title: Spectroscopic studies of bovine serum albumin adsorbed onto magnetic-thermosensitive carbon microspheres.
abstract: To investigate the influence of magnetic-thermosensitive carbon microspheres (MTCMSs) as a targeting drug carrier on serum albumins in vitro, in this study, bovine serum albumin (BSA) was chosen as a template protein to explore the interaction between serum proteins and MTCMSs. Fluorescence spectrophotometry, ultraviolet-visible absorbance (UV-vis) spectrophotometry and circular dichroism spectrometry were used to investigate the interaction between MTCMSs and BSA. Results indicate that BSA interacts with MTCMSs and the fluorescence intensity of BSA is quenched by 50% in a static quenching at 310 K when the concentration of MTCMSs reaches 30 mg/L. Thermodynamic parameters including free energy change (△Gθ), enthalpy change (△Hθ) and entropy change (△Sθ) were calculated. The results (△Gθ< 0, △Hθ< 0 and △Sθ> 0) suggest a spontaneous process and the formation of a hydrogen bond between MTCMSs and BSA. UV-vis measurements reveal that the micro-environment of an amino acid residue is altered in the presence of MTCMSs. The α-helix content of BSA decreases by 4% and the β-sheet content increases by 3.2% with increasing concentrations of MTCMSs to 30 mg/L, illustrating a change in the skeletal structure of BSA. These results demonstrate that MTCMSs as a targeting drug carrier impact the structure of serum albumins. This work provides not only a theoretical basis of BSA adsorption onto MTCMSs, but also an understanding of safe drug carriers in biomedicine. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, 030024, China.|College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, 030024, China.|Research Center on Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan, 030024, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.affiliation: Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, 030024, China.|Research Center on Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan, 030024, China.
authors.forename: Longfei
authors.initials: L
authors.lastname: Li
authors.affiliation: Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, 030024, China.|Research Center on Advanced Materials Science and Technology, Taiyuan University of Technology, Taiyuan, 030024, China.
authors.forename: Yongzhen
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Key Laboratory of Interface Science and Engineering in Advanced Materials, Taiyuan University of Technology, Ministry of Education, Taiyuan, 030024, China.|College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan, 030024, China.
authors.forename: Xuguang
authors.initials: X
authors.lastname: Liu
mesh_terms: D000327:Adsorption; D000818:Animals; D002244:Carbon / Q000737:chemistry*; D002417:Cattle; D008280:Magnetics; D008863:Microspheres; D012710:Serum Albumin, Bovine / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013696:Temperature; D013816:Thermodynamics
chemical_list: D012710:Serum Albumin, Bovine; D002244:Carbon
keywords: bovine serum albumin; interaction; magnetic-thermosensitive carbon microspheres; spectroscopy