利用复合多肽纳米水凝胶对猪流行性腹泻病毒进行高灵敏检测及靶向诊疗

冠状病毒不仅给养殖业造成重大损失，而且对人类健康造成严重危害。目前大多数冠状病毒致病机制仍不清楚，且缺乏高灵敏检测手段及有效治疗药物。本课题拟在合成包埋碳点及硫化银量子点的多肽纳米水凝胶基础上，以猪流行性腹泻病毒(PEDV)为模式冠状病毒，通过配体指数富集系统进化技术，筛选可特异性识别PEDV及PEDV感染细胞的核酸适体，并将核酸适体修饰到纳米水凝胶表面，获得多功能复合多肽纳米水凝胶。采用荧光分析及荧光成像等技术，实现对PEDV变异毒株及PEDV感染细胞的精准识别及高灵敏检测。利用核酸适体对病毒特异识别及病毒nsp5蛋白对复合多肽纳米水凝胶特异响应特点，实现对PEDV增殖的靶向抑制。在此基础上，以微型猪为模型，揭示病毒在猪肠道内的分布规律，评价复合多肽纳米水凝胶对PEDV的靶向诊疗效果。本项目不仅为冠状病毒检测提供新的技术、为PEDV的防控提供新的思路，对其他病毒的研究也可提供一定的借鉴。

Coronavirus not only causes great losses to the breeding industry, but also causes serious harm to human health. At present, the pathogenesis of most coronaviruses is still unclear, and highly sensitive detection methods and effective treatment drugs is also lack. In this project, Polypeptide nano hydrogel embedded with carbon dots and silver sulfide quantum dots are prepared, and, the aptamers of porcine epidemic diarrhea virus (PEDV)and PEDV infected cells are screened by ligand index enrichment system evolution technology by using PEDV as a model of coronavirus. The selected aptamers were futher modified to the surface of nanoscale hydrogel to obtain multifunctional composite polypeptides nano hydrogels. The accurate identification and highly sensitive detection of PEDV mutant and PEDV infected cells were obtained by using fluorescence analysis and fluorescence imaging technology. Targeted inhibition of PEDV proliferation was achieved due to aptamer specific recognition of PEDV and viral nsp5 protein specific response characteristics on composite polypeptides nano hydrogels. On this basis, the distribution pattern of virus in pig intestine was revealed by using miniature pig as a model, and the effect of composite polypeptides nano hydrogels on the targeted treatment of PEDV was evaluated. This project not only provides new technology for coronavirus detection, but also provides new ideas for prevention and control of PEDV, which provides some references for other virus research.