Nanomaterials are increasingly applied in our lives in recent years. However, the high cost and complicated fabrication procedures of nanomaterials are the major barriers to their widespread application. Biofabrication offers new opportunities due to its distinct advantages over conventional chemical synthesis route, but the process controllability and efficiency still need to be improved. The research group of Prof. Han-Qing Yu and Prof. Wen-Wei Li from the CAS Key Laboratory of Urban Pollutant Conversion collaorated to develop a new strategy for regulating the biofabrication process. A directed production of cadmium selenide fluorescent nanoparticles in microbial cells, with fine-tuned composition and subcellular synthetic location, was achieved by utilizing the inherent cellular detoxification mechanism. The results were published in J. Am. Chem. Soc., 2017, 139, 12149−12152. In this work, the detected by the Se K-edge X-ray absorption near-edge structure (XANES) and extended X-ray and absorption fine structure (EXAFS) spectroscopy (from National Synchrotron Radiation Laboratory) were used to identify the composition and spatial distribution of the biofabricated nano-materials in vivo. It provides key evidences for understanding the Se transformation and Se-Cd interaction processes inside the cells.

Pathway of directed biosynthesis of CdSe nanoparticles