Dengue NS1 antigen detection using photoluminescence of solution phase biotylinated anti-NS1 antibody conjugated ZnO quantum dots

Biotinylated anti-NS1 antibody of dengue was conjugated on the streptavidin functionalized ZnO quantum dots (QD) by EDC-NHS chemistry. Photoluminescence spectra of the ZnO QDs showed band edge peak (∼366 nm, peak 1) and a defect related peak (∼470 nm, peak 2). The defect related peak was present only for Zn/Li ratio below 0.5. The change in the luminescence intensity of peak 1 and peak 2 was studied with negative and positive serum of suspected dengue cases. A 14% decrease of the average intensity of peak 1 and peak 2 was observed per 20 μl addition of negative serum. In the case of dengue positive serum, the average intensity was increased by 7% per 20 μl of serum sample. This suggests that the prepared solution phase ZnO QDs could be applied in the detection of dengue antigen in suspected patients’ serum.