TY - JOUR
T1 - A developed competitive immunoassay based on impedance measurements for methamphetamine detection
AU - Yeh, Chia Hsien
AU - Wang, Wei Ting
AU - Shen, Pi Lan
AU - Lin, Yu Cheng
N1 - Funding Information:
Acknowledgments The authors would like to thank the Center for Micro/Nano Technology, National Cheng Kung University, Tainan, Taiwan, ROC for access to equipment and technical support. This research was partially supported by the Southern Taiwan Science Park Administration (STSPA), Taiwan, ROC under contract no. 99RC06 and 100CB02. The work was also partially supported by NCKU Top 100 University Advancement and the ‘‘Aim for the Top University Plan’’ of the National Chiao Tung University and Ministry of Education, Taiwan, ROC.
Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/9
Y1 - 2012/9
N2 - In this study, an electro-microchip was successfully used to detect the impedance signals of various methamphetamine (MET) concentrations based on the developed competitive immunoassay method. MET is a commonly used drug often abused by drug addicts and can cause irregular behavior; therefore, MET concentration detection is important for quantitative analysis. In this study, gold nanoparticles (AuNPs) were introduced into an electro-microchip through the specific binding of antibodies, thus constructing a bridge between two electrodes and allowing electrons to move between them. The decreasing impedance value can be easily measured with a commercial LCR meter. According to the collected measurements, a significant difference was observed in impedance signals after 13 min when MET concentrations were reduced. Additionally, a clear, distinguished impedance (a steep slope for both impedance and MET concentration) in the frequency effect (100 Hz-1 MHz) was observed at 100 Hz. When the concentration of the anti-MET antibody- colloidal gold conjugates was diluted 1009, the detectable limit for MET concentration was 1 ng/mL with 0.5 lg/mL of BSA-MET conjugate. Therefore, the developed electro-microchip is advantageous because it is effective with small sample volumes (30 lL), is a form of rapid quantitative measurement, and works with smaller detectable concentrations than other existing commercial detection prducts which have the best limit of detection of 100 ng/mL.
AB - In this study, an electro-microchip was successfully used to detect the impedance signals of various methamphetamine (MET) concentrations based on the developed competitive immunoassay method. MET is a commonly used drug often abused by drug addicts and can cause irregular behavior; therefore, MET concentration detection is important for quantitative analysis. In this study, gold nanoparticles (AuNPs) were introduced into an electro-microchip through the specific binding of antibodies, thus constructing a bridge between two electrodes and allowing electrons to move between them. The decreasing impedance value can be easily measured with a commercial LCR meter. According to the collected measurements, a significant difference was observed in impedance signals after 13 min when MET concentrations were reduced. Additionally, a clear, distinguished impedance (a steep slope for both impedance and MET concentration) in the frequency effect (100 Hz-1 MHz) was observed at 100 Hz. When the concentration of the anti-MET antibody- colloidal gold conjugates was diluted 1009, the detectable limit for MET concentration was 1 ng/mL with 0.5 lg/mL of BSA-MET conjugate. Therefore, the developed electro-microchip is advantageous because it is effective with small sample volumes (30 lL), is a form of rapid quantitative measurement, and works with smaller detectable concentrations than other existing commercial detection prducts which have the best limit of detection of 100 ng/mL.
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U2 - 10.1007/s10404-012-0964-0
DO - 10.1007/s10404-012-0964-0
M3 - Article
AN - SCOPUS:84867229935
VL - 13
SP - 319
EP - 329
JO - Microfluidics and Nanofluidics
JF - Microfluidics and Nanofluidics
SN - 1613-4982
IS - 2
ER -