Bacterial Synthesis of Cadmium and Zinc Sulfide Nanoparticles: Characteristics and Prospects of Application

Abstract

Nanoparticles of cadmium sulfide (NpCdS) and zinc sulfide (NpZnS) are shown to be formed in the presence of Shewanella oneidensis MR-1 bacteria. These nanoparticles were located in the culture liquid and had a spherical shape. The nanoparticles were characterized by a small range of size distribution; the maximal size of NpCdS and NpZnS was approximately 5–6 nm; over 70% of the nanoparticles had a size of approximately 2–4 nm. The effective diameter of NpCdS and NpZnS was 158.9 nm and 219.3 nm, respectively. The value of the ζ-potential of NpCdS and NpZnS was –22.43 and –31.46 mV, respectively, which characterized the aqueous suspensions of these nanoparticles as metastable. The selectivity of the adsorption of certain proteins from the common pool of the protein molecules, synthesized by S. oneidensis MR-1 strain during cultivation, on the surface of nanoparticles is ascertained. Independently of the chemical nature of the particles (NpCdS and NpZnS), the protein molecules adsorbed on their surface are shown to have similar molecular weights. For the first time, biogenic NpCdS and NpZnS are used to develop a model composite system by the immobilization of amine-containing poly(glycidyl methacrylate) (PGMA) microspheres on the surface.