School of Chemistry, Australian Centre for NanoMedicine, ARC Centre of Excellence in Convergent Bio-Nano Science and Technology , The University of New South Wales , Sydney , New South Wales 2052 , Australia.
J Am Chem Soc. 2019 Jan 23;141(3):1162-1170. doi: 10.1021/jacs.8b09397. Epub 2018 Dec 4.
This Perspective focuses on the latest strategies and challenges for the development of bioanalytical sensors with sub-picomolar detection limits. Achieving sub-picomolar detection limits has three major challenges: (1) assay sensitivity, (2) response time, and (3) selectivity (including limiting background signals). Each of these challenges is discussed, along with how nanomaterials provide the solutions. One strategy to gain greater sensitivity involves confining the sensing volume to the nanoscale, as used in nanopore- or nanoparticle-based sensors, because nanoparticles are ubiquitous in amplification. Methods to improve response time typically focus on obtaining an intimate mixture between the sensor and the sample either by extending the length scale of nanoscale sensors using nanostructuring or by dispersing magnetic nanoparticles through the sample to capture the analyte. Loading nanoparticles with many biorecognition species is one solution to help address the challenge of selectivity. Many examples in this Perspective explore the detection of prostate-specific antigen which enables a comparison between strategies. Finally, exciting future opportunities in developing single-molecule sensors and the requirements to go even lower in concentration are explored.
本观点聚焦于开发具有皮摩尔级检测限的生物分析传感器的最新策略和挑战。实现皮摩尔级检测限有三个主要挑战：（1）检测灵敏度，（2）响应时间，和（3）选择性（包括限制背景信号）。本文讨论了这些挑战中的每一个，以及纳米材料如何提供解决方案。一种提高灵敏度的策略是将传感体积限制在纳米范围内，如基于纳米孔或纳米颗粒的传感器中，因为纳米颗粒在放大中无处不在。提高响应时间的方法通常侧重于通过在纳米尺度上扩展传感器的长度尺度，或者通过将磁性纳米颗粒分散在样品中以捕获分析物，从而在传感器和样品之间获得更紧密的混合物。通过将许多生物识别物质加载到纳米颗粒上，是解决选择性挑战的一种解决方案。本观点中的许多例子都探索了前列腺特异性抗原的检测，这使得可以在策略之间进行比较。最后，探索了开发单分子传感器的令人兴奋的未来机会，以及甚至更低浓度的要求。
