泪液脂质界面流变学：溶菌酶和隐形眼镜护理液的影响
Tear lipids interfacial rheology: effect of lysozyme and lens care solutions.
作者信息
Svitova Tatyana F, Lin Meng C
机构信息
Clinical Research Center, University of California, Berkeley, California 34720-2020, USA.
出版信息
Optom Vis Sci. 2010 Jan;87(1):10-20. doi: 10.1097/OPX.0b013e3181c07908.
PURPOSE
To evaluate the interfacial properties of ex vivo tear lipid multilayers with controlled and varying thickness. The influence of lysozyme and surfactant-containing multipurpose lens care solution (MPS) on interfacial rheology of lipids and mixed lipid-protein films were studied.
METHODS
Lipids were extracted from lotrafilcon A lenses worn continuously for 1 month. Interfacial properties of the lipids without and with lysozyme in the aqueous phase were examined using tensiometry and step-strain relaxation. Lipid-lysozyme multilayers were exposed to either diluted opti-free express (OFX) or opti-free replenish (OFR) for 30 min, and then MPS was displaced from the bulk phase. Surface tension and rheological parameters before and after MPS exposure were measured and compared.
RESULTS
Thick lipid films exerted high surface pressure at the air-aqueous interface, 50 +/- 2 mN/m, with little inter- and intrasubject variability. The rheological storage modulus (E(infinity); 25.3 +/- 2 mN/m) and relaxation time (tau; 87 +/- 25 s) were similar among subjects. Neither lysozyme nor MPS changed the surface tension of the lipid multilayers. Lysozyme adsorbed irreversibly onto multilayers without changing E(infinity), but increased tau 2.5 times. Exposure of mixed multilayers to OFX reduced E(infinity) to less than a half of its original value (13 +/- 4.5 mN/m; p < 0.001), whereas after OFR exposure, small but statistically significant changes in E(infinity) were found (21 +/- 3.0 mN/m; p = 0.0044). MPS-treated mixed films relaxed much slower than an untreated one, tau increased 4.5 times after OFX and 7 times after OFR exposure.
CONCLUSIONS
Thick multilayers of the ex vivo tear lipids have exhibited surface tension 15 +/- 1 mN/m lower than reported in the literature for meibomian lipids. The lipid-lysozyme interaction altered the interfacial rheology of the ex vivo lipids. OFX and OFR changed rheological properties of the mixed films to different extents.
目的
评估厚度可控且可变的离体泪液脂质多层膜的界面特性。研究了溶菌酶和含表面活性剂的多功能隐形眼镜护理液（MPS）对脂质以及脂质 - 蛋白质混合膜界面流变学的影响。
方法
从连续佩戴1个月的lotrafilcon A镜片中提取脂质。使用张力测量法和阶跃应变松弛法检测水相中有无溶菌酶时脂质的界面特性。将脂质 - 溶菌酶多层膜暴露于稀释的optifree express（OFX）或optifree replenish（OFR）中30分钟，然后从本体相中置换出MPS。测量并比较MPS暴露前后的表面张力和流变学参数。
结果
厚脂质膜在气 - 水界面施加高表面压力，为50±2 mN/m，受试者间和受试者内变异性较小。受试者之间的流变储能模量（E(∞)；25.3±2 mN/m）和松弛时间（τ；87±25 s）相似。溶菌酶和MPS均未改变脂质多层膜的表面张力。溶菌酶不可逆地吸附到多层膜上，未改变E(∞)，但使τ增加了2.5倍。混合多层膜暴露于OFX后，E(∞)降至其原始值的一半以下（13±4.5 mN/m；p < 0.001），而暴露于OFR后，E(∞)有小但具有统计学意义的变化（21±3.0 mN/m；p = 0.0044）。经MPS处理的混合膜松弛比未处理的膜慢得多，OFX暴露后τ增加4.5倍，OFR暴露后τ增加7倍。
结论
离体泪液脂质的厚多层膜表现出的表面张力比文献报道的睑板腺脂质低15±1 mN/m。脂质 - 溶菌酶相互作用改变了离体脂质的界面流变学。OFX和OFR在不同程度上改变了混合膜的流变学性质。
Zotero 插件