Aptamer-based enrichment system and capillary chip for low-abundance water contaminant detection to ensure aquaculture safety and quality

水产养殖是指在淡水或海水中养殖鱼类、贝类和水生植物，是加拿大快速增长的经济产出，产值达7.33亿美元。具有药物作用的污染物正从污水中渗入自然水系，海洋毒素持续存在于地表水中。尽管这些污染物的浓度很低，但它们不断被鱼类和贝类摄入，改变了它们的生长，从而极大地影响了水产养殖的产量。更重要的是，海洋毒素在水产养殖产品中积累并被消费者摄入，造成严重的食物中毒、器官损伤和癌症。因此，非常需要高度敏感、快速和用户友好的现场可部署监测工具来检测微量污染物，进行水质调查，识别和评估点和非点污染源，建立浓度限制并根据分析对收获区域进行分类。微流控生物传感器在自动化和小型化检测方面变得越来越强大，但低丰度环境分析物的浓度需要大容量，这对于基于芯片的设备来说是不切实际的。收集足够的分析物的浓缩技术，如固相萃取和蒸发，耗时，劳动密集，容易污染，往往效率低下，不适合现场使用。我们建议开发一种便携式检测系统，该系统结合了基于适配体的分析物富集机制和用于不干涉处理的微流控芯片，并集成了基于石墨烯的敏感传感器。该项目将建立一种新的分析物富集和检测技术，该技术具有超高灵敏度，达到目前现场部署方法无法达到的检测极限。

Aquaculture is the farming of fish, shellfish and aquatic plants in fresh or seawater and has been a rapidly growing economy output of $733 millions in Canada. Contaminants with pharmaceutical effects are seeping from the sewage into natural water systems, and marine toxins persist in surface water. These contaminants, despite their very low concentrations, are constantly ingested by fish and shellfish, altering their growth and thereby greatly affecting the yield of aquaculture. More importantly, marine toxins accumulate in aquaculture products and are ingested by consumers, causing serious food poisoning, organ damages and cancers. There is therefore a great need for highly sensitive, rapid and user-friendly field deployable monitoring tools for detection of trace amount of contaminants, to conduct water quality surveys, identify and assess source of point and non-point pollution, establish concentration limits and classify harvest areas based on the analysis.Microfluidic biosensors are becoming more powerful in automating and miniaturizing detection, but the concentration of low abundance environmental analytes requires large volumes that are not practical for chip-based devices. Concentration techniques to collect sufficient analytes, such as solid phase extraction and evaporation are time-consuming, labor-intensive, contamination-prone, often inefficient and not compatible with field use. We propose to develop a portable detection system combining an aptamer-based analyte enrichment mechanism, and a microfluidic chip for hands-off processing, integrated with a sensitive graphene-based sensor. The project will establish a novel analyte enrichment and detection technology that is capable of ultra-high sensitivity, reaching detection limit not achievable by current field deployable methods.