Fast functionalization of silver decahedral nanoparticles with aptamers for colorimetric detection of human platelet-derived growth factor-BB.

Abstract Aptamer-silver decahedral nanoparticles (Ag 10 NPs-aptamer) based detection was developed for protein. Ag 10 NPs were synthesized by photochemical method. The advantage of Ag 10 NPs was its tolerance of NaCl which facilitates the functionalization of silver nanoparticles with all kinds of ssDNA. Attaching aptamers to Ag 10 NPs could be achieved within 2 h, much faster than traditional methods. Human platelet-derived growth factor-BB (PDGF-BB) was used as a model protein to test the binding capacity of aptamers attached on Ag 10 NPs. Our data showed that the aptamer-Ag 10 NPs conjugates were successful in detecting human PDGF-BB. Furthermore, we developed an aptamer-Ag 10 NPs conjugates-based colorimetric sensor to detect PDGF-BB. The results showed a linear relationship between PDGF-BB concentrations (5 ng mL −1 –200 ng mL −1 ) and ΔOD with excellent detection specificity in serum. Therefore, the sensor based on aptamer-Ag 10 NPs conjugates was highly effective and sensitive and had great promise for further development and applications.