title: Studies on interaction of CdTe quantum dots with bovine serum albumin using fluorescence correlation spectroscopy.
abstract: Luminescent quantum dots (QDs) have widely used in some biological and biomedical fields due to their unique and fascinating optical properties, meanwhile the interaction of QDs with biomolecules recently attract increasing attention. In this paper, we employed fluorescence correlation spectroscopy (FCS) to investigate the nonspecific interaction between CdTe QDs and bovine serum albumin (BSA) as a model, and evaluate their stoichiometric ratio and association constant. Our results documented that BSA was able to bind to CdTe QDs and form the QD-BSA complex by a 1:1 stoichiometric ratio. The association constant evaluated is 1.06+/-0.14x10(7) M(-1) in 0.01 M phosphate buffer (pH=7.4). Furthermore, we found that QD-BSA complex dissociated with increase of ion strength, and we speculated that the interaction of CdTe QDs with BSA was mainly attributed to electrostatic attraction. Our preliminary results demonstrate that fluorescence correlation spectroscopy is an effective tool for investigation of the interaction between quantum dots (or nanoparticles) and biomolecules.
authors.affiliation: College of Chemistry and Chemical Engineering, Shanghai Jiaotong University, 800 Dongchuan Road, Shanghai, 200240, People's Republic of China.
authors.forename: Liwen
authors.initials: L
authors.lastname: Shao
authors.forename: Chaoqing
authors.initials: C
authors.lastname: Dong
authors.forename: Fuming
authors.initials: F
authors.lastname: Sang
authors.forename: Huifeng
authors.initials: H
authors.lastname: Qian
authors.forename: Jicun
authors.initials: J
authors.lastname: Ren
mesh_terms: D019187:Cadmium Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D008163:Luminescent Measurements / Q000379:methods; D009994:Osmolar Concentration; D045663:Quantum Dots; D012680:Sensitivity and Specificity; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D013050:Spectrometry, Fluorescence / Q000379:methods; D013691:Tellurium / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D012710:Serum Albumin, Bovine; D012965:Sodium Chloride; D013691:Tellurium; C028337:cadmium telluride