Biomimetic synthesis of HgS nanoparticles in the bovine serum albumin solution

HgS nanocrystals conjugated with protein were synthesized in aqueous solution of Bovine Serum Albumin (BSA) at room temperature. The obtained HgS nanoparticles with average diameter about 20-40 nm were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), selected-area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM). The quantum-confined effect of the HgS nanoparticles is confirmed by the ultraviolet-visible (UV-vis) and photoluminescence (PL) spectrum. The rescults indicate that the BSA not only induce the nucleation, but inhibit the further growth of HgS nanoparticles. The effect of Hg2+ on BSA and the change of BSA conformation were studied through Fourier transform infrared (FTIR) spectroscopy and Circular dichroism (CD) spectroscopy. The possible mechanism of HgS nanoparticles growth in the BSA solution was also discussed.