UV photochemical synthesis of heparin-coated gold nanoparticles

Sodium salt heparins of both reactive and pharmaceutical grade were used as the reducing and stabilizing agents for the UV photochemical synthesis of gold nanoparticles. Reduction of chloroauric acid, HAuCl4, by heparin using UV irradiation as a catalyst is a simple, inexpensive method with direct biofunctionalization of the products for further use. Experiments using both heparin types were carried out separately. The varying synthesis parameters were the HAuCl4 and heparin sodium concentrations. The synthesized AuNPs present spherical as well as anisotropic shapes, such as oval, triangular, hexagonal sheets, rods, and some other faceted forms, with dimensions ranging from 20 to 300 nm as well as agglomerated networks. No usage of additional surfactants or growth-inducing seeds was necessary in the syntheses.