Simple and effective:Superlubricity behaviour of the G-quadruplex hydrogel with high selectivity for K^(+) ions based on the ocular environment  

作　　者：Hongdong WANG Jian WU Kunpeng WANG Yunjuan SU Xiacong ZHANG Yuhong LIU Jianhua ZHANG 

机构地区：[1]School of Mechatronic Engineering and Automation and Key Laboratory of Advanced Display and System Application,Ministry of Education,Shanghai University,Shanghai 200444,China [2]State Key Laboratory of Tribology in Advanced Equipment,Tsinghua University,Beijing 100084,China [3]Department of Polymer Materials,School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China

出　　处：《Friction》2024年第11期2548-2562,共15页摩擦（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.52275203 and 52105194);China Postdoctoral Science Special Funding Project(Grant No.2022T150353);the Tribology Science Fund of State Key Laboratory of Tribology in Advanced Equipment(Grant Nos.SKLTKF20A01 and SKLTKF23A04).

摘　　要：Hydrogels have been the subject of significant research in the field of friction due to their exceptional lubricating properties.In this study,the G-quadruplex hydrogel with high selectivity for K^(+) ions was formed by introducing a mixture of G,2-formylphenylboronic acid,and polyethylene glycol diamine into simulated artificial tears solution with high transparency,and an ultra-low coefficient of friction(COF)of about 0.004 was obtained based on the simulated ocular environment,thus achieving macroscopic superlubricity.In friction pairs simulating the ocular environment,to assess the frictional performance of the G-quadruplex hydrogel as both a lubricant and a friction pair based on the simulated ocular environment,we conducted experiments considering various factors such as concentration,sliding speed,and stress.Through these experiments,it was found that superlubricity was achieved when the G-quadruplex hydrogel was applied as lubricant or friction pair.This effect was attributed to the three-dimensional network structure and hydrophilicity of the hydrogel,which facilitated the formation of a highly bearing and flowing hydration layer,promoting macroscopic superlubricity.Compared to the G-quadruplex hydrogel with low concentration,the high concentration hydrogel(75 mM)exhibited increased mechanical strength and robustness in superlubricity.Combined with biocompatibility experiments,our synthesized G-quadruplex hydrogel has excellent biocompatibility and offers a novel approach to achieve superlubricity in ocular drug delivery.

关 键 词：SUPERLUBRICITY ocular environment G-quadruplex hydrogel bio-compatibility 

分 类 号：TH117[机械工程—机械设计及理论]