Quantum dot-based electrochemical DNA biosensor using a screen-printed graphite surface with embedded bismuth precursor

摘要: Abstract This work reports the development of screen-printed quantum dots (QDs)-based DNA biosensors utilizing graphite electrodes with embedded bismuth citrate as a precursor. The sensor surface serves both support for immobilization oligonucleotide and an ultrasensitive voltammetric QDs transducer relying on nanoparticles. utility this biosensor is demonstrated detection C634R mutation through hybridization biotin-tagged target surface-confined capture complementary probe subsequent reaction streptavidin-conjugated PbS QDs. electrochemical transduction step involved anodic stripping determination Pb(II) released after acidic dissolution Simultaneously electrolytic accumulation Pb surface, was converted in situ to nanoparticles enabling ultra-trace determination. showed linear relationship peak current respect logarithm concentrations from 0.1 pmol L − 1 10 nmol L , limit 0.03 pmol . exhibited effective discrimination between single-base mismatched sequence fully DNA. These “green” are inexpensive, lend themselves easy mass production, hold promise bioassay formats.