Bioconjugation of quantum dots (QDs) provide high resolution in biological fluorescent labelling as a result of physical and optical properties of QDs. This intrinsic property of QDs can be made use of for sensitive detection of target analytes including food and environmental monitoring. In this investigation, we report the bioconjugation of thiol stabilized CdTe QD for the sensitive detection of methyl parathion (MP) at picogram level. The specificity in the analysis was attributed by highly specific competitive immunological reactions between free MP and CdTe QD bioconjugated MP (MP-BSA-CdTe) for immobilized anti-MP IgY antibodies in a simple flow injection system. We also report the possible resonance energy transfer phenomenon as a result of nanobiomolecular interaction obtained through the bioconjugation of CdTe QD with protein bovine serum albumin (BSA). This has resulted in a significant change in the photo-absorption of CdTe QD, which can be made use for future nanosensor development
