Layered Double Hydroxide-Modified Organic Electrochemical Transistor for Glucose and Lactate Biosensing
Layered Double Hydroxide-Modified Organic Electrochemical Transistor for Glucose and Lactate Biosensing
复制标题
DOI：
10.3390/s20123453
复制
发表时间：
2020-06-01
期刊：
影响因子：
3.9
通讯作者：
Scavetta, Erika
中科院分区：
文献类型：
--
作者：
Gualandi, Isacco;Tessarolo, Marta;Scavetta, Erika
基于有机电化学晶体管（OECT）的生物传感器被开发用于选择性检测葡萄糖和乳酸。晶体管架构提供了相对于简单电流响应的信号放大（增益）。该生物传感器基于聚（3,4-乙撑二氧噻吩）：聚（苯乙烯磺酸）（PEDOT：PSS）通道，栅电极通过葡萄糖氧化酶（GOx）或乳酸氧化酶（LOx）进行功能化，这些酶通过一步电沉积程序固定在镍/铝层状双氢氧化物（LDH）内。这里设计的 OECT 架构可以最大限度地减少电沉积过程中所需的酶量。生物传感器的输出信号是漏极电流（I-d），它随着分析物浓度的增加而减小。在优化条件下，生物传感器对 0.1-8.0 mM 范围内的葡萄糖作出响应，检测限 (LOD) 为 0.02 mM。观察到两种比例制度。对于低于 1.0 mM 的浓度，获得平均增益为 360 的线性响应，而对于高于 1.0 mM 的浓度，I(d) 与葡萄糖浓度的对数成正比，增益为 220。对于乳酸检测，生物传感器响应在整个浓度范围 (0.05-8.0 mM) 内呈线性。 LOD 达到 0.04 mM，净增益等于 400。
Biosensors based on Organic Electrochemical Transistors (OECTs) are developed for the selective detection of glucose and lactate. The transistor architecture provides signal amplification (gain) with respect to the simple amperometric response. The biosensors are based on a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) channel and the gate electrode is functionalised with glucose oxidase (GOx) or lactate oxidase (LOx) enzymes, which are immobilised within a Ni/Al Layered Double Hydroxide (LDH) through a one-step electrodeposition procedure. The here-designed OECT architecture allows minimising the required amount of enzyme during electrodeposition. The output signal of the biosensor is the drain current (I-d), which decreases as the analyte concentration increases. In the optimised conditions, the biosensor responds to glucose in the range of 0.1-8.0 mM with a limit of detection (LOD) of 0.02 mM. Two regimes of proportionality are observed. For concentrations lower than 1.0 mM, a linear response is obtained with a mean gain of 360, whereas for concentrations higher than 1.0 mM,I(d)is proportional to the logarithm of glucose concentration, with a gain of 220. For lactate detection, the biosensor response is linear in the whole concentration range (0.05-8.0 mM). A LOD of 0.04 mM is reached, with a net gain equal to 400.