For the first time an electrochemical sensor based on nanomaterial-supported molecularly imprinted polymers (MIPs) is applied to the sensitive and specific determination of chloroquine phosphate (CHL). The sensor was produced using an electropolymerization (EP) approach, and it was formed on a glassy carbon electrode (GCE) using CHL as a template and 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) and aniline (ANI) as functional monomers. Incorporating Prussian blue polyethyleneglycol-amine nanoparticles (PB@PEG-NH) in the MIP-based electrochemical sensor increased the active surface area and porosity.
View Article and Find Full Text PDFThe current situation of the Covid-19 pandemic is indicated by a huge number of infections, high lethality, and rapid spread. These circumstances have stopped the activity of almost the entire world, affecting severely the global economy. A rapid diagnosis of the Covid-19 and a generalized testing protocol is essential to fight against the pandemic and to maintain health control in the population.
View Article and Find Full Text PDFThe effect of graphene oxidative grades upon the conductivity and hydrophobicity and consequently the influence on an enzymatic biosensing response is presented. The electrochemical responses of reduced graphene oxide (rGO) have been compared with the responses obtained from the oxide form (oGO) and their performances have been accordingly discussed with various evidences obtained by optical techniques. We used tyrosinase enzyme as a proof of concept receptor with interest for phenolic compounds detection through its direct adsorption onto a screen-printed carbon electrode previously modified with oGO or rGO with a carbon-oxygen ratio of 1.
View Article and Find Full Text PDFA disposable immunosensor for Salmonella enterica subsp. enterica serovar Typhimurium LT2 (S) detection using a magneto-immunoassay and gold nanoparticles (AuNPs) as label for electrochemical detection is developed. The immunosensor is based on the use of a screen-printed carbon electrode (SPCE) that incorporates a permanent magnet underneath.
View Article and Find Full Text PDFNanoparticles serve as fundamental building blocks for nanobiotechnology, especially in several applications in the development of novel (bio)sensing systems. Nanoparticles can be used for modification of the surfaces of (bio)sensing transducers or as optical or electroactive labels to improve different aspects of performance, for example sensitivity, detection limit, multidetection capability, and response stability. Nanoparticles can be integrated into the transducer materials on an individual basis or inside other matrices to ensure the immobilization of recognition biomolecules and/or receptors which are the principal components of the (bio)sensing systems.
View Article and Find Full Text PDFA novel visualization methodology based on the use of immunofluorescence and Confocal Laser Scanning Microscopy (CLSM) was used to quantify and visualize tyrosinase enzyme within a MWCNTs matrix immobilized onto carbon based screen-printed electrodes. CLSM was shown to be an extremely powerful technique which allowed a clear visualization of the distribution of the enzyme within both the MWCNTs and carbon based layers and provided additional and useful morphological data for a better understanding of the interaction between biomolecules and electrode materials. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) were also employed to fully characterize the system components.
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