Biocompatible bovine serum albumin stabilized platinum nanoparticles for the oxidation of morin

Abstract

The development of monodisperse platinum nanoparticles with high biocompatibility for organic dye treatment has been drawing great interest. Herein, bovine serum albumin (BSA) was used to stabilize different platinum nanoparticles (Pt_n@BSA NPs, n = 10, 15, and 20), where the Pt metal precursor (K₂PtCl₄) was incubated with BSA solution, followed by the addition of excess NaBH₄ as a reducing agent. The prepared Pt_n@BSA NPs had small size with a narrow distribution. They also showed good catalytic activity towards morin. Transmission electron microscopy (TEM) images demonstrated that the average sizes of Pt₁₀@BSA, Pt₁₅@BSA and Pt₂₀@BSA were 1.70 ± 0.39, 2.15 ± 0.42 and 3.11 ± 0.72 nm, respectively. Dynamic light scattering (DLS) results showed that the hydrodynamic sizes of Pt₁₀@BSA, Pt₁₅@BSA and Pt₂₀@BSA were 4.25, 6.57 and 8.84 nm, and the corresponding zeta potentials were −31.23, −30.20 and −29.77 mV, respectively. In addition, the oxidation of morin using Pt_n@BSA NPs followed a pseudo-first-order reaction in the presence of H₂O₂. The apparent rate constant K_app was dependent on the concentration of Pt_n@BSA NPs, morin and H₂O₂. Pt_n@BSA NPs expedited the formation of hydroxyl radicals (˙OH) from H₂O₂. More importantly, Pt_n@BSA NPs were highly biocompatible towards HeLa cells. Taken together, Pt_n@BSA could be employed as an eco-friendly catalyst to treat organic dyes in the future.