A bifunctional derivative of the thrombin-binding aptamer with a redox-active Fc moiety and a thiol group at the termini of the aptamer strand was synthesized. The ferrocene-labeled aptamer thiol was self-assembled through S-Au bonding on a polycrystalline gold electrode surface and the surface was blocked with 2-mercaptoethanol to form a mixed monolayer. By use of a fluorescent molecular beaco...

Abstract Assessment of human epidermal growth factor receptor-2 (HER2) tumor marker status is an impressive in screening, diagnosing and monitoring breast cancer (BC). The electrochemical biosensor a revolutionary method diagnosis, which used this research to detect HER2 + circulating cells. activity, size, shape, morphology the synthesized nanomaterials were analyzed. hybrid nanocomposite esta...

According to documented reports, more than 200 million people across the globe are exposed arsenic (As) contamination at levels above World Health Organization (WHO) guideline limit of 10 μg/L. In this work, a novel fluorescence OFF-ON ultrasensitive aptasensor was developed for As (III). To construct aptasensor, AuFeZnSe alloyed quantum dots (QDs) were newly synthesized and surface-coated with...

Objective (s): In light of misuse of antibiotics in animal husbandry and their side effects on human health, there is an argent need to develop simple and rapid methods for determining the quantification of antibiotics in biological systems. Materials and Methods: In this work a facile and ultrasensitive colorimetric aptasensor was reported for detection of oxytetracycline (OTC) in water and mi...

A label-free electrochemical nucleic acid aptasensor for the detection of methamphetamine (MA) by the immobilization of thiolated self-assembled DNA sequences on a gold nanoparticles-chitosan modified electrode is constructed. When MA was complexed specifically to the aptamer, the configuration of the nucleic acid aptamer switched to a locked structure and the interface of the biosensor changed...