Screen-Printed Carbon Electrodes Modified with Graphene Oxide for the Design of a Reagent-Free NAD⁺-Dependent Biosensor Array

Abstract

A facile approach for the construction of reagent-free electrochemical dehydrogenase-based biosensors is presented. Enzymes and cofactors (NAD+ and Fe­(CN)6 3–) were immobilized by modification of screen-printed carbon electrodes with graphene oxide (GO) and an additional layer of cellulose acetate. The sensor system was exemplarily optimized for an l-lactate electrode in terms of GO concentration, working potential, and pH value. The biosensor exhibited best characteristics at pH 7.5 in 100 mM potassium phosphate buffer at an applied potential of +0.250 V versus an internal pseudo Ag reference electrode. Thereby, sensor performance was characterized by a linear working range from 0.25 to 4 mM and a sensitivity of 0.14 μA mM–1. The detection principle was additionally evaluated with three other dehydrogenases (d-lactate dehydrogenase, alcohol dehydrogenase, and formate dehydrogenase, respectively). The developed reagentless biosensor array enabled simultaneous and cross-talk free determination of l-lactate, d-lactate, ethanol, and formate.

Towards smart biomanufacturing: a perspective on recent developments in industrial measurement and monitoring technologies for bio-based production processes

“…Due to their properties, these sensors have the capability of providing fast, cost effective and reliable analytical results [43], which together with expanding computation power, enables the use of biosensors as another promising solution enabling the drive towards smart manufacturing. Recently, several biosensors have been developed for the control and monitoring of many different analytes [44,48,49]. In particular, biosensors for the on-line determination of glucose, glutamate, and lactate are available [49,50], which are delivered ready to use and can be directly integrated with bioreactors via standard ports.…”

“…Recently, several biosensors have been developed for the control and monitoring of many different analytes [44,48,49]. In particular, biosensors for the on-line determination of glucose, glutamate, and lactate are available [49,50], which are delivered ready to use and can be directly integrated with bioreactors via standard ports. However, these sensors are still in the development stage and are not used in industrial scale production processes.…”

Graphene Oxide-Based Nanohybrids as Pesticide Biosensors: Latest Developments

“…The most common example is the determination of glucose, which has an important role in the diagnosis and therapy of diabetes. Apart from glucose oxidase based biosensors, other enzyme-based biosensors are also known with high sensitivity and selectivity, which includes biosensors based on alcohol dehydrogenase [140], microperoxidase [141], horseradish peroxidase [142], tyrosinase [143], urease [144], and acetylcholinesterase [145]. Acetylcholinesterase (AChE) is a catalytic enzyme present in the central nervous system, which catalyzes the hydrolysis of acetylcholine and choline esters.…”

Light-addressable Electrodes for Dynamic and Flexible Addressing of Biological Systems and Electrochemical Reactions

“…Charge transfer is the main task of working electrodes in electrochemistry, while they are in steady interaction with an electrolyte [1][2][3][4]. The overall application field of biosensors [5][6][7] extends from enzymatic biosensors [8][9][10] and impedimetric DNA sensors [11] to detection of action potentials of neurons with microelectrode arrays [12]. Depending on the application, electrode sizes range from macro-and micro-down to nanoelectrodes with adjustable geometries [13][14][15].…”