1
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Li Z, Liu H, Wang D, Zhang M, Yang Y, Ren TL. Recent advances in microfluidic sensors for nutrients detection in water. Trends Analyt Chem 2023. [DOI: 10.1016/j.trac.2022.116790] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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2
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Couceiro P, Alonso-Chamarro J. Fluorescence Imaging Characterization of the Separation Process in a Monolithic Microfluidic Free-Flow Electrophoresis Device Fabricated Using Low-Temperature Co-Fired Ceramics. MICROMACHINES 2022; 13:mi13071023. [PMID: 35888840 PMCID: PMC9324176 DOI: 10.3390/mi13071023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/22/2022] [Accepted: 06/24/2022] [Indexed: 11/26/2022]
Abstract
A monolithic microfluidic free-flow electrophoresis device, fabricated using low-temperature co-fired ceramic technology, is presented. The device integrates gold electrodes and a 20 µm thick transparent ceramic optical window, suitable for fluorescence imaging, into a multilevel microfluidic chamber design. The microfluidic chamber consists of a 60 µm deep separation chamber and two, 50 µm deep electrode chambers separated by 10 µm deep side channel arrays. Fluorescence imaging was used for in-chip, spatial-temporal characterization of local pH variations in separation conditions as well as to characterize the separation process. The device allowed baseline resolution separation of a sample mixture of Fluorescein, Rhodamine 6G, and 4-Methylumbelliferone at pH 7.0, in only 6 s, using 378 V.s/cm. The results demonstrate the possibility of studying a chemical process using fluorescence imaging within the traditional fields of low-temperature co-fired ceramics technology, such as high-electrical-field applications, while using a simple fabrication procedure suitable for low-cost mass production.
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Calvo-López A, Ymbern O, Puyol M, Alonso-Chamarro J. Soluble reactive phosphorous determination in wastewater treatment plants by automatic microanalyzers. Talanta 2021; 221:121508. [PMID: 33076102 DOI: 10.1016/j.talanta.2020.121508] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/31/2020] [Accepted: 08/03/2020] [Indexed: 02/07/2023]
Abstract
The analysis of soluble reactive phosphate (SRP) in water is key to control water quality. In order to continuous monitor orthophosphate content in water during treatment processes and in the effluents of wastewater treatment plants, conventional procedures, usually performed in a laboratory, must be adapted. This means pursuing efforts on miniaturizing systems to operate in situ and automating analytical methods to work on-line. The design, construction and evaluation of an automatic and low cost cyclic olefin copolymer (COC)-based spectrophotometric microanalyzer, capable of operating in unattended conditions, is presented to monitor soluble reactive phosphorous, as orthophosphate ion, in wastewater samples coming from sewage treatment plants. The microsystem, constructed by CNC micromilling and using a multilayer approach, integrates microfluidics to carry out the phosphomolybdenum blue (PMB) reaction and an optical flow-cell for the spectrophotometric orthophosphate determination in a single polymeric substrate smaller than a credit card. It is connected to a compact optical detection system composed by a LED emitting at 660 nm and a PIN-photodiode, both integrated in a PCB. Flow management is automatically performed by programmed microvalves and micropumps, which control autocalibration processes and allow unattended operation. Analytical features after the optimization of the microfluidic platform and the chemical and the hydrodynamic variables, were a linear range from 0.09 to 32 mg L-1 P and a detection limit of 0.03 mg L-1 P with a sampling rate of 24 samples h-1, demonstrating the microanalyzer suitability for SRP monitoring in water. Moreover, real samples were analyzed obtaining promising results.
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Affiliation(s)
- Antonio Calvo-López
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Barcelona, Spain
| | - Oriol Ymbern
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Barcelona, Spain
| | - Mar Puyol
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Barcelona, Spain
| | - Julián Alonso-Chamarro
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Barcelona, Spain.
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Abstract
With the rapid development of high technology, chemical science is not as it used to be a century ago. Many chemists acquire and utilize skills that are well beyond the traditional definition of chemistry. The digital age has transformed chemistry laboratories. One aspect of this transformation is the progressing implementation of electronics and computer science in chemistry research. In the past decade, numerous chemistry-oriented studies have benefited from the implementation of electronic modules, including microcontroller boards (MCBs), single-board computers (SBCs), professional grade control and data acquisition systems, as well as field-programmable gate arrays (FPGAs). In particular, MCBs and SBCs provide good value for money. The application areas for electronic modules in chemistry research include construction of simple detection systems based on spectrophotometry and spectrofluorometry principles, customizing laboratory devices for automation of common laboratory practices, control of reaction systems (batch- and flow-based), extraction systems, chromatographic and electrophoretic systems, microfluidic systems (classical and nonclassical), custom-built polymerase chain reaction devices, gas-phase analyte detection systems, chemical robots and drones, construction of FPGA-based imaging systems, and the Internet-of-Chemical-Things. The technology is easy to handle, and many chemists have managed to train themselves in its implementation. The only major obstacle in its implementation is probably one's imagination.
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Affiliation(s)
- Gurpur Rakesh D Prabhu
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu, 30013, Taiwan.,Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu, 300, Taiwan
| | - Pawel L Urban
- Department of Chemistry, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu, 30013, Taiwan.,Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, 101, Section 2, Kuang-Fu Road, Hsinchu, 30013, Taiwan
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Shi Y, Liang L, Zuo Y, Zhu X, Yang Y, Xin H, Li B. Amplitude Holographic Interference-Based Microfluidic Colorimetry at the Micrometer Scale. J Phys Chem Lett 2020; 11:4747-4754. [PMID: 32407119 DOI: 10.1021/acs.jpclett.0c01204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Quantitative molecular analysis is usually based on spectrophotometric methods using colorimetric assay. Conventional methods, however, rely on the direct uniform absorption of the sample under test, and the detection sensitivity is strictly limited by the length of the absorption cell at the millimeter scale. Here, we report a new methodology for colorimetric assay based on the amplitude holographic interference (AHI) caused by nonuniform absorption of light, with detection sensitivity at the micrometer scale. In our method, the curved surface of the microfluidics results in a phase profile with a high diffraction efficiency, and the nonuniform absorption of samples exactly matches with the amplitude modulation in the holographic interference. The signal intensity is affected by not only direct sample absorption but also the sequential optical interference behind the liquid level. Both single- and multiple-wavelength colorimetric analyses of the Griess-Saltzman dye (GSD) were carried out using this method, and we found that the sensitivity can be improved by approximately 2-fold in comparison to the conventional method. This interference-based method would be a useful tool for the colorimetric assay of chemical samples in highly integrated systems with better performance.
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Affiliation(s)
- Yang Shi
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Li Liang
- School of Physics & Technology, Key Laboratory of Artificial Micro/Nano Structure of Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Yunfeng Zuo
- School of Physics & Technology, Key Laboratory of Artificial Micro/Nano Structure of Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Xiaoqiang Zhu
- Research Institute of Union Optech (Zhongshan) Co., Ltd., Zhongshan 528400, China
| | - Yi Yang
- School of Physics & Technology, Key Laboratory of Artificial Micro/Nano Structure of Ministry of Education, Wuhan University, Wuhan 430072, China
| | - Hongbao Xin
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
| | - Baojun Li
- Institute of Nanophotonics, Jinan University, Guangzhou 511443, China
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Guevara Amatón KV, Couceiro P, Coto Fuentes H, Calvo-Lopez A, Sández N, Moreno Casillas HA, Valdés Perezgasga F, Alonso-Chamarro J. Microanalyser Prototype for On-Line Monitoring of Copper(II) Ion in Mining Industrial Processes. SENSORS 2019; 19:s19153382. [PMID: 31374924 PMCID: PMC6695698 DOI: 10.3390/s19153382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 07/25/2019] [Accepted: 07/30/2019] [Indexed: 01/15/2023]
Abstract
A microanalyzer prototype for copper(II) ion monitoring in mining industrial processes is presented. The microanalyzer is designed as an assembly of different modules, each module being responsible for a unit operation. In order to optimize the industrial processes, the microanalyzer can automate all sample management, signal processing, and mathematical calculations and wirelessly transfer data to a control room. The determination of copper(II) ion is done using a colorimetric reaction and the microanalyser performs autocalibration by in situ dilution of a stock solution, matching the higher analyte concentration of the working range defined for the sample to be determined, using a multicommutation approach. The performance of the microanalyzer for monitoring copper(II) ion in water effluents of mining facilities was optimized in the working range from 1 to 10 mg/L to match Mexican environmental law regulations, which allow a maximum concentration of 4 mg/L of copper(II) ion in these circumstances.
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Affiliation(s)
| | - Pedro Couceiro
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Barcelona, Spain
| | - Hesner Coto Fuentes
- Instituto Tecnológico de la Laguna, México, Cuauhtémoc y Revolución s/n, Torreón Coahuila 27000, Mexico
| | - Antonio Calvo-Lopez
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Barcelona, Spain
| | - Natàlia Sández
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Barcelona, Spain
| | | | | | - Julián Alonso-Chamarro
- Group of Sensors and Biosensors, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Barcelona, Spain.
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Yan JC, Ren J, Ren LL, Jian JM, Yang Y, Yang SF, Ren TL. Development of a portable setup using a miniaturized and high precision colorimeter for the estimation of phosphate in natural water. Anal Chim Acta 2019; 1058:70-79. [DOI: 10.1016/j.aca.2019.01.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2018] [Revised: 12/20/2018] [Accepted: 01/14/2019] [Indexed: 10/27/2022]
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8
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Shi Y, Liu HL, Zhu XQ, Zhu JM, Zuo YF, Yang Y, Jiang FH, Sun CJ, Zhao WH, Han XT. Optofluidic differential colorimetry for rapid nitrite determination. LAB ON A CHIP 2018; 18:2994-3002. [PMID: 30128458 DOI: 10.1039/c8lc00690c] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nitrite detection plays a very important role in environmental monitoring and for industrial purposes. The commonly used colorimetric analysis requires the measurement of a system's calibration curve by asynchronously preparing and detecting a dozen standard samples, leading to time-consuming, slow and cumbersome procedures. Here, we present a differential colorimetry method that determines the nitrite level based on the paired chromaticity gradient, formed by coupling the colour reaction into the microfluidic network. The two gradients reshape each other and contain enough information for the quantitative analysis of the sample being tested, without the need for a calibration curve. The independence of the two gradients of the absorbance change caused by the detecting system and water quality results in a high stability and anti-interference performance, with the assistance of its self-correcting ability. This differential colorimetry method requires little time and energy consumption as only one sample is needed. Standard nitrite solutions of 0.50 mM and 0.33 mM have been determined with an error of 1.16% and 0.50%, respectively. These measurements are advantageous in terms of greater stability by up to 10 times and accuracy by 6 times, compared with the calibration curve approaches. It is foreseeable that this differential colorimetry method will find a wide range of applications in the field of chemical detection.
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Affiliation(s)
- Y Shi
- Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics & Technology, Wuhan University, Wuhan 430072, China.
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Suarez WT, Gabriel WL, de Alvarenga Junior BR, de Oliveira Krambeck Franco M, dos Santos VB. A Simplistic Portable LED-Based Photometer for In Situ Determination of Copper in Sugarcane Spirits. FOOD ANAL METHOD 2018. [DOI: 10.1007/s12161-018-1306-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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10
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Martinez-Cisneros C, da Rocha Z, Seabra A, Valdés F, Alonso-Chamarro J. Highly integrated autonomous lab-on-a-chip device for on-line and in situ determination of environmental chemical parameters. LAB ON A CHIP 2018; 18:1884-1890. [PMID: 29869662 DOI: 10.1039/c8lc00309b] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The successful integration of sample pretreatment stages, sensors, actuators and electronics in microfluidic devices enables the attainment of complete micro total analysis systems, also known as lab-on-a-chip devices. In this work, we present a novel monolithic autonomous microanalyzer that integrates microfluidics, electronics, a highly sensitive photometric detection system and a sample pretreatment stage consisting on an embedded microcolumn, all in the same device, for on-line determination of relevant environmental parameters. The microcolumn can be filled/emptied with any resin or powder substrate whenever required, paving the way for its application to several analytical processes: separation, pre-concentration or ionic-exchange. To promote its autonomous operation, avoiding issues caused by bubbles in photometric detection systems, an efficient monolithic bubble removal structure was also integrated. To demonstrate its feasibility, the microanalyzer was successfully used to determine nitrate and nitrite in continuous flow conditions, providing real time and continuous information.
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Calvo-López A, Puyol M, Casalta JM, Alonso-Chamarro J. Multi-parametric polymer-based potentiometric analytical microsystem for future manned space missions. Anal Chim Acta 2017; 995:77-84. [DOI: 10.1016/j.aca.2017.08.043] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 08/01/2017] [Accepted: 08/28/2017] [Indexed: 11/30/2022]
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12
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Suarez WT, de Alvarenga Junior BR, de Oliveira Krambeck Franco M, Gabriel WL, de Oliveira DM, dos Santos VB. In Situ Determination of Urea in Milk Employing a Portable and Low-Cost LED Photometer. FOOD ANAL METHOD 2017. [DOI: 10.1007/s12161-017-1087-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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13
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Couceiro P, Alonso-Chamarro J. Microfabrication of Monolithic Microfluidic Platforms Using Low Temperature Co-Fired Ceramics Suitable for Fluorescence Imaging. Anal Chem 2017; 89:9147-9153. [DOI: 10.1021/acs.analchem.7b01889] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Pedro Couceiro
- Sensors and Biosensors Group,
Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia Spain
| | - Julián Alonso-Chamarro
- Sensors and Biosensors Group,
Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia Spain
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14
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Peroxynitrous-acid-induced chemiluminescence detection of nitrite based on Microfluidic chip. Talanta 2016; 154:73-9. [DOI: 10.1016/j.talanta.2016.03.062] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 03/14/2016] [Accepted: 03/19/2016] [Indexed: 01/09/2023]
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15
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Ymbern O, Berenguel-Alonso M, Calvo-López A, Gómez-de Pedro S, Izquierdo D, Alonso-Chamarro J. Versatile Lock and Key Assembly for Optical Measurements with Microfluidic Platforms and Cartridges. Anal Chem 2015; 87:1503-8. [DOI: 10.1021/ac504255t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Oriol Ymbern
- Sensors & Biosensors Group, Department of Chemistry, Universitat Autònoma de Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia, Spain
| | - Miguel Berenguel-Alonso
- Sensors & Biosensors Group, Department of Chemistry, Universitat Autònoma de Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia, Spain
| | - Antonio Calvo-López
- Sensors & Biosensors Group, Department of Chemistry, Universitat Autònoma de Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia, Spain
| | - Sara Gómez-de Pedro
- Sensors & Biosensors Group, Department of Chemistry, Universitat Autònoma de Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia, Spain
| | - David Izquierdo
- Centro Universitario de la Defensa, Academia General Militar, Carretera de Huesca, s/n, 50090 Zaragoza, Spain
| | - Julián Alonso-Chamarro
- Sensors & Biosensors Group, Department of Chemistry, Universitat Autònoma de Barcelona, Edifici Cn, 08193 Bellaterra, Catalonia, Spain
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Batista AD, Sasaki MK, Rocha FRP, Zagatto EAG. Flow analysis in Brazil: contributions over the last four decades. Analyst 2014; 139:3666-82. [DOI: 10.1039/c4an00295d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Timeline with the main contributions of Brazilian researchers to flow analysis.
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Affiliation(s)
- Alex D. Batista
- Centro de Energia Nuclear na Agricultura
- Universidade de São Paulo
- Piracicaba, Brazil
| | - Milton K. Sasaki
- Centro de Energia Nuclear na Agricultura
- Universidade de São Paulo
- Piracicaba, Brazil
| | - Fábio R. P. Rocha
- Centro de Energia Nuclear na Agricultura
- Universidade de São Paulo
- Piracicaba, Brazil
| | - Elias A. G. Zagatto
- Centro de Energia Nuclear na Agricultura
- Universidade de São Paulo
- Piracicaba, Brazil
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Kovarik ML, Ornoff DM, Melvin AT, Dobes NC, Wang Y, Dickinson AJ, Gach PC, Shah PK, Allbritton NL. Micro total analysis systems: fundamental advances and applications in the laboratory, clinic, and field. Anal Chem 2013; 85:451-72. [PMID: 23140554 PMCID: PMC3546124 DOI: 10.1021/ac3031543] [Citation(s) in RCA: 170] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Michelle L. Kovarik
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Douglas M. Ornoff
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Adam T. Melvin
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Nicholas C. Dobes
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Yuli Wang
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Alexandra J. Dickinson
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Philip C. Gach
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Pavak K. Shah
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC 27695
| | - Nancy L. Allbritton
- Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC 27599 and North Carolina State University, Raleigh, NC 27695
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18
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Campos CDM, da Silva JAF. Applications of autonomous microfluidic systems in environmental monitoring. RSC Adv 2013. [DOI: 10.1039/c3ra41561a] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
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Xin Y, Wang Q, Liu T, Wang L, Li J, Fang Y. A portable and autonomous multichannel fluorescence detector for on-line and in situ explosive detection in aqueous phase. LAB ON A CHIP 2012; 12:4821-4828. [PMID: 23007322 DOI: 10.1039/c2lc40804j] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A multichannel fluorescence detector used to detect nitroaromatic explosives in aqueous phase has been developed, which is composed of a five-channel sample-sensor unit, a measurement and control unit, a microcontroller, and a communication unit. The characteristics of the detector as developed are mainly embedded in the sensor unit, and each sensor consists of a fluorescent sensing film, a light emitting diode (LED), a multi-pixel photon counter (MPPC), and an optical module with special bandpass optical filters. Due to the high sensitivity of the sensing film, the small size and low cost of LED and MPPC, the developed detector not only has a better detecting performance and small size, but also has a very low cost - it is an alternative to the device made with an expensive high power lamp and photomultiplier tube. The wavelengths of the five sensors covered extend from the upper UV through the visible spectrum, 370-640 nm, and thereby it possesses the potential to detect a variety of explosives and other hazardous materials in aqueous phase. An additional function of the detector is its ability to function via a wireless network, by which the data recorded by the detector can be sent to the host computer, and at the same time the instructions can be sent to the detector from the host computer. By means of the powerful computing ability of the host computer, and utilizing the classical principal component analysis (PCA) algorithm, effective classification of the analytes is achieved. Furthermore, the detector has been tested and evaluated using NB, PA, TNT and DNT as the analytes, and toluene, benzene, methanol and ethanol as interferent compounds (concentration various from 10 and 60 μM). It has been shown that the detector can detect the four nitroaromatics with high sensitivity and selectivity.
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Affiliation(s)
- Yunhong Xin
- School of Physics and Information Technology, Shaanxi Normal University, Xi'an 710062, PR China.
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