近年來，利用液晶分子作為訊號輸出來源的液晶型免疫分析系統已經發展成為新型的檢測平台，我們使用不同的表面修飾策略以研究對於液晶型免疫分析系統靈敏度的影響。由於頻傳的食安事件，促使我們開發食品中非法添加的危害物的感測器，以三聚氰胺為檢測物，設計了三種免疫分析方法來進行檢測，並利用不同的表面修飾方法來將抗體或抗原修飾於表面上。將氧化三聚氰胺一級抗體以共價鍵方式修飾於表面的策略，在直接型免疫分析方法中雖然無法測得三聚氰胺的存在，但能於間接型免疫分析方法中輔以卵白素結合二級抗體得到2.5 ng/mL檢測極限值。競爭型免疫分析方法使用生物素共軛三聚氰胺抗體結合於卵白素修飾表面的策略，能檢測含有50 ng/mL三聚氰胺的溶液。 Recently, the liquid crystal (LC)-based immunoassay which applies liquid crystal molecules as a signal output has been a new detecting platform for immunoassay. In this study, we tried to study the sensitivity impact to LC-based immunoassay by using different surface modification strategy. Due to frequent food safety issues, we decided to develop a sensor for detecting the illegal additives in food. We designed three types of immunoassay to detect melamine, an illegal adulteration in infant formula and pet food, and tried different surface modification strategy to modify antibody or antigen on surface. In direct immunoassay by using the strategy of modified oxidized 1st anti-melamine on surface with covalent bond, it can’t detect the presence of melamine. Within streptavidin combine to 2nd anti-melamine in indirect assay, we can get a detection limit of 2.5 ng/mL melamine. Furthermore, we used the strategy of decorating biotin conjugated anti-melamine on streptavidin modified surface and it could detect the solution containing 50 ng/mL of melamine.
