水产食品化学危害物免疫检测中基质效应的产生机制及消除途径

The immunoassay is now considered one of the most prospective techniques for routine fast screening of harmful chemicals large numbers of food samples. However, some drawbacks of such immunoassays were also exhibited which can greatly limit their further developments and applications: some food components could greatly interfere with the immunoassays (which is so called "matrix effect"), and then result in relatively poorer precision, repeatability and reproducibility, as well as complex pretreatments of food samples, which makes them unable to use in many cases, for example field analysis in small factories and farms. Clarification of the mechanism involved in the matrix interference, as well as the development of reasonable techniques to eliminate such an interference, is now became a task in the field of food immunoassays. .Here in this project, the exact source of the matrix effect in the immunoassay of typical harmful chemicals (such as drug residues) in aquatic food will be carefully studies. The main food components to cause the matrix interference will be localized, and their basic properties (such as solubility) will be examined. Making use of surface plasma resonance and other techniques, the interaction between the food matrix and other factors in the immunoassays will be investigated, and the detailed mechanism on the origin, development and relative factors to affect the matrix effect will be further clarified. Based on above results, strategies to eliminate or diminish the matrix interference would be discussed and preliminarily validated. All these results will make a solid foundation for the development of more simple, fast, and effective immunoassay of aquatic food samples in the future.

免疫检测技术是最具发展前景的化学危害快速检测手段之一，但食品基质组分对于免疫反应的严重干扰（基质效应），会显著降低检测灵敏度和可靠性，并导致前处理过程较为复杂、繁琐，整个检测体系的快速简便性不能充分体现，难以满足企业及政府部门日常筛选检测的要求。明确基质效应的产生机制、建立针对性的消除控制方法，是目前食品免疫检测领域亟待解决的一个瓶颈问题。.本课题拟针对药残、非法投入品等化学危害的免疫检测过程，研究确定鱼虾等水产食品基质中主要的干扰组分，测定其溶解度等基本性质；利用表面等离子共振等技术手段，研究以上干扰组分与免疫检测相关因素之间的相互作用特征，进一步阐明基质效应的产生途径、作用过程及影响因素；在此基础上研究探讨能针对性消除基质干扰、最大程度简化前处理过程、显著提高整体检测效率的技术方法，并进行初步验证；为下步研究开发更加快速、简便、可靠的免疫检测技术和产品建立理论依据和方法学基础。

免疫分析检测过程中一个最为基本的问题就是样品或样品提取物中极其复杂多变的蛋白质、碳水化合物、脂质、小分子所产生的影响。因此本项目旨在分析评价水产品药物残留等化学危害物免疫分析检测过程中基质影响程度，分析主要的的基质干扰来源，并探究这种干扰作用的机理，建立简便有效快速的基质干扰消除方法。通过系统分析水产品中可能产生基质干扰的组分，证明部分水溶性蛋白质组分是鱼类免疫分析检测过程中的主要干扰组分，多糖可能是海参胶体金免疫分析检测过程中的重要干扰组分，部分金属离子也能对水产品免疫分析检测过程产生显著影响。随后，实现了对其中两种主要基质干扰蛋白(36 kD和42 kD蛋白)的分离纯化和性质的研究,并通过免疫印迹方法确认验证，同时以鱼肉蛋白为代表探索了水产品蛋白组分干扰免疫分析检测过程的机理，结果表明鱼肉中的某些蛋白质与免疫球蛋白IgG存在非特异性作用，这种作用可能是蛋白质干扰免疫分析检测的重要来源，进一步的研究中，金属离子也有可能与某些抗体结合而干扰免疫分析检测。研究了热、酸处理等不同的手段对于典型水产品的基质干扰消除性能，开发出简单快速的样品前处理方法，可以减少和避免了前处理过程的盲目性，为进一步提升免疫分析检测的简便快速性提供了理论依据和方法学基础。