials. Three devices with different dielectric layer compositions and electrode sizes were tested and compared regarding their analytical performance. The constructed platforms have shown a reduction of more than 64% in cost when compared to traditional techniques and displayed good linearity (R2 ≥ 0.994), reproducibility (RSD ≤ 4.07%, n = 3), and limits of detection (≤0.26 mmol/L) when measuring standard NaCl samples. Therefore, the proposed methods were successfully validated and are available for further C4 D applications such as diagnosis of dry-eye syndrome.
Collapse
Affiliation(s)
- Victor Sadanory Takekawa
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil.,Instituto Nacional de Ciência e Tecnologia de Bioanalítica-INCTBio, Campinas, São Paulo, Brazil
| | - Letícia Aparecida Marques
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil.,Instituto Nacional de Ciência e Tecnologia de Bioanalítica-INCTBio, Campinas, São Paulo, Brazil
| | - Ethan Strubinger
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil.,Instituto Nacional de Ciência e Tecnologia de Bioanalítica-INCTBio, Campinas, São Paulo, Brazil.,Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC
| | - Thiago Pinotti Segato
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil.,Instituto Nacional de Ciência e Tecnologia de Bioanalítica-INCTBio, Campinas, São Paulo, Brazil
| | - Stanislau Bogusz
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil
| | - Laís Canniatti Brazaca
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil.,Instituto Nacional de Ciência e Tecnologia de Bioanalítica-INCTBio, Campinas, São Paulo, Brazil
| | - Emanuel Carrilho
- Instituto de Química de São Carlos, Universidade de São Paulo, São Carlos, São Paulo, Brazil.,Instituto Nacional de Ciência e Tecnologia de Bioanalítica-INCTBio, Campinas, São Paulo, Brazil
| |
Collapse
|
12
|
Hata K, Nonaka N, Sato N, Kaneta T. Simultaneous separation of 17 anions by capillary electrophoresis with the addition of an organic solvent. Electrophoresis 2021; 42:1317-1322. [PMID: 33724495 DOI: 10.1002/elps.202100014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 03/09/2021] [Accepted: 03/10/2021] [Indexed: 11/06/2022]
Abstract
Seventeen inorganic and organic anions, that normally are insufficiently separated via ion chromatography, were completely separated by the addition of an organic solvent to a solution of BGE combined with an adjustment of the apparent pH via CE in combination with indirect UV absorbance detection. Methanol, ethanol, and acetonitrile were examined for their utility in manipulating the selective separation of anions. Methanol and acetonitrile were better modifiers than ethanol at enhancing the resolution of anions comigrating in an aqueous solution of BGE. Methanol was selected as the modifier that provided the largest separation window that could achieve a complete separation of the target analytes. Via the use of methanol, manipulation of the selectivity between inorganic anions and that between inorganic and organic anions was enhanced, but the separation between organic anions remained difficult when only methanol was used. By varying the apparent pH of the BGE in the presence of 10% v/v methanol, however, the separation selectivity between organic anions was substantially improved. Eventually, 7 inorganic and 10 organic anions were simultaneously separated using BGE at a pH of 6.3 in the presence of 10% v/v methanol.
Collapse
Affiliation(s)
- Kazuki Hata
- Inorganic Analysis Laboratories, Toray Research Center, Inc., Otsu, Shiga, Japan
| | - Noriko Nonaka
- Inorganic Analysis Laboratories, Toray Research Center, Inc., Otsu, Shiga, Japan
| | - Nobuyuki Sato
- Inorganic Analysis Laboratories, Toray Research Center, Inc., Otsu, Shiga, Japan
| | - Takashi Kaneta
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University, Okayama, Okayama, Japan
| |
Collapse
|
13
|
Zhao J, Xu Z. Capillary electrophoresis with dual C 4D/UV detection for simultaneously determining major metal cations and whey proteins in milk. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2021; 13:801-808. [PMID: 33496699 DOI: 10.1039/d0ay02092c] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A reliable and simple CE method with dual C4D and UV detection modes for simultaneous determination of major metal cations and whey proteins in milk samples was developed. Sample pretreatment comprised dilution, acidification to pH 4.55 with 10 mM AcOH and centrifugation. The complete separation of metal cations K+, Ca2+, Na+, and Mg2+ and whey proteins α-Lac, and β-Lg could be achieved respectively within 10 min and 20 min in a simple BGE composed of 1.0 M AcOH, 12 mM l-His and 2 mM 18-crown-6 with pH 2.74 at a voltage/current of +15 kV/12.5 μA. The samples were injected hydrodynamically by a pressure of 50 mbar for 5 s, the excitation voltage and excitation frequency of the C4D detector were 80 V and 1000 kHz, respectively and the detection wavelength of UV detection was set at 200 nm. In cation analysis, the range of the detection limit was 0.05-0.10 mg L-1 for C4D detection and 0.10-0.50 mg L-1 for UV detection, respectively, and the relative standard deviations (RSD%, n = 5) of intraday and interday analysis were 0.37-0.55% and 0.46-0.79% for the relative migration time, and 2.51-4.12% and 3.65-4.91% for the peak area, respectively. In whey protein analysis, the detection limits of β-Lg and α-Lac analysis were 5 mg L-1 and 3 mg L-1, respectively and the relative standard deviations (RSD%, n = 5) of intraday and interday analysis were 0.29-0.31% and 0.43-0.48% for the migration time and 2.89-3.25% and 3.29-4.18% for the peak area, respectively. The content of four major metal cations and two whey proteins in various types of milk samples was obtained. The results indicated that the content of metal cations varied little in milk samples of different brands and prices, while the content of whey proteins, as thermosensitive active proteins, varied greatly among different heat-treated milk samples.
Collapse
Affiliation(s)
- Jing Zhao
- College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620, China.
| | | |
Collapse
|
14
|
Huang W. Open tubular ion chromatography: A state-of-the-Art review. Anal Chim Acta 2021; 1143:210-224. [PMID: 33384120 DOI: 10.1016/j.aca.2020.08.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 08/04/2020] [Accepted: 08/06/2020] [Indexed: 11/19/2022]
Abstract
This review summarizes the progress in open tubular ion chromatography (OTIC) over the period from 1981 to 2020. Although OTIC columns provide superior column efficiency, require very little sample volumes, and consume a minimum level of eluents compared to regular packed columns, not many reports can be found from the literature mainly due to the difficulties in the preparation of OTIC columns and the harsh system requirements, such as pL-nL injections and extremely small detection volumes. However, technical advances, e.g., capacitively coupled contactless conductivity detectors (C4Ds), hydroxide eluent compatible polymer-based OTIC columns, electrodialytic capillary suppressors, and nanovolume gas-free hydroxide eluent generators (EGs), have removed the obstacles to OTIC. As such, in this review, the author focused on the development of the key components in an OTIC system from the perspective of instrument development. A brief revisit of open tubular (OT) column theory is first presented, followed by a discussion of the system configuration and component development. Attention is given to the advances in the development of the suppressed open tubular ion chromatography (SOTIC) system.
Collapse
Affiliation(s)
- Weixiong Huang
- School of Environmental Studies, China University of Geosciences, Wuhan, 430078, Hubei, China.
| |
Collapse
|
15
|
Amorim TL, Duarte LM, da Silva EM, de Oliveira MAL. Capillary electromigration methods for fatty acids determination in vegetable and marine oils: A review. Electrophoresis 2020; 42:289-304. [PMID: 33169855 DOI: 10.1002/elps.202000260] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 10/23/2020] [Accepted: 11/05/2020] [Indexed: 11/12/2022]
Abstract
Fatty acids determination is of paramount importance for quality control and suitable labeling of edible oils, required by regulatory agencies in several countries, and fast methods for this determination are worldly desired. This review article aimed to explore the available analytical methods for vegetable and marine oils analyses employing CE, which can be a straightforward and faster alternative than GC methods for fatty acid determination, considering some purposes. CE usually offers the possibility of a rapid analysis with a simple preparation of the sample, without requiring specific columns, which are inherent advantages of the technique. Instrumental conditions and the key points about fatty acids determination employing the technique are highlighted, and the main challenges and perspectives are also approached. Potential use of CE for edible oil analyses has been demonstrated for research and routine, which can be of interest for industries, regulatory agencies, and edible oil researchers. Therefore, we have explored the analytical approaches described in the last decades, intending to spread the interest of CE methods for fatty acid monitoring, label accuracy assessment, and food authenticity evaluation of edible oils.
Collapse
Affiliation(s)
- Tatiane Lima Amorim
- Grupo de Química Analítica e Quimiometria (GQAQ), Departamento de Química, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Lucas Mattos Duarte
- Departamento de Química Analítica, Instituto de Química, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Erick Mendes da Silva
- Grupo de Química Analítica e Quimiometria (GQAQ), Departamento de Química, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| | - Marcone Augusto Leal de Oliveira
- Grupo de Química Analítica e Quimiometria (GQAQ), Departamento de Química, Universidade Federal de Juiz de Fora, Juiz de Fora, MG, Brazil
| |
Collapse
|
16
|
Amorim TL, de Oliveira MAL. Advances in Lipid Capillary Electromigration Methods to Food Analysis Within the 2010s Decade. FOOD ANAL METHOD 2020. [DOI: 10.1007/s12161-020-01772-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
17
|
Jones J, Ha NS, Barajas AG, Chatziioannou AF, van Dam RM. Integration of High-Resolution Radiation Detector for Hybrid Microchip Electrophoresis. Anal Chem 2020; 92:3483-3491. [PMID: 31986878 PMCID: PMC7410349 DOI: 10.1021/acs.analchem.9b04827] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
For decades, there has been immense progress in miniaturizing analytical methods based on electrophoresis to improve sensitivity and to reduce sample volumes, separation times, and/or equipment cost and space requirements, in applications ranging from analysis of biological samples to environmental analysis to forensics. In the field of radiochemistry, where radiation-shielded laboratory space is limited, there has been great interest in harnessing the compactness, high efficiency, and speed of microfluidics to synthesize short-lived radiolabeled compounds. We recently proposed that analysis of these compounds could also benefit from miniaturization and have been investigating capillary electrophoresis (CE) and hybrid microchip electrophoresis (hybrid-MCE) as alternatives to the typically used high-performance liquid chromatography (HPLC). We previously showed separation of the positron-emission tomography (PET) imaging tracer 3'-deoxy-3'-fluorothymidine (FLT) from its impurities in a hybrid-MCE device with UV detection, with similar separation performance to HPLC, but with improved speed and lower sample volumes. In this paper, we have developed an integrated radiation detector to enable measurement of the emitted radiation from radiolabeled compounds. Though conventional radiation detectors have been incorporated into CE systems in the past, these approaches cannot be readily integrated into a compact hybrid-MCE device. We instead employed a solid-state avalanche photodiode (APD)-based detector for real-time, high-sensitivity β particle detection. The integrated system can reliably separate [18F]FLT from its impurities and perform chemical identification via coinjection with nonradioactive reference standard. This system can quantitate samples with radioactivity concentrations as low as 114 MBq/mL (3.1 mCi/mL), which is sufficient for analysis of radiochemical purity of radiopharmaceuticals.
Collapse
Affiliation(s)
- Jason Jones
- Crump Institute for Molecular Imaging and Department of
Molecular and Medical Pharmacology, David Geffen School of Medicine, University of
California Los Angeles, Los Angeles, CA 90095, USA
- Physics & Biology in Medicine Interdepartmental
Graduate Program, David Geffen School of Medicine, University of California Los
Angeles, Los Angeles, CA 90095, USA
| | - Noel S. Ha
- Crump Institute for Molecular Imaging and Department of
Molecular and Medical Pharmacology, David Geffen School of Medicine, University of
California Los Angeles, Los Angeles, CA 90095, USA
- Department of Bioengineering, Henry Samueli School of
Engineering and Applied Science, University of California Los Angeles, Los Angeles,
CA 90095, USA
| | - Alec G. Barajas
- Crump Institute for Molecular Imaging and Department of
Molecular and Medical Pharmacology, David Geffen School of Medicine, University of
California Los Angeles, Los Angeles, CA 90095, USA
- Department of Chemistry & Biochemistry, University of
California Los Angeles, Los Angeles, CA 90095, USA
| | - Arion F. Chatziioannou
- Crump Institute for Molecular Imaging and Department of
Molecular and Medical Pharmacology, David Geffen School of Medicine, University of
California Los Angeles, Los Angeles, CA 90095, USA
- Physics & Biology in Medicine Interdepartmental
Graduate Program, David Geffen School of Medicine, University of California Los
Angeles, Los Angeles, CA 90095, USA
- Department of Molecular & Medical Pharmacology,
University of California Los Angeles, Los Angeles, CA 90095, USA
| | - R. Michael van Dam
- Crump Institute for Molecular Imaging and Department of
Molecular and Medical Pharmacology, David Geffen School of Medicine, University of
California Los Angeles, Los Angeles, CA 90095, USA
- Physics & Biology in Medicine Interdepartmental
Graduate Program, David Geffen School of Medicine, University of California Los
Angeles, Los Angeles, CA 90095, USA
- Department of Bioengineering, Henry Samueli School of
Engineering and Applied Science, University of California Los Angeles, Los Angeles,
CA 90095, USA
- Department of Molecular & Medical Pharmacology,
University of California Los Angeles, Los Angeles, CA 90095, USA
| |
Collapse
|
18
|
Wu Y, Lu B, Zhang W, Jiang Y, Wang B, Huang Z. A New Logging-While-Drilling Method for Resistivity Measurement in Oil-Based Mud. SENSORS 2020; 20:s20041075. [PMID: 32079132 PMCID: PMC7070431 DOI: 10.3390/s20041075] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 02/05/2020] [Accepted: 02/11/2020] [Indexed: 11/16/2022]
Abstract
Resistivity logging is an important technique for identifying and estimating reservoirs. Oil-based mud (OBM) can improve drilling efficiency and decrease operation risks, and has been widely used in the well logging field. However, the non-conductive OBM makes the traditional logging-while-drilling (LWD) method with low frequency ineffective. In this work, a new oil-based LWD method is proposed by combining the capacitively coupled contactless conductivity detection (C4D) technique and the inductive coupling principle. The C4D technique is to overcome the electrical insulation problem of the OBM and construct an effective alternating current (AC) measurement path. Based on the inductive coupling principle, an induced voltage can be formed to be the indirect excitation voltage of the AC measurement path. Based on the proposed method, a corresponding logging instrument is developed. Numerical simulation was carried out and results show that the logging instrument has good measurement accuracy, deep detection depth and high vertical resolution. Practical experiments were also carried out, including the resistance box experiment and the well logging experiment. The results of the resistance box experiment show that the logging instrument has good resistance measurement accuracy. Lastly, the results of the well logging experiment indicate that the logging instrument can accurately reflect the positions of different patterns on the wellbore of the experimental well. Both numerical simulation and practical experiments verify the feasibility and effectiveness of the new method.
Collapse
Affiliation(s)
- Yongkang Wu
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, China; (Y.W.); (Y.J.); (Z.H.)
| | - Baoping Lu
- Sinopec Research Institute of Petroleum Engineering, Beijing 100101, China; (B.L.); (W.Z.)
| | - Wei Zhang
- Sinopec Research Institute of Petroleum Engineering, Beijing 100101, China; (B.L.); (W.Z.)
- State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development, Beijing 100101, China
| | - Yandan Jiang
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, China; (Y.W.); (Y.J.); (Z.H.)
| | - Baoliang Wang
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, China; (Y.W.); (Y.J.); (Z.H.)
- Correspondence:
| | - Zhiyao Huang
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, China; (Y.W.); (Y.J.); (Z.H.)
| |
Collapse
|
19
|
Measuring venous-arterial differences of valine, isoleucine, leucine, alanine and glutamine in skeletal muscles using counter-current electrophoresis with contactless conductivity detection. J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2019.113772] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
20
|
Huang X, Xiao D, Tong Y, Chen Z. A sensitive photochemical reaction-capacitively coupled contactless conductivity detection system for HPLC and its application in determination of Cyclosporin A. Talanta 2020; 206:120242. [DOI: 10.1016/j.talanta.2019.120242] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 08/05/2019] [Accepted: 08/07/2019] [Indexed: 01/23/2023]
|
21
|
Zhu HT, Chen Y, Xiong YF, Xu F, Lu YQ. A Flexible Wireless Dielectric Sensor for Noninvasive Fluid Monitoring. SENSORS 2019; 20:s20010174. [PMID: 31892240 PMCID: PMC6982699 DOI: 10.3390/s20010174] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 12/17/2019] [Accepted: 12/26/2019] [Indexed: 01/28/2023]
Abstract
A flexible wireless dielectric sensor is presented here for noninvasively monitoring the permittivity and conductivity of fluids, based on resistor–inductor–capacitor (RLC) resonant circuit and capacitively coupled contactless conductivity detection (C4D) technique. The RLC sensor consists of one single-turn inductor and one interdigital capacitor. The resonant frequency of the device is sensitive to the surrounding environment, thanks to the electric field leaked out between the interdigital capacitor electrodes. Through the high-frequency structure simulator (HFSS) simulation, and experiments on ethanol/water solutions and NaCl solutions, it was confirmed that a fluid’s permittivity and conductivity could be detected by the return loss curve (S11). With great repeatability and stability, the proposed sensor has potential for broad applications, especially in wearable low-cost smart devices.
Collapse
|
22
|
Chaneam S, Kaewyai K, Mantim T, Chaisuksant R, Wilairat P, Nacapricha D. Simultaneous and direct determination of urea and creatinine in human urine using a cost-effective flow injection system equipped with in-house contactless conductivity detector and LED colorimeter. Anal Chim Acta 2019; 1073:54-61. [DOI: 10.1016/j.aca.2019.05.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 04/17/2019] [Accepted: 05/02/2019] [Indexed: 12/15/2022]
|
23
|
Yang S, Li Y, Li F, Yang Z, Quan F, Zhou L, Pu Q. Thiol-ene Click Derivatization for the Determination of Acrylamide in Potato Products by Capillary Electrophoresis with Capacitively Coupled Contactless Conductivity Detection. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:8053-8060. [PMID: 31276393 DOI: 10.1021/acs.jafc.9b01525] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The development of analytical methods for acrylamide formed during food processing is of great significance for food safety, but limited by its inherent characteristics, the analysis of acrylamide is a continuing challenge. In this study, an efficient derivatization strategy for acrylamide based on thiol-ene click reaction with cysteine as derivatization reagent was proposed, and the resulting derivative was then analyzed by capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D). After systematic investigation including catalyst dosage (0-20 mM), reaction temperature (30-90 °C) and time (1-60 min), and cysteine concentration (0.2-3.6 mM), acrylamide could be efficiently labeled by 2.0 mM cysteine at 70 °C for 10 min using 4 mM n-butylamine as catalyst. Application of 10 mM triethylamine as separation buffer, the labeled acrylamide was analyzed within 2.0 min, and the relative standard deviations of migration time and peak area were less than 0.84% and 5.6%, indicating good precision. The C4D signal of acrylamide derivative showed a good linear relationship with acrylamide concentration in the range of 7-200 μM with the correlation coefficient of 0.9991. The limit of detection and limit of quantification were calculated to be 0.16 μM and 0.52 μM, respectively. Assisted further by the QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample pretreatment, the developed derivatization strategy and subsequent CE-C4D method were successfully applied for the determination of acrylamide in potato products.
Collapse
Affiliation(s)
- Shuping Yang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Yuting Li
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Fan Li
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Zhenyu Yang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Feifei Quan
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Lei Zhou
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| | - Qiaosheng Pu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering , Lanzhou University , Lanzhou 730000 , China
| |
Collapse
|
24
|
Selective capillary electrophoresis separation of mono and divalent cations within a high-surface area-to-volume ratio multi-lumen capillary. Anal Chim Acta 2019; 1051:41-48. [DOI: 10.1016/j.aca.2018.11.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 11/14/2018] [Accepted: 11/15/2018] [Indexed: 12/16/2022]
|
25
|
He Y, Ye X, Ji H, Huang Z, Wang B, Li H. A new method for online monitoring of boiling process in mini-channels. AIChE J 2019. [DOI: 10.1002/aic.16528] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Yuchen He
- State Key Laboratory of Industrial Control Technology; College of Control Science and Engineering, Zhejiang University; Hangzhou, 310027 P.R. China
| | - Xin Ye
- State Key Laboratory of Industrial Control Technology; College of Control Science and Engineering, Zhejiang University; Hangzhou, 310027 P.R. China
| | - Haifeng Ji
- State Key Laboratory of Industrial Control Technology; College of Control Science and Engineering, Zhejiang University; Hangzhou, 310027 P.R. China
| | - Zhiyao Huang
- State Key Laboratory of Industrial Control Technology; College of Control Science and Engineering, Zhejiang University; Hangzhou, 310027 P.R. China
| | - Baoliang Wang
- State Key Laboratory of Industrial Control Technology; College of Control Science and Engineering, Zhejiang University; Hangzhou, 310027 P.R. China
| | - Haiqing Li
- State Key Laboratory of Industrial Control Technology; College of Control Science and Engineering, Zhejiang University; Hangzhou, 310027 P.R. China
| |
Collapse
|
26
|
Tůma P, Sommerová B, Šiklová M. Monitoring of adipose tissue metabolism using microdialysis and capillary electrophoresis with contactless conductivity detection. Talanta 2019; 192:380-386. [DOI: 10.1016/j.talanta.2018.09.076] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Revised: 09/19/2018] [Accepted: 09/20/2018] [Indexed: 02/02/2023]
|
27
|
Lam SC, Sanz Rodriguez E, Haddad PR, Paull B. Recent advances in open tubular capillary liquid chromatography. Analyst 2019; 144:3464-3482. [DOI: 10.1039/c9an00329k] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This review covers advances and applications of open tubular capillary liquid chromatography (OT-LC) over the period 2007–2018.
Collapse
Affiliation(s)
- Shing Chung Lam
- ASTech
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech)
- and Australian Centre for Research on Separation Science (ACROSS)
- School of Natural Sciences
- University of Tasmania
| | - Estrella Sanz Rodriguez
- ASTech
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech)
- and Australian Centre for Research on Separation Science (ACROSS)
- School of Natural Sciences
- University of Tasmania
| | - Paul R. Haddad
- ASTech
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech)
- and Australian Centre for Research on Separation Science (ACROSS)
- School of Natural Sciences
- University of Tasmania
| | - Brett Paull
- ASTech
- ARC Training Centre for Portable Analytical Separation Technologies (ASTech)
- and Australian Centre for Research on Separation Science (ACROSS)
- School of Natural Sciences
- University of Tasmania
| |
Collapse
|
28
|
20th anniversary of axial capacitively coupled contactless conductivity detection in capillary electrophoresis. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2018.03.007] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
29
|
Beutner A, Scherer B, Matysik FM. Dual detection for non-aqueous capillary electrophoresis combining contactless conductivity detection and mass spectrometry. Talanta 2018; 183:33-38. [PMID: 29567184 DOI: 10.1016/j.talanta.2018.02.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 02/01/2018] [Accepted: 02/04/2018] [Indexed: 11/28/2022]
Abstract
Coupling of two detectors is a powerful tool to enhance the overall analytical performance generating complementary information and overcoming the limitations of the single detectors. In this work, capacitively coupled contactless conductivity detection (C4D) and electrospray ionization mass spectrometry (ESI-MS) were coupled in conjunction with non-aqueous capillary electrophoresis (NACE). Non-aqueous electrolytes are highly compatible with ESI due to their volatility. Moreover, they exhibit low background conductivity, which is essential for the detection with C4D. A NACE-C4D-MS method was developed using an acetonitrile buffer containing 2 M HAc and 4 mM NH4Ac as background electrolyte. The influence of the inner diameter of the separation capillary on the C4D was studied and taken into account. A capillary with 50 µm inner diameter was found to be best suited. The complementarity of the two detectors was shown by determining a sample mixture containing choline, thiamine, nitrate, and chloride as well as bromide and acetylcholine as internal standards. The C4D was the detector of choice for the inorganic ions, which were not detectable with the MS whereas the MS had much lower limits of detections for the organic biomolecules. The method was applied on an extract of a food supplement containing the model analytes.
Collapse
Affiliation(s)
- Andrea Beutner
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany
| | - Beate Scherer
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitaetsstrasse 31, 93053 Regensburg, Germany.
| |
Collapse
|
30
|
Nakatani N, Mosqueda A, Cabot JM, Rodriguez ES, Yoshikawa K, Paull B. Rapid screening of inorganic and organic anions in liquid by-products from hydrothermal treatment of biomass by capillary electrophoresis. Electrophoresis 2018; 39:1014-1020. [DOI: 10.1002/elps.201700366] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 12/13/2017] [Accepted: 12/13/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Nobutake Nakatani
- Department of Environmental and Symbiotic Science; College of Agriculture; Food and Environment Sciences; Rakuno Gakuen University; Ebetsu Hokkaido Japan
- Australian Centre for Research on Separation Science; School of Physical Sciences; University of Tasmania; Hobart Tasmania Australia
| | - Alexander Mosqueda
- Department of Transdisciplinary Science and Engineering; Tokyo Institute of Technology; Yokohama Kanagawa Japan
| | - Joan Marc Cabot
- Australian Centre for Research on Separation Science; School of Physical Sciences; University of Tasmania; Hobart Tasmania Australia
- ARC Centre of Excellence for Electromaterials Science; School of Physical Sciences; University of Tasmania; Hobart Tasmania Australia
| | - Estrella Sanz Rodriguez
- Australian Centre for Research on Separation Science; School of Physical Sciences; University of Tasmania; Hobart Tasmania Australia
| | - Kunio Yoshikawa
- Department of Transdisciplinary Science and Engineering; Tokyo Institute of Technology; Yokohama Kanagawa Japan
| | - Brett Paull
- Australian Centre for Research on Separation Science; School of Physical Sciences; University of Tasmania; Hobart Tasmania Australia
- ARC Centre of Excellence for Electromaterials Science; School of Physical Sciences; University of Tasmania; Hobart Tasmania Australia
| |
Collapse
|
31
|
Ha NS, Sadeghi S, van Dam RM. Recent Progress toward Microfluidic Quality Control Testing of Radiopharmaceuticals. MICROMACHINES 2017; 8:E337. [PMID: 30400527 PMCID: PMC6190332 DOI: 10.3390/mi8110337] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 11/08/2017] [Accepted: 11/18/2017] [Indexed: 01/18/2023]
Abstract
Radiopharmaceuticals labeled with short-lived positron-emitting or gamma-emitting isotopes are injected into patients just prior to performing positron emission tomography (PET) or single photon emission tomography (SPECT) scans, respectively. These imaging modalities are widely used in clinical care, as well as in the development and evaluation of new therapies in clinical research. Prior to injection, these radiopharmaceuticals (tracers) must undergo quality control (QC) testing to ensure product purity, identity, and safety for human use. Quality tests can be broadly categorized as (i) pharmaceutical tests, needed to ensure molecular identity, physiological compatibility and that no microbiological, pyrogenic, chemical, or particulate contamination is present in the final preparation; and (ii) radioactive tests, needed to ensure proper dosing and that there are no radiochemical and radionuclidic impurities that could interfere with the biodistribution or imaging. Performing the required QC tests is cumbersome and time-consuming, and requires an array of expensive analytical chemistry equipment and significant dedicated lab space. Calibrations, day of use tests, and documentation create an additional burden. Furthermore, in contrast to ordinary pharmaceuticals, each batch of short-lived radiopharmaceuticals must be manufactured and tested within a short period of time to avoid significant losses due to radioactive decay. To meet these challenges, several efforts are underway to develop integrated QC testing instruments that automatically perform and document all of the required tests. More recently, microfluidic quality control systems have been gaining increasing attention due to vastly reduced sample and reagent consumption, shorter analysis times, higher detection sensitivity, increased multiplexing, and reduced instrumentation size. In this review, we describe each of the required QC tests and conventional testing methods, followed by a discussion of efforts to directly miniaturize the test or examples in the literature that could be implemented for miniaturized QC testing.
Collapse
Affiliation(s)
- Noel S Ha
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Science, University of California Los Angeles, Los Angeles, CA 90095, USA.
- Crump Institute for Molecular Imaging and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA.
| | - Saman Sadeghi
- Crump Institute for Molecular Imaging and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA.
| | - R Michael van Dam
- Department of Bioengineering, Henry Samueli School of Engineering and Applied Science, University of California Los Angeles, Los Angeles, CA 90095, USA.
- Crump Institute for Molecular Imaging and Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA.
| |
Collapse
|
32
|
Affiliation(s)
- Xilong Yuan
- Department of Chemistry, Queen's University , Kingston, Ontario K7L 3N6, Canada
| | - Richard D Oleschuk
- Department of Chemistry, Queen's University , Kingston, Ontario K7L 3N6, Canada
| |
Collapse
|
33
|
Wang YX, Ji HF, Huang ZY, Wang BL, Li HQ. Online measurement of conductivity/permittivity of fluid by a new contactless impedance sensor. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:055111. [PMID: 28571398 DOI: 10.1063/1.4983208] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
By expanding the contactless conductivity detection (CCD) technique to contactless impedance detection technique, a new contactless impedance sensor is designed to implement the online measurement for both the conductivity of a conductive fluid and the permittivity of a non-conductive fluid. In the new contactless impedance sensor, a new simulated inductor is developed to overcome the unfavorable influences of the coupling capacitances by impedance elimination principle, and the digital phase-sensitive demodulation (DPSD) technique is adopted to realize the impedance measurement. To verify the effectiveness of the new contactless impedance sensor, simulation experiments (using different resistors, capacitors, and their combinations) and practical fluid experiments (using KCl solutions with different concentrations, eight organic solvents, and pure water) are carried out. The experimental results show that the development of the new contactless impedance sensor is successful and the conductivity/permittivity measurement performance of the new sensor is satisfactory. The maximum relative error of conductivity measurement is 3.1% and the maximum relative error of permittivity measurement is 5.5%. Compared with the conventional conductivity/permittivity sensors, the new sensor can implement the contactless online measurement of both the two electrical parameters of fluid. Meanwhile, the new contactless impedance sensor is suitable for industrial applications and has the advantages of simple construction and low cost.
Collapse
Affiliation(s)
- Y X Wang
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - H F Ji
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Z Y Huang
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - B L Wang
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - H Q Li
- State Key Laboratory of Industrial Control Technology, College of Control Science and Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China
| |
Collapse
|
34
|
Elbashir AA, Schmitz OJ, Aboul-Enein HY. Application of capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4
D): An update. Biomed Chromatogr 2017; 31. [DOI: 10.1002/bmc.3945] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 01/20/2017] [Accepted: 02/03/2017] [Indexed: 12/29/2022]
Affiliation(s)
- Abdalla A. Elbashir
- Faculty of Science, Chemistry Department; University of Khartoum; Khartoum Sudan
- Applied Analytical Chemistry, Faculty of Chemistry; University of Duisburg-Essen; Essen Germany
| | - Oliver J. Schmitz
- Applied Analytical Chemistry, Faculty of Chemistry; University of Duisburg-Essen; Essen Germany
| | - Hassan Y. Aboul-Enein
- Pharmaceutical and Medicinal Chemistry Department, Pharmaceutical and Drug Industries Research Division; National Research Centre; Giza Egypt
| |
Collapse
|
35
|
Analysis and characterization of aluminum chlorohydrate oligocations by capillary electrophoresis. J Chromatogr A 2017; 1492:144-150. [PMID: 28284762 DOI: 10.1016/j.chroma.2017.02.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 02/02/2017] [Accepted: 02/05/2017] [Indexed: 11/23/2022]
Abstract
Aluminum chlorohydrates (ACH) are the active ingredients used in most antiperspirant products. ACH is a water soluble aluminum complex which contains several oligomeric polycations of aluminum with degrees of polymerization up to Al13 or Al30. The characterization and quantification of ACH oligo-cations remain a challenging issue of primary interest for developing structure/antiperspirant activity correlations, and for controlling the ACH ingredients. In this work, highly repeatable capillary electrophoresis (CE) separation of Al3+, Al13 and Al30 oligomers contained in ACH samples was obtained at pH 4.8, owing to a careful choice of the background electrolyte counter-ion and chromophore, capillary I.D. and capillary coating. This is the first reported separation of Al13 and Al30 oligomers in conditions that are compatible with the aluminum speciation in ACH solution or in conditions of antiperspirant application/formulation. Al13 and Al30 effective charge numbers were also determined from the sensitivity of detection in indirect UV detection mode. The relative mass proportion of Al13 compared to Al13+Al30 could be determined in different aluminum chlorohydrate samples. Due to its simplicity, repeatability/reproducibility, minimal sample preparation and mild analytical conditions, CE appears to be a promising analytical separation technique for the characterization of ACH materials and for the study of structure/antiperspirant activity correlations.
Collapse
|
36
|
Sustained drug release and electrochemical performance of ethyl cellulose-magnesium hydrogen phosphate composite. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 71:735-743. [DOI: 10.1016/j.msec.2016.10.062] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 09/28/2016] [Accepted: 10/24/2016] [Indexed: 12/20/2022]
|
37
|
Tůma P. Frequency-tuned contactless conductivity detector for the electrophoretic separation of clinical samples in capillaries with very small internal dimensions. J Sep Sci 2017; 40:940-947. [PMID: 27995764 DOI: 10.1002/jssc.201601213] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 11/19/2016] [Accepted: 11/28/2016] [Indexed: 12/27/2022]
Abstract
An axial design of a capacitively coupled contactless conductivity detector was tested in combination with fused-silica capillaries with internal diameters of 10, 15, and 25 μm, which are used for high-efficiency electrophoretic separation. The transmission of the signal in the detection probe dependent on the specific conductivity of the solution in the capillary in the range 0-278 mS.m-1 has a complex character and a minimum appears on the curve at very low conductivities. The position of the minimum of the calibration dependence gradually shifts with decreasing frequency of the exciting signal from 1.0 to 0.25 MHz toward lower specific conductivity values. The presence of a minimum on the calibration curves is a natural property of the axial design of contactless conductivity detector, demonstrated by solution of the equivalent electrical circuit of the detection probe, and is specifically caused by the use of shielding foil. The behavior of contactless conductivity detector in the vicinity of the minimum was documented for practical separations of amino acids in solutions of 3.2 M acetic acid with addition of 0-50% v/v methanol.
Collapse
Affiliation(s)
- Petr Tůma
- Department of Biochemistry, Cell and Molecular Biology, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| |
Collapse
|
38
|
The use of polarity switching for the sensitive determination of nitrate in human cerebrospinal fluid by capillary electrophoresis with contactless conductivity detection. J Chromatogr A 2016; 1447:148-54. [DOI: 10.1016/j.chroma.2016.04.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Revised: 04/05/2016] [Accepted: 04/14/2016] [Indexed: 01/04/2023]
|
39
|
Beutner A, Cunha RR, Richter EM, Matysik FM. Combining C4
D and MS as a dual detection approach for capillary electrophoresis. Electrophoresis 2016; 37:931-5. [DOI: 10.1002/elps.201500512] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Revised: 12/23/2015] [Accepted: 12/23/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Andrea Beutner
- Institute for Analytical Chemistry, Chemo- and Biosensors; Regensburg Germany
| | | | | | | |
Collapse
|
40
|
New C4D Sensor with a Simulated Inductor. SENSORS 2016; 16:165. [PMID: 26828493 PMCID: PMC4801543 DOI: 10.3390/s16020165] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 01/09/2016] [Accepted: 01/22/2016] [Indexed: 11/16/2022]
Abstract
A new capacitively coupled contactless conductivity detection (C4D) sensor with an improved simulated inductor is developed in this work. The improved simulated inductor is designed on the basis of the Riordan-type floating simulated inductor. With the improved simulated inductor, the negative influence of the coupling capacitances is overcome and the conductivity measurement is implemented by the series resonance principle. The conductivity measurement experiments are carried out in three pipes with different inner diameters of 3.0 mm, 4.6 mm and 6.4 mm, respectively. The experimental results show that the designs of the new C4D sensor and the improved simulated inductor are successful. The maximum relative error of the conductivity measurement is less than 5%. Compared with the C4D sensors using practical inductors, the measurement accuracy of the new C4D sensor is comparable. The research results also indicate that the adjustability of a simulated inductor can reduce the requirement for the AC source and guarantee the interchangeableness. Meanwhile, it is recommended that making the potential of one terminal of a simulated inductor stable is beneficial to the running stability. Furthermore, this work indirectly verifies the possibility and feasibility of the miniaturization of the C4D sensor by using the simulated inductor technique and lays a good foundation for future research work.
Collapse
|
41
|
Duong HA, Le MD, Nguyen KDM, Hauser PC, Pham HV, Mai TD. In-house-made capillary electrophoresis instruments coupled with contactless conductivity detection as a simple and inexpensive solution for water analysis: a case study in Vietnam. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2015; 17:1941-1951. [PMID: 26452107 DOI: 10.1039/c5em00362h] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A simple and inexpensive method for the determination of various ionic species in different water matrices is discussed in this study. The approach is based on the employment of in-house-made capillary electrophoresis (CE) instruments with capacitively coupled contactless conductivity detection (C(4)D), which can be realized even when only a modest financial budget and limited expertise are available. Advantageous features and considerations of these instruments are detailed following their pilot deployment in Vietnam. Different categories of ionic species, namely major inorganic cations (K(+), Na(+), Ca(2+), Mg(2+), and NH4(+)) and major inorganic anions (Cl(-), NO3(-), NO2(-), SO4(2-), and phosphate), in different water matrices in Vietnam were determined using these in-house fabricated instruments. Inorganic trivalent arsenic (As(iii)), which is the most abundant form of arsenic in reducing groundwater, was determined by CE-C(4)D. The effect of some interfering ions in groundwater on the analytical performance was investigated and is highlighted. The results from in-house-made CE-C(4)D-instruments were cross-checked with those obtained using the standard methods (AAS, AES, UV and IC), with correlation coefficients r(2) ≥ 0.9 and deviations from the referenced results less than 15%.
Collapse
Affiliation(s)
- Hong Anh Duong
- Centre for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, Nguyen Trai Street 334, Hanoi, Vietnam.
| | - Minh Duc Le
- Centre for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, Nguyen Trai Street 334, Hanoi, Vietnam.
| | - Kim Diem Mai Nguyen
- Centre for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, Nguyen Trai Street 334, Hanoi, Vietnam.
| | - Peter C Hauser
- University of Basel, Department of Chemistry, Spitalstrasse 51, 4056 Basel, Switzerland
| | - Hung Viet Pham
- Centre for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, Nguyen Trai Street 334, Hanoi, Vietnam.
| | - Thanh Duc Mai
- Centre for Environmental Technology and Sustainable Development (CETASD), Hanoi University of Science, Nguyen Trai Street 334, Hanoi, Vietnam.
| |
Collapse
|
42
|
Recent applications of microchip electrophoresis to biomedical analysis. J Pharm Biomed Anal 2015; 113:72-96. [DOI: 10.1016/j.jpba.2015.03.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 02/28/2015] [Accepted: 03/03/2015] [Indexed: 11/22/2022]
|
43
|
Exploring the possibilities of capacitively coupled contactless conductivity detection in combination with liquid chromatography for the analysis of polar compounds using aminoglycosides as test case. J Pharm Biomed Anal 2015; 112:155-68. [DOI: 10.1016/j.jpba.2014.12.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/01/2014] [Accepted: 12/05/2014] [Indexed: 11/24/2022]
|
44
|
Duarte Junior GF, Fracassi da Silva JA, Mendonça Francisco KJ, do Lago CL, Carrilho E, Coltro WKT. Metalless electrodes for capacitively coupled contactless conductivity detection on electrophoresis microchips. Electrophoresis 2015; 36:1935-40. [DOI: 10.1002/elps.201500033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 03/05/2015] [Accepted: 03/13/2015] [Indexed: 01/17/2023]
Affiliation(s)
| | - José Alberto Fracassi da Silva
- Instituto de Química; Universidade Estadual de Campinas; Campinas São Paulo Brasil
- Instituto Nacional de Ciência e Tecnologia de Bioanalítica; Campinas São Paulo Brasil
| | | | | | - Emanuel Carrilho
- Instituto de Química de São Carlos; Universidade de São Paulo; São Carlos São Paulo Brasil
- Instituto Nacional de Ciência e Tecnologia de Bioanalítica; Campinas São Paulo Brasil
| | - Wendell K. T. Coltro
- Instituto de Química; Universidade Federal de Goiás; Goiânia Goiás Brasil
- Instituto Nacional de Ciência e Tecnologia de Bioanalítica; Campinas São Paulo Brasil
| |
Collapse
|
45
|
Kwon H, Jiang W, Kool ET. Pattern-Based Detection of Anion Pollutants in Water with DNA Polyfluorophores. Chem Sci 2015; 6:2575-2583. [PMID: 26146537 PMCID: PMC4486361 DOI: 10.1039/c4sc03992k] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 02/18/2015] [Indexed: 12/18/2022] Open
Abstract
Many existing irrigation, industrial and chemical storage sites are currently introducing hazardous anions into groundwater, making the monitoring of such sites a high priority. Detecting and quantifying anions in water samples typically requires complex instrumentation, adding cost and delaying analysis. Here we address these challenges by development of an optical molecular method to detect and discriminate a broad range of anionic contaminants with DNA-based fluorescent sensors. A library of 1296 tetrameric-length oligodeoxyfluorosides (ODFs) composed of metal ligand and fluorescence modulating monomers was constructed with a DNA synthesizer on PEG-polystyrene microbeads. These oligomers on beads were incubated with YIII or ZnII ions to provide affinity and responsiveness to anions. Seventeen anions were screened with the library under an epifluorescence microscope, ultimately yielding eight chemosensors that could discriminate 250 μM solutions of all 17 anions in buffered water using their patterns of response. This sensor set was able to identify two unknown anion samples from ten closely-responding anions and could also function quantitatively, determining unknown concentrations of anions such as cyanide (as low as 1 mM) and selenate (as low as 50 μM). Further studies with calibration curves established detection limits of selected anions including thiocyanate (detection limit ~300 μM) and arsenate (~800 μM). The results demonstrate DNA-like fluorescent chemosensors as versatile tools for optically analyzing environmentally hazardous anions in aqueous environments.
Collapse
Affiliation(s)
- Hyukin Kwon
- Department of Chemistry , Stanford University , Stanford , California 94305-5080 , USA . ; Fax: +1 650 725 0259 ; Tel: +1 650 724 4741
| | - Wei Jiang
- Department of Chemistry , Stanford University , Stanford , California 94305-5080 , USA . ; Fax: +1 650 725 0259 ; Tel: +1 650 724 4741
| | - Eric T. Kool
- Department of Chemistry , Stanford University , Stanford , California 94305-5080 , USA . ; Fax: +1 650 725 0259 ; Tel: +1 650 724 4741
| |
Collapse
|
46
|
Sensitive determination of four β2-agonists in pig feed by capillary electrophoresis using on-line sample preconcentration with contactless conductivity detection. J Chromatogr B Analyt Technol Biomed Life Sci 2014; 973C:29-32. [DOI: 10.1016/j.jchromb.2014.10.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 10/01/2014] [Accepted: 10/03/2014] [Indexed: 01/26/2023]
|
47
|
Zhang M, Stamos BN, Dasgupta PK. Admittance Detector for High Impedance Systems: Design and Applications. Anal Chem 2014; 86:11547-53. [DOI: 10.1021/ac503247g] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Min Zhang
- Department of Chemistry and
Biochemistry, The University of Texas at Arlington, P.O. Box 76019-0065, Arlington, Texas 76019-0065, United States
| | - Brian N. Stamos
- Department of Chemistry and
Biochemistry, The University of Texas at Arlington, P.O. Box 76019-0065, Arlington, Texas 76019-0065, United States
| | - Purnendu K. Dasgupta
- Department of Chemistry and
Biochemistry, The University of Texas at Arlington, P.O. Box 76019-0065, Arlington, Texas 76019-0065, United States
| |
Collapse
|
48
|
Zhang M, Stamos BN, Amornthammarong N, Dasgupta PK. Capillary Scale Admittance Detection. Anal Chem 2014; 86:11538-46. [DOI: 10.1021/ac503245a] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Min Zhang
- Department of Chemistry and
Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
| | - Brian N. Stamos
- Department of Chemistry and
Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
| | - Natchanon Amornthammarong
- Department of Chemistry and
Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
| | - Purnendu K. Dasgupta
- Department of Chemistry and
Biochemistry, The University of Texas at Arlington, Arlington, Texas 76019-0065, United States
| |
Collapse
|
49
|
Kubáň P, Hauser PC. Contactless conductivity detection for analytical techniques-Developments from 2012 to 2014. Electrophoresis 2014; 36:195-211. [DOI: 10.1002/elps.201400336] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 08/05/2014] [Accepted: 08/05/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Pavel Kubáň
- Institute of Analytical Chemistry of the Academy of Sciences of the Czech Republic; Brno Czech Republic
| | - Peter C. Hauser
- Department of Chemistry; University of Basel; Basel Switzerland
| |
Collapse
|
50
|
Lan S, Xiong Y, Tian S, Sun L, Xie T, Wang X, Kong L. Simultaneous Determination of Cu-EDTA and Its Degradation Intermediates by Capillary Electrophoresis with a Capacitively Coupled Contactless Conductivity Detector. ELECTROANAL 2014. [DOI: 10.1002/elan.201400335] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|