与日俱增的分析化学测量需求，要求分析方法不仅具有高的灵敏度与选择性，常常还需要能够在一个样品中同时检测多目标物。基于单个信号源的定量计数策略的分析方法，具有高的方法灵敏度，正在逐渐成为分析化学方法中新的主要分析策略之一。金属纳米材料和荧光纳微米材料具有超强的发光亮度，使得单颗粒水平的光学显微成像分析成为生命分析化学领域中重要的发展方向之一。本项目将计数分析这一数字化的信号读出方式与使用普通光学显微镜的单颗粒水平的光学成像分析结合，围绕基于光学显微成像的纳米单颗粒计数方法所涉及的基本科学问题开展研究，通过单颗粒纳米信号报告基团分析性能研究，不同发光纳米颗粒可编码参数以及编码新策略的研究，发展免放大的高灵敏纳米单颗粒显微成像计数分析方法，特别是多目标物的同时检测方法，并尝试实际样品检测中的应用。

The challenges that analytical chemists facing require that the analytical methods are highly sensitive and selective, and often have to be able to detect multiplex analyte of interest in a single test volume. The digital signal from single signal reporter enumeration, which is related to the quantity of analyte, provides better and unbiased measurements of the target quantity, and is emerging as one of the hot analytical strategies. The excellent light-emitting properties of metal nanomaterials and fluorescent microspheres enable the single-particle level optical microscopic imaging analysis with a common-grade optical microscope. Thus, the single-particle based microscopic imaging analysis has become as a promising research field of analytical chemistry. The combination of digital signal output with the single-particle optical imaging is expected to a new efficient approach to achieve highly sensitive and multiplexed assays with modest instrumental and reagent costs and without the need of signal enhancement or target-amplification. This project will focus on development of the optical microscopic imaging based single nano/microparticle enumeration platform for sensitive single and multiple target detection. We will evaluate the basic methodology concerning the particle enumeration based measurements. Studies will focus on evaluating the properties of nanoparticles that will possibly affect the sensitivity of the methods, the new coding strategy on multiplexed detection. We hope the study of this project will expand the breadth of analytical strategies, and will provide an easy and cost-effective approach for sensitive detection of single and multiplex analyte of interest.