抄録
Gold nanoplates were prepared in high yield at room temperature using the Fe(III)-reducing bacterium Shewanella algae. The cell extract, prepared by sonicating a suspension of S. algae cells, plays an important role in improving productivity of gold nanoplates. S. algae cell extract was capable of reducing aqueous AuCl4- ions into elemental gold within 60 min when H2 gas was provided as an electron donor. Gold nanoplates with an edge length of 100 nm appeared after 6 hours, and compact gold nanoplates with an edge length of 100-200 nm were obtained after 24 hours. The prepared nanoplates had diffraction spots characteristic of single-crystalline (111)-oriented gold nanocrystal. Using S. algae cell extract, the yield of gold nanoplates relative to the total nanoparticle population was 60 %, which was four times higher than that obtained with a suspension of resting cells. Following centrifugal ultrafiltration of the S. algae extract, only the fraction containing biomolecules greater than 50 kDa successfully produced gold nanoplates.
