Ultralow detection of 3,4-methylenedioxymethylamphetamine using an immunofluorescence nanoconjugate of heavy metal-free alloyed quantum dots and NiCeFe3O4 magnetic nanoparticles

The recreational use of 3,4-methyl​enedioxy​methylamphetamine (MDMA) remains consistently high on a global level. This reinforces the importance early, rapid and accurate detection MDMA. work reports novel development rapid, ultrasensitive selective immunofluorescence nanobiosensor probe for To develop nanoprobe, heavy metal-free AuZnFeSeS alloyed quantum dots (QDs) were synthesized coated with carboxy (COOH)-silica subsequently conjugated to an anti-MDMA antibody (Ab). Secondly, spinel NiCeFe3O4 magnetic nanoparticles (MNPs) synthesized, surface functionalized L-cysteine same Ab. An immunocomplex was established where both QDs-Ab NiCeFe3O4-Ab each captured target MDMA drug. bound QDs fluorescently reported biomolecular interaction between nanomaterials Ab while MNPs functioned as adsorbent signal amplifier. binding switched off fluorescence but upon NiCeFe3O4-Ab, on. Experimental analysis revealed inefficiency (without NiCeFe3O4-Ab) detect ultrasensitively selectively; hence, justified in system. Under optimum reaction conditions, quantitatively detected using QDs-Ab-NiCeFe3O4-Ab nanocomplex concentration range 0.05–50,000 nM limit 0.02 (0.0046 ng/mL) obtained. developed nanoprobe successfully used urine satisfactory recoveries.