An Aptamer-Nanogold Probe for Trace PDGF Using Resonance Rayleigh Scattering as Detection Technique

Abstract

The aptamer of platelet-derived growth factor (PDGF) was used to modified nanogold to obtain a stable aptamer-nanogold(Apt-NG) probe for PDGF. In the condition of pH 7.2 Na2HPO4-NaH2PO4 buffer solution and 5.33 mmol/L NaCl, the Apt-NG specifically combined with PDGF to form Apt-NG-PDGFA cluster that resulted in the resonance Rayleigh scattering (RRS) intensity at 550 nm. When the PDGF concentration increased, the nanogold aggregated (NGA) increased, and the RRS intensity at 550 nm increased. The increased RRS intensity ΔI550nm was linear to the PDGF concentration in the range of 3.33-40 ng/mL, with a regression equation of ΔI550nm=10.8 C-24.2, coefficient of 0.9932 and a detection limit of 0.53 ng/mL