生物传感器已被用于一系列引人注目的应用，包括传染病、环境监测、癌症诊断、食品安全等。特别是，全球COVID-19大流行暴露了对快速检测的需求，因此最近引起人们极大兴趣的生物传感器类型是用于快速诊断的免疫测定。纸基侧流和试纸免疫测定的性能受到纳米粒子 (NP)、NP-抗体缀合物和纸基质的物理性质的影响。许多材料创新通过提高灵敏度或实现独特的读数来增强诊断。然而，生物样品和生物分子与纳米粒子或纸基材之间的界面可能会产生负面影响，例如非特异性吸附和蛋白质变性。在本视角中，我们讨论了免疫测定组件，并重点介绍了可以提高灵敏度的化学和材料创新。我们还探索了一系列可能给免疫分析带来挑战的生物界面问题。

Biosensors have been used for a remarkable array of applications, including infectious diseases, environmental monitoring, cancer diagnosis, food safety, and numerous others. In particular, the global COVID-19 pandemic has exposed a need for rapid tests, so the type of biosensor that has gained considerable interest recently are immunoassays, which are used for rapid diagnostics. The performance of paper-based lateral flow and dipstick immunoassays is influenced by the physical properties of the nanoparticles (NPs), NP-antibody conjugates, and paper substrate. Many materials innovations have enhanced diagnostics by increasing sensitivity or enabling unique readouts. However, negative side effects can arise at the interface between the biological sample and biomolecules and the NP or paper substrate, such as non-specific adsorption and protein denaturation. In this Perspective, we discuss the immunoassay components and highlight chemistry and materials innovations that can improve sensitivity. We also explore the range of bio-interface issues that can present challenges for immunoassays.