Fiber optic surface plasmon resonance biosensor for detection of PDGF-BB in serum based on self-assembled aptamer and antifouling peptide monolayer

Herein, a home-build fiber optic surface plasmon resonance (FO-SPR) biosensing platform has been developed for highly sensitive detection of platelet-derived growth factor (PDGF-BB) based aptamer-functionalized AuNPs for signal enhancement. In this biosensor, the PDGF-BB aptamer was used to specifically capture PDGF-BB, and the antifouling peptide demonstrated great ability for resisting non-specific adsorption. After a sandwich reaction, the aptamer, PDGF-BB and aptamer-functionalized AuNPs complexes were formed on the fiber optic (FO) probe surface to significantly amplify FO-SPR signal. This method exhibited a broad detection range from 1 to 1000 pM of PDGF-BB and a low detection limit of 0.35 pM. Moreover, this biosensor was successfully applied to the detection of PDGF-BB in 10% human serum samples without suffering from serious interference owing to the excellent antifouling property of the peptide. Thus, this developed FO-SPR biosensor could be a potential alternative device for proteins determination, even as a point-of-care diagnostic tool (POCT) in clinical application.