Biotin functionalized gold nanoparticles are suitable for binding of streptavidin labelled conjugates. The gold nanoparticle label allows for straightforward detection of streptavidin by measuring the increase in absorbance of the sample upon binding. The absorption maximum is gold nanoparticle size dependent and ranges from 515-520nm for a 5nm particle to 572nm for a 100nm particle.
Gold nanoparticles 20 nm diameter, biotin terminated, PEG 5000 coated, OD 50, dispersion in H2O can be used as a theranostic agent for potential usage in cancer therapy and treatment of COVID-19. It can also be used in the detection of pathogens for biosensing applications. AuNPs may be used to prepare SARS-CoV-2 conjugate for COVID-19 detection using lateral flow immunoassay technique.