A cost-effective and eco-friendly click biosynthesis of small molecule quercetin–gold quantum dots (QRT–AuQDs) was developed involving quick conjugation, using an ultrasonication method at ambient temperature by utilizing QRT and gold ions in the molar ratio 0.1 : 1.

This technique to be advantageous: gold recovery from bio-waste of COVID-19 & similar kits. Forensic investigations, gold jewelry makers & related industries to benefit from the proposed gold recycling process & contribute to socio-economic growth.