探討甲基丙烯酸羥乙酯與甲基丙烯酸共聚物水膠作為隱形眼鏡材料之特性

Abstract

本研究旨在探討不同hydroxyethyl methacrylate (HEMA)與methacrylic acid (MAA)組成比例對於其共聚物水膠特性之影響，本研究中一共聚合三種不同重量百分比之HEMA:MAA單體溶液(98.8:0、96.8:2、93.8:4.9)，經由UV光照射聚合後形成水膠。本研究中所探討之水膠特性包含：表面疏水性、飽和含水率、表面粗糙度、透光率，以及膠體在溶菌酶溶液中，對於溶菌酶之吸附和後續之脫附。自膠體脫附後的溶菌酶，其結構也以多種光譜及實驗方法檢驗。除此之外，格蘭氏陰性(大腸桿菌)及陽性菌(金黃色葡萄球菌)於膠體表面貼附之行為亦在本研究之探討範圍中。以HEMA-co-MAA水膠作為模型材料，我們希望得以觀察MAA之添加對於膠體特性之影響，並了解其中之機制。

The purpose of this work was to investigate the relationship between the feed composition of 2-hydroxyethyl methacrylate (HEMA)/methacrylic acid (MAA) and the characteristics of the resultant hydrogel material. The monomer solutions of HEMA and MAA were mixed at different weight ratios of 98.8:0, 96.8:2, 93.8:4.9, 89:9.9, and 79.1:19.8, and were subjected to UV irradiation. Properties including surface hydrophobicity (by water contact angles), equilibrium water content (EWC), mean surface roughness (by AFM), and transparency (by UV/Vis-absorption spectrometer) were studied on these hydrogels. When the gel was soaked in DI water, the EWC was observed to be in the range of 30-40%. However, a significantly higher EWC (~60%) was perceived upon soaking in PBS. Our results indicated that the addition of hydrophilic MAA lead to a reduction in water contact angle, showing a negative correlation between the amount of MAA and surface hydrophobicity. Also, the addition of MAA was found to increase the mean surface roughness and surface energy, both are related to the decrease in hydrophobicity. Almost no difference was detected in the transparency of hydrogels soaked in DI water and PBS except for the latter exhibiting a rapid rise near the wavelength of 200 nm. In addition, the adsorption and desorption behaviors of a model protein, lysozyme, on the hydrogels were examined. The result indicated that the addition of MAA would increase lysozyme adsorption but the lysozyme desorption was decreased. We believe the result of this work may aid in the development and improvement of the materials used for soft contact lenses.