Biosensors designed for environmental and food quality control based on screen-printed graphite electrodes with different configurations

Abstract

Graphite electrodes fabricated by screen-printing have been used as amperometric detectors in biosensors based on NAD(+)-dependent dehydrogenases, tyrosinase, or genetically modified acetylcholinesterases. The mono-enzyme sensors have been optimized as disposable or reusable devices for detection of a variety of substrates important in the food industry ( D-lactic acid, L-lactic acid, acetaldehyde) or in environmental pollution control (phenols and dithiocarbamate, carbamate and organophosphorus pesticides). The sensors were prepared in four configurations differing in enzyme confinement, enzyme immobilization and location of the immobilization agent in the biosensor assembly. Tests on real samples have been performed with the biosensors; D-lactic acid and acetaldehyde have been detected in wine and phenols in air.

Biosensors for Life Sciences

“…So, in the following inhibition studies it may be assumed that only the influence of the organophosphorus pesticide from the synthetic samples or the organophosphorus and carbamates pesticides are important. The similar results were also obtained by other researchers for other immobilised enzymes, using different immobilisation method and different working procedure ( Avramescu et al, 2002;Montesinos et al, 2001). The inhibition tests regard the organophosphorus pesticides action over different origin acetylcholinesterase.…”

“…8). Using this dependency there might be obtained I20 and respectively I50 with the values 6.6⋅10 -9 M, respective 1.4⋅10 -8 M methyl paraoxon, versus E107W, the results being in concordance with literature data (Andreescu et al, 2002) The detection limit for organophosphorus pesticides analysis is around 10 -9 -5 10 -7 M, depending by the pesticide and by biosensors obtaining protocol (Evtugyn et al, 1996;Ivanov et all, 2003). The same increase of inhibition degree was also observed for immobilised mutant Dm acetylcholinesterase E107Y, using the same procedure sol-gel M.4.1.…”

A Simple Procedure to Fabricate Paper Biosensor and Its Applicability—NADH/NAD+ Redox System

“…Investigation in this area usually explores the mediator use or the surface modification to improve the electrochemical detection [15,21,[24][25][26][27][28]. Some literature has been published related to the study of the redox couple NADH/NAD + in screen printing electrodes [1,4,21,[24][25][26][27][29][30][31][32][33][34]. The sensor built using this technique can incorporate the three electrodes (working electrode, reference and counter electrode), can be easily produced and miniaturized, work with a minimum volume (2 µL), it needs low reagent consumption, it can be fabricated in many supports (paper, glass) and sensors are disposable devices that can be used in many science fields [26,35].…”

Copper nanoparticles applied to the preconcentration and electrochemical determination of β-adrenergic agonist: An efficient tool for the control of meat production

“…Among the electrochemical techniques, square-wave voltammetry (SWV) combined with the use of screen-printed carbon electrodes (SPCE) as the detection system represents an attractive alternative [18,19]. The main advantages of the SPCE include simplicity, versatility, low cost, portability, reliability, small size, mass production capabilities, and minimum sample volume required (20-40 µL) [20,21].…”