抗冻剂抗冻机制的近红外光谱与分子模拟研究

Antifreeze Mechanism of Antifreeze Agents by Near Infrared Spectroscopy and Molecular Simulations

抗冻剂在生物样品的冷冻保存中广泛使用,生物体为抵御冻害产生抗冻蛋白,因此,抗冻机制研究一直备受关注.抗冻剂通过与水/冰晶发生相互作用,使体系的冰点降低并抑制体系中冰晶的形成.水结构对温度变化非常敏感,结合温控近红外光谱技术和化学计量学方法,利用随温度变化的水光谱信息,研究了低温环境下水的结构以及抗冻剂与水/冰晶之间产生的相互作用,在分子层面上认识了抗冻剂的抗冻机制.利用分子动力学模拟考察了原子尺度上抗冻剂与水/冰晶相互作用的细节,并与光谱实验手段结合揭示了抗冻剂的抗冻机制.本文概述了抗冻剂抗冻机制的研究进展,总结了温控近红外光谱及分子动力学模拟在抗冻剂与水/冰晶之间相互作用研究的工作进展,旨在为抗冻剂抗冻机制研究提供新的思路.

Cryopreservation is an essential technology for long-term storage of organs,tissues,cells and other biological samples.During cryopreservation,antifreeze agents are commonly used to reduce the freezing point of the system and inhibit the formation of ice crystals(ice nucleation,ice growth,and ice crystal recrystallization),thereby avoiding damage to biological samples caused by uncontrolled ice formation at low temperature.However,due to the difficulty in obtaining microscopic details of the interaction between antifreeze agents and water/ice in experiment,the mechanism of antifreeze has not yet been clearly understood.The hydrogen-bonded structure of water is very sensitive to temperature changes.By combining temperature-dependent near-infrared spectroscopy(NIRS)and chemometric methods,the hydrogen-bonded structure of water in low-temperature environments and the interactions between antifreeze agents and water/ice crystals are studied.The antifreeze mechanisms are understood at the molecular level using spectral information of water that changes with temperature.The details of the interaction between antifreeze agents and water/ice crystals at the atomic level are investigated using molecular dynamics(MD)simulation,and the antifreeze mechanisms are revealed by combining spectroscopic experimental methods.This Account provides an overview of the research progress on the antifreeze mechanism of antifreeze agents,with a focus on the recent advances in the study of the interaction between antifreeze agents and water/ice crystals using temperature-dependent NIRS and MD simulations.Overall,the Account aims to provide new ideas for the study of antifreeze mechanisms and deepen our understanding of the molecular details of the antifreeze mechanism.Finally,the challenges and prospects of using NIRS to reveal the antifreeze mechanism of antifreeze agents are discussed and possible further improvements are proposed,such as developing more effective chemometric methods to extract the spectral information of water molecules with different hydrogen-bonded structures from the NIRS of water,introducing importance sampling technique specially designed for water icing into MD simulations to enhance the sampling efficiency,so that MD simulations can be used to explore the entire process of water freezing inhibition by antifreeze agents,deepening the understanding of the antifreeze mechanism.