CdS Nanoparticle-based Biosensor Development for Aflatoxin Determination

Self Cite

A micro-band boron-doped diamond (BDD) electrode was prepared by sealing a piece of BDD film with an area of 1.1110 -7 m 2 between two insulating plates, one Teflon and one silicon rubber, to form sandwich-like layers, so the surface area could be investigated. The micro-band BDD was combined with capillary zone electrophoresis as an electrode for the simultaneous detection of adenosine monophosphate (AMP), adenosine diphosphate (ADP), and adenosine triphosphate (ATP) in a solution. These adenosine phosphates can be separated with a 0.3 m-long fused silica capillary using Britton-Robinson buffers at pH 2.0. Current in the concentration range of 0.1 to 2.0 mM were linear with the limits of detection of 0.004 μM, 0.006 μM, and 0.011 μM for AMP, ADP, and ATP, respectively. A comparison with an unmodified BDD as the detector in the same electrophoresis system showed that the micro-band generated better limits of detection (LODs) than the macroelectrode. This method was successfully applied to human urine samples injected with three adenosine phosphates, as well as adenine and guanine, which can be well-separated with recovery percentages of adenine, guanine, AMP, ADP, and ATP of 99.2%, 102.5%, 107.4%, 107.7%, and 105.4%, respectively.

Section: Introductionmentioning

confidence: 88%

Micro-band Boron-doped Diamond Electrode in Capillary Electrophoresis for Simultaneous Detection of AMP, ADP, and ATP

Prayikaputri¹,

Jiwanti²,

Nasution³

et al. 2021

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“…On the other hand, voltammetric electronic tongues work with electrodes o sensors made of noble metals (platinum, gold, iridium, rhodium, and palladium) or modified electrodes (Arrieta et al, 2020;Wei et al, 2013;Alcañiz et al, 2012). In contrast to potentiometric sensors, they are not limited to detecting charged species and possess desirable properties such as versatility, robustness, and simplicity (Hayat et al, 2019;Khalil et al, 2018). Nevertheless, systems based on metallic electrodes offer poorly resolved voltammetric signals with little information because the curves do not represent defined electrochemical processes by the concept (Winquist et al, 2005).…”

Section: Introductionmentioning

confidence: 99%

Application of a Polypyrrole Sensor Array Integrated into a Smart Electronic Tongue for the Discrimination of Milk Adulterated with Sucrose

Arrieta¹,

Barrera²,

Mendoza³

2023

This work presents the use of a smart electronic tongue for discriminating adulterated milk samples with various concentrations of sucrose. The smart electronic tongue was integrated by a voltammetric sensor array from polypyrrole doped with various doping agents, a portable multi-potentiostat controlled by a smartphone with an Android application. Sucrose concentrations ranging from 1% to 20% were used to adulterate the tested samples. The sensor array was optimized to perform measurements on milk while maintaining good performance in terms of stability and signal quality. The sensor array was prepared by chronoamperometric electropolymerization of pyrrole with different doping agents, varying polymerization time (from 50 to 300 s), and concentration of monomer (from 0.10 to 0.40 M) and doping agent (from 0.05 to 0.30 M). The optimization process results demonstrated that the parameters polymerization time, monomer concentration, and doping agent concentration affect the stability of the signals in the sensors, allowing for the establishment of adequate conditions to guarantee maximum stability through an experimental design. Thus, values of 0.10 M for monomer concentration, 0.05 to 0.10 M for doping agent concentration, and 50 to 70 s for polymerization time were established. The measurements taken with the smart electronic tongue on the milk samples allowed a principal component analysis to classify the samples in the plane of the first two principal components. Principal components 1 and 2 registered a variance of 93.39% (78.68% and 14.71%, respectively), indicating a high degree of information registered by the sensor array. It could be concluded that the array of optimized polypyrrole sensors allows sufficient information to be recorded through measurements made with the smart electronic tongue to discriminate adulterated milk samples with different sucrose concentrations.

“…Various methods have been developed for the detection of DA. Biosensorbased electrochemical sensors are highly accurate, user friendly, and have a quick response time (Rahman, et al, 2016b;Hayat et al, 2019). Recently, chemically modified electrodes were established and reported with greater sensitivity and selectivity to effectively detect DA (Zhang et al, 2013;Wu et al, 2014;Xu et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

Amperometric Detection of Dopamine based on a Graphene Oxide/PEDOT:PSS Composite Electrode

Hardi¹,

Rahman²

2020

Dopamine (DA) is a hormone and a neurotransmitter that plays many important roles within the brain and body. It is an organic compound in the catecholamines and phenethylamines groups. A considerable effort has been made since its discovery, and numerous techniques for DA detection have been developed. Graphene and its derivatives have great potential for the development of sensors and biosensors. Since it has excellent characteristics, such as good conductivity and a large surface area, a graphene-based biosensor is expected to have high sensitivity, selectivity, and long-term stability characteristics. Graphene oxide (GO) was synthesized using a chemical method through graphite oxidation. Graphene oxide/poly (3,4-ethylenedioxythiophene):poly (4-styrenesulfonate) (GO/PEDOT:PSS) composite films were prepared using an electropolymerization method on the surface of the working electrode. The properties of this composite electrode were characterized by cyclic voltammetry (CV) and scanning electron microscopy (SEM). The performance of the composite film was evaluated using three-electrode systems that consisted of a glassy carbon electrode (GCE) modifying a composite film electrode as a working electrode, a platinum electrode as an auxiliary electrode, and Ag/AgCl as a reference electrode. The variation of the composite electrode was applied and evaluated to DA electrochemical sensing. The GO/PEDOT:PSS-modified electrode also exhibits high performance with a low detection limit of 1 μM. The results obtained have shown that GO/PEDOT:PSS/GCE composites are promising candidates for modifying electrode material used in electrochemical sensing.