ABSTRACT
Objective To assess the function of the peptide (WHGSLKQNLWWY) through measuring the a functional affinity constant between humanized VEGF receptor 3 and peptide, then comparing it to that between VEGF D and peptide. Methods After coating the peptide by BSA binding with glutaral couple, the best concentration, best time of peptide to coat the plate and the coating coefficient were determined. With cognizance of the advantages of solid phase method in time consumption and convenience, we assessed the functional affinity constant of engineered peptide and VEGF-D with non-competitive ELISA method. We plotted the D(410) standard curve of the binding reaction of peptide and VEGFR3/Fc using four grades of concentration of VEGFR3/Fc and a series of consistency of peptide. We got the consistency of peptide at the half of maximal OD value through the standard curve and calculated the affinity constant by law of Mass Action. Results The affinity constant of peptide was between 10 7-10 8 mol/L -1, which was only smaller by 10 times than that of VEGF-D. Conclusion The peptide we got from the peptide liberary can strongly bind to the target (VEGFR3), thus providing a theoretical basis for its pharmacal use.