基于微流控热生物传感器的L-谷氨酸免标记检测

Label Free Detection of L-Glutamate Using Microfluidic Based Thermal Biosensor.

作者信息

Kopparthy Varun Lingaiah, Tangutooru Siva Mahesh, Guilbeau Eric J

机构信息

The Center for Biomedical Engineering and Rehabilitation Science, Louisiana Tech University, Ruston, LA 71272, USA.

Department of Mechanical & Industrial Engineering, Qatar University, P.O. Box 2713, Doha, Qatar.

出版信息

Bioengineering (Basel). 2015 Jan 12;2(1):2-14. doi: 10.3390/bioengineering2010002.

DOI:10.3390/bioengineering2010002

PMID:28955010

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5597124/

Abstract

A thermoelectric biosensor for the detection of L-glutamate concentration was developed. The thermoelectric sensor is integrated into a micro-calorimeter which measures the heat produced by biochemical reactions. The device contains a single flow channel that is 120 µm high and 10 mm wide with two fluid inlets and one fluid outlet. An antimony-bismuth (Sb-Bi) thermopile with high common mode rejection ratio is attached to the lower channel wall and measures the dynamic changes in the temperature when L-glutamate undergoes oxidative deamination in the presence of glutamate oxidase (GLOD). The thermopile has a Seebeck coefficient of ~7 µV·(m·K). The device geometry, together with hydrodynamic focusing, eliminates the need of extensive temperature control. Layer-by-layer assembly is used to immobilize GLOD on the surface of glass coverslips by alternate electrostatic adsorption of polyelectrolyte and GLOD. The impulse injection mode using a 6-port valve minimizes sample volume to 5 µL. The sensitivity of the sensor for glutamate is 17.9 nVs·mM in the linear range of 0-54 mM with an R² value of 0.9873. The lowest detection limit of the sensor for glutamate is 5.3 mM.

摘要

开发了一种用于检测L-谷氨酸浓度的热电生物传感器。该热电传感器集成在一个微热量计中，该微热量计可测量生化反应产生的热量。该装置包含一个单一流道，其高度为120 µm，宽度为10 mm，有两个流体入口和一个流体出口。一个具有高共模抑制比的锑铋（Sb-Bi）热电堆附着在通道下壁，用于测量在谷氨酸氧化酶（GLOD）存在下L-谷氨酸发生氧化脱氨时的温度动态变化。该热电堆的塞贝克系数约为7 µV·(m·K)。该装置的几何结构与流体动力学聚焦相结合，无需进行广泛的温度控制。通过聚电解质和GLOD的交替静电吸附，采用层层组装法将GLOD固定在玻璃盖玻片表面。使用6通阀的脉冲进样模式可将样品体积最小化至5 µL。该传感器对谷氨酸的灵敏度在0-54 mM的线性范围内为17.9 nVs·mM，R²值为0.9873。该传感器对谷氨酸的最低检测限为5.3 mM。