Abstract This article reviews recent achievements in developing aptamer‐based electrochemical biosensors (electrochemical aptasensors). Aptamers are single stranded DNA or RNA molecules with high specificity to various ligands. Their is comparable and certain cases even higher than those of antibodies. In contrast antibodies, aptamers prepared by an vitro selection procedure developed simultaneously the early 1990s L. Gold A. Ellington. Due their stability possibility chemical modification...

Abstract We report a high sensitive biosensor based on DNA aptamers for detection of ochratoxin A (OTA). The thiolated specific to OTA different configurations have been immobilized by chemisorption the surface gold electrode. Electrochemical impedance spectroscopy (EIS) in presence redox probe [Fe(CN) 6 ] −3/−4 has used determination charge transfer resistance, R ct , followed addition OTA. increased with increasing concentration range 0.1–100 nM. limit (0.12–0.40 nM) depended configuration...

Abstract Novel electrochemical aptasensors based on glassy carbon electrodes modified with electropolymerized Neutral red and polycarboxylated macrocyclic ligands onto which the DNA aptamers were covalently attached have been developed for detection of Aflatoxin B1 (AFB1). The interaction an analyte resulted in decrease cathodic peak current probe measured by CV increase electron transfer resistance determined EIS. limit was found to be 0.1 nM 0.05 EIS methods, respectively. aptasensor makes...

The present work aims to develop an electrochemical biosensor based on aptamer able detect human cellular prions PrP(C) as a model biomarker of prion disease with high sensitivity. We designed the using multiwalled carbon nanotubes (MWCNTs) modified polyamidoamine dendrimers fourth generation (PAMAM G4) which in turn were coupled DNA aptamers used bioreceptors. Electrochemical signal was detected by ferrocenyl redox marker incorporated between and interlayer. MWCNTs, thanks their...

Heavy metal ions (HMIs) have acute toxic effects on health and are dangerous for human existence the ecosystem. Therefore, their sensitive selective detection is of great importance. In recent years, various nanocomposite materials been used by researchers HMIs using modalities electrochemical techniques. This review summarizes advances in developing sensors based numerous detecting HMIs. Nanocomposite materials, such as metal–organic frameworks (MOFs), organic conducting polymer (OCPs),...

Abstract The emergence of toxic pollutants due to heavy human intervention in the ecosystem causes serious environmental problems. Therefore, sensors based on material having a strong affinity towards specific gaseous are urgently needed. present study deals with chemiresistive gas for detection sulfur dioxide (SO 2 ) composite reduced graphene oxide (rGO) and 5,10,15,20-tetrakis(4-aminophenyl) porphyrin (TAPP). improved Hummers method was used synthesize (GO); it further thermally rGO....

Layer-by-layer (LbL) immobilization of DNA aptamers in the realm electrochemical detection heavy metal ions (HMIs) offers an enhancement specificity, sensitivity, and low limits by leveraging cross-reactivity obtained from multiple interactions between immobilized developed material surfaces. In this research, we present a LbL approach for thiol- amino-modified on Ag-incorporated cobalt-succinate metal-organic framework (MOF) (Ag@Co-Succinate) to achieve cross-reactive effect behavior...

Novel affinity biosensors for detecting cellular prions, PrPC, based on DNA aptamers and antibodies immobilized onto the carbon nanotubes have been designed compared in accordance with their binding ability analytical performance. The allowed us to detect PrPC limits of detection 20 50 pM. Keywords: Prion proteins, aptamers, antibodies, biosensor, multiwalled nanotubes, electrochemical quartz crystal microbalance

An impedimetric aptasensor for ochratoxin A (OTA) detection has been developed on the base of a gold electrode covered with new modifier consisting electropolymerized Neutral Red and mixture Au nanoparticles suspended in dendrimeric polymer Botlorn H30®. Thiolated aptamer specific to OTA was covalently attached via Au-S bonding. The interaction induced conformational switch from linear guanine quadruplex form followed by consolidation surface layer an increase charge transfer resistance....

Herein, we report ultrasound-propelled graphene-oxide coated gold nanowire motors, functionalized with fluorescein-labeled DNA aptamers (FAM-AIB1-apt), for qualitative detection of overexpressed AIB1 oncoproteins in MCF-7 breast cancer cells. The movement nanomotors under the ultrasound field facilitated intracellular uptake and resulted a faster aptamer binding target protein thus fluorescence recovery. propulsion behavior greatly enhanced intensity compared to static conditions. new...

Modern analysis of food and feed is mostly focused on development fast reliable portable devices intended for field applications. In this review, electrochemical biosensors based immunological reactions aptamers are considered in the determination mycotoxins as one most common contaminants able to negatively affect human health. The characteristics from point view general principles bioreceptor implementation signal transduction providing sub-nanomolar detection limits mycotoxins. Moreover,...

Milk is a significant foodstuff around the world, being produced and consumed in large quantities. The safe consumption of milk requires that liquid has an acceptably low level microbial contamination not been subjected to spoiling. Bacterial safety limits vary by country but are typically thousands per mL sample. To rapidly determine if samples contain unsafe bacteria, aptamer-based sensor specific Escherichia coli bacteria was developed. based on ultra-high frequency electromagnetic...