Upconversion fluorescence resonance energy transfer biosensor for sensitive detection of human immunodeficiency virus antibodies in human serum.

A facile one-step approach was proposed to prepare hydrophilic and peptide-functionalized upconversion nanoparticles (UCNPs), which were used in the design of a biosensor for the sensitive and selective determination of human immunodeficiency virus antibodies in human serum based on FRET from the UCNPs to the graphene oxide.