Hart D E, DePaolis M, Ratner B D, Mateo N B
Department of Ophthalmology, College of Physicians and Surgeons, Columbia University, New York, NY.
CLAO J. 1993 Jul;19(3):169-73.
We used electron spectroscopy for chemical analysis (ESCA) to examine the surface chemistry of polymacon, tefilcon, and bufilcon hydrogel contact lenses. Worn and unworn water-cleaned and surfactant-cleaned lenses were compared. The surface chemistry of unworn lenses, which were used as controls, consisted of approximately 70% carbon, 25% oxygen, and < 10% other elements (i.e., silicon, sulfur, sodium, nitrogen, and zinc). In general, surfactant cleaning removed silicon contamination, but left a residue containing sulfur and zinc. The increase in the nitrogen/carbon (N/C) ratio for worn bufilcon and polymacon lenses was significantly greater than the N/C ratio for unworn bufilcon and polymacon lenses. As a group the worn ionic lenses (bufilcon) showed a greater N/C ratio than the worn nonionic lenses (polymacon, tefilcon). The nitrogen that appears on all worn lenses probably represents adherent as well as adsorbed surface proteins. The highest N/C ratios were found on a pair of pathologically deposited lenses and on the lens with the longest wearing time (2 years). For the bufilcon and polymacon lenses, the differences observed in the ESCA data for the unworn and worn lenses suggest that contact lenses begin interacting with the tear film within 1 minute (the shortest wearing time in this study).
我们使用化学分析电子能谱法（ESCA）来检测聚甲基丙烯酸羟乙酯、甲基丙烯酸羟乙酯和甲基丙烯酸丁酯水凝胶隐形眼镜的表面化学性质。对佩戴过和未佩戴过的经水清洗和表面活性剂清洗的镜片进行了比较。用作对照的未佩戴过的镜片，其表面化学组成约为70%的碳、25%的氧以及<10%的其他元素（即硅、硫、钠、氮和锌）。一般来说，表面活性剂清洗去除了硅污染，但留下了含有硫和锌的残留物。佩戴过的甲基丙烯酸丁酯和聚甲基丙烯酸羟乙酯镜片的氮/碳（N/C）比值增加显著大于未佩戴过的甲基丙烯酸丁酯和聚甲基丙烯酸羟乙酯镜片的N/C比值。作为一个整体，佩戴过的离子型镜片（甲基丙烯酸丁酯）的N/C比值高于佩戴过的非离子型镜片（聚甲基丙烯酸羟乙酯、甲基丙烯酸羟乙酯）。所有佩戴过的镜片上出现的氮可能代表附着以及吸附在表面的蛋白质。在一副有病理沉积物的镜片和佩戴时间最长（2年）的镜片上发现了最高的N/C比值。对于甲基丙烯酸丁酯和聚甲基丙烯酸羟乙酯镜片，未佩戴和佩戴过的镜片在ESCA数据中观察到的差异表明，隐形眼镜在1分钟内（本研究中最短的佩戴时间）就开始与泪膜相互作用。
