Au nanoparticles (AuNPs) have good absorption properties in the visible region, while upconversion nanoparticles (UCNPs) have an emission at 547 nm upon excitation with a 980 nm laser, which could avoid most interfering signals of biomolecules in serum. In this paper, we developed an aptasensor for platelet-derived growth factor (PDGF–BB) detection in 30% blood serum based on fluorescence resonance energy transfer between AuNPs and UCNPs. With the proposed aptasensor, PDGF–BB in 30% blood serum was detected. Two consecutive linear ranges allow a wide determination of PDGF–BB concentrations with a low detection limit of 10 nM (S/N = 3). Importantly, the fluorescence biosensor can directly detect PDGF–BB in blood serum of lymphoma patient. This detection approach can also exhibit good stability and selectivity.
