利用液晶取向变化的光学免疫检测方法  

Optical Detection of Immunoreaction Based on the Orientation Transition of Liquid Crystal

作　　者：熊兴良[1] 蔡绍皙[2] 李苑[2] 

机构地区：[1]重庆医科大学生物医学工程研究室,重庆400016 [2]重庆大学生物力学与组织工程教育部重点实验室,重庆400044

出　　处：《高等学校化学学报》2009年第5期891-895,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:30500125);重庆市自然科学基金(批准号:2008BB5395)资助

摘　　要：利用共价固定方法将抗血清白蛋白固定到硅烷化玻璃基底上,并通过摩擦其表面形成5CB液晶整齐均一取向排列的基底.考察了不同浓度的人血清白蛋白与基底作用后液晶在基底上形成的偏光光学图像的差异,并利用自行提出的"图像加权平均灰度值"定量分析了图像灰度与人血清白蛋白浓度的关系.对比研究了基底上的特异性吸附与非特异性吸附引起的液晶偏光光学图像的差异以及调制偏振光能力,结果表明,该基底具有很高的特异性.该方法可望发展成为一种灵敏、非标记的光学免疫检测方法.The uniform orientation of liquid crystal molecule can be changed easily when exposure to different biological environment and thus lead to the changes of optical images obtained from crossed polarized light with liquid crystal sandwiched between polarizer and analyzer. Based on this principle, we report the uniform planar orientation of thermotropie liquid crystals, 4-biphenyl-4′-pentyl-carbonitrile（5CB） , on the films of antihuman serum albumin （anti-HSA） covalently immobilized on the surface of glass microscope slides using （3-aminopropyl） triethoxysilane （3-APTES） and glutaraldehyde （GA） and mechanically rubbed using a rubbing machine. Following immersion of these rubbed films of anti-HSA into aqueous solutions containing different concentrations of HSA, we observed the differences of images and quantificationally analyzed the relationship between gray scale of images and the concentration of HSA using the concept of weighted average of gray-scale value of image. Following immersion of these rubbed films of anti-HSA into solutions containing HSA, BSA, fibrinogen, lysozyme, we compared specific adsorption with nonspeeific adsorption on these rubbed films of anti-HSA by observed the differences of images and modulation of polarized light. The result suggests that these types of substrates （ rubbed films of proteins） possess high specificity. The provided methods have the potential to be useful in a variety of sensitive, label-free biomolecular detection where specific binding of a target species to its antibody （ or antigen） can be imaged through analyze of the optical image of liquid crystal cell placed onto the surface.

关 键 词：液晶 取向转变 光学检测 人血清白蛋白 

分 类 号：O657.39[理学—分析化学]