金属稳定同位素标记生物分析进展

细胞和组织的很多特定功能都由其在不同的生理条件下的生物分子含量决定,极少数分子的改变就有可能影响细胞生物功能并触发疾病生理过程,因此高灵敏的生物分子检测技术在疾病机理研究和疾病早期诊断方面具有重要作用。金属稳定同位素和放射同位素化学性质相近,借鉴放射同位素标记的成功经验,通过金属稳定同位素标记多组分生物分子,可以用原子质谱高灵敏地检测多组分生物分子。作为灵敏准确的金属元素检测工具,电感耦合等离子体质谱检出限低、基体效应低、线性范围广、同位素谱线分辨率高,因此适用于金属元素标记生物分子检测。金属稳定同位素标记已经被广泛应用到蛋白质、核酸、酶活性、生物小分子、甚至单个细胞的检测中,取得了一些可喜的进展,并展现了广阔未来应用前景。金属稳定同位素标记生物分析方法有三个特性：高灵敏度-大多数金属的稳定同位素有较高的标记灵敏度,并且可以通过纳米材料标记等方法实现信号放大;多组分同时分析-质谱仪同位素谱线高分辨率提供了多组分分析能力;高准确度-同位素稀释法提供了可溯源到SI国际单位制的高准确度检测结果。为了更好的推动相关研究,简要介绍金属稳定同位素标记生物分析的进展,主要内容包括以下几个部分：金属稳定同位素检测工具-无机质谱、金属稳定同位素标记高灵敏度分析、金属稳定同位素标记多组分同时分析、金属稳定同位素标记高准确度分析、金属稳定同位素标记单细胞分析的进展。     

Bioactive Luminescent Silver Clusters Confined in Zeolites Enable Quick and Wash-Free Biosensing

The simultaneous capture and detection of biomolecules is crucial for revolutionizing bioanalytical platforms in terms of portability, response time and cost-efficiency. Herein, we demonstrate how the sensitivity to external stimuli and changes in the local electronic environment of silver clusters lead to an advantageous biosensing platform based on the fluorometric response of bioactive luminescent silver clusters (BioLuSiC) confined in faujasite X zeolites functionalized with antibodies. The photoluminescence response of BioLuSiC was enhanced upon immunocomplex formation, empowering a wash-free and quick biodetection system offering optimal results from 5 min. Proteins and pathogens (immunoglobulin G and Escherichia coli) were targeted to demonstrate the biosensing performance of BioLuSiC, and a human serum titration assay was also established. BioLuSiC will pave the way for innovative bioanalytical platforms, including real-time monitoring systems, point-of-care devices and bioimaging techniques.