文献类型：期刊文献

英文题名：Adsorption Kinetics of Biosurfactant Surfactin at the n-Hexadecane/Aqueous Solution Interface

作者：Gang, Hong-ze[1,2,3];Wu, Qing-ying[1,2];Yang, Zhi-yuan[1,2];Su, Zhi-qing[4];Li, Ying-cheng[4];Yang, Shi-zhong[1,2,3];Mu, Bo-Zhong[1,2,3]

机构：[1]East China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem & Mol Engn, Shanghai 200237, Peoples R China;[3]East China Univ Sci & Technol, Engn Res Ctr Microbial Enhanced Oil Recovery, MOE, Shanghai 200237, Peoples R China;[4]Sinopec Shanghai Res Inst Petrochem Technol, Sinopec Key Lab Surfactants EOR, Shanghai 201208, Peoples R China

年份：2023

卷号：127

期号：16

起止页码：3728

外文期刊名：JOURNAL OF PHYSICAL CHEMISTRY B

收录：;EI(收录号：20231613903202);WOS:【SCI-EXPANDED(收录号:WOS:000971999500001)】；

基金：This research was supported by funding from National Key Research and Development Program of China (no. 2022YFC2105200) . We thank Dr. J. Liao for the helpful discussion of mathematical fitting.

语种：英文

外文关键词：Adsorption - Biomolecules - Micelles - Molecular dynamics - Paraffins - Rate constants

摘要：Surfactin is a typical kind of biosurfactant with a large diversity of structure, and its molecular structure is expected to play a crucial role in its adsorption dynamics. Adsorption kinetics of surfactin homologues at the n-hexadecane/aqueous solution interface is studied using a droplet-based microfluidic method. Molecular dynamics simulations are performed to illustrate the dependence of adsorption energy on the surfactin structure. Rapid reduction of dynamic interfacial tensions is obtained. The best fit to experimental results reveals that surfactin with shorter aliphatic chains, C13-surfactin and C14-surfactin, has larger rate constants of adsorption and desorption. Interfacial tensions are rapidly reduced in the case of the oil/water interface which is freshly formed, and the equilibrium adsorption is rapidly established approximately in 100-350 ms at concentrations above the critical micelle concentration. C15-surfactin that has a longer aliphatic chain adsorbs and desorbs slower, and the equilibration time of adsorption is slightly longer. Moreover, C15-surfactin has a strong tendency for adsorbing at the interface, which is in accordance with the larger adsorption energy obtained by molecular dynamics simulation, and aggregating behavior in solution. The present study provides insights on the surfactin structure and the dynamics of adsorption at the liquid/liquid interface.