Noble Metal Nanoparticles Synthesis Mediated by the Genus Dolichospermum: Perspective of Green Approach in the Nanoparticles Preparation

Regarding the rapid development of the nanotechnology a growing interest in applications of metal nanoparticles such as silver (Ag) and gold (Au) is obvious. These metals in the nanoform may be prepared by an economically and environmentally efficient way called biosynthesis. Metal nanoparticles may be prepared via biosynthesis in the form of suspensions or colloid solutions. Moreover, suspensions may be dried into the powder form. So called bionanocomposites contain (micro)organisms cells with attached nanoparticles. The nanocomposites may be used directly e.g., in heterogeneous catalysis. Recently, nanosilver and nanogold often find an application in the medicine as antimicrobial agents. In this work, we would like to present a simple experiment of silver and gold nanoparticle preparation using cells of the genus Dolichospermum. Resulting silver nanoparticles were approximately 10 nm in size and well stabilized by excreted biomolecules in the solution. Gold nanoparticles disposed of 23 nm in size and they are homogeneously dispersed. Transmission electron microscopy (TEM) and selected area electron diffraction (SAED) were main techniques used for the evaluation of the morphology and crystallography of the nanoparticles.