title: Bovine serum albumin-directed synthesis of biocompatible CdSe quantum dots and bacteria labeling.
abstract: A simple method was developed for preparing CdSe quantum dots (QDs) using a common protein (bovine serum albumin (BSA)) to sequester QD precursors (Cd(2+)) in situ. Fluorescence (FL) and absorption spectra showed that the chelating time between BSA and Cd(2+), the molar ratio of BSA/Cd(2+), temperature, and pH are the crucial factors for the quality of QDs. The average QD particle size was estimated to be about 5 nm, determined by high-resolution transmission electron microscopy. With FL spectra, Fourier transform infrared spectra, and thermogravimetric analysis, an interesting mechanism was discussed for the formation of the BSA-CdSe QDs. The results indicate that there might be conjugated bonds between CdSe QDs and -OH, -NH, and -SH groups in BSA. In addition, fluorescence imaging suggests that the QDs we designed can successfully label Escherichia coli cells, which gives us a great opportunity to develop biocompatible tools to label bacteria cells.
authors.affiliation: State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, People's Republic of China.
authors.forename: Qisui
authors.initials: Q
authors.lastname: Wang
authors.forename: Fangyun
authors.initials: F
authors.lastname: Ye
authors.forename: Tingting
authors.initials: T
authors.lastname: Fang
authors.forename: Wenhan
authors.initials: W
authors.lastname: Niu
authors.forename: Peng
authors.initials: P
authors.lastname: Liu
authors.forename: Xinmin
authors.initials: X
authors.lastname: Min
authors.forename: Xi
authors.initials: X
authors.lastname: Li
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D002104:Cadmium / Q000737:chemistry*; D002417:Cattle; D004926:Escherichia coli; D005453:Fluorescence; D006863:Hydrogen-Ion Concentration; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D045663:Quantum Dots; D012643:Selenium / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013194:Staining and Labeling / Q000379:methods*; D013696:Temperature
chemical_list: D001672:Biocompatible Materials; D002104:Cadmium; D012710:Serum Albumin, Bovine; D012643:Selenium