title: Distance-based microfluidic quantitative detection methods for point-of-care testing.
abstract: Equipment-free devices with quantitative readout are of great significance to point-of-care testing (POCT), which provides real-time readout to users and is especially important in low-resource settings. Among various equipment-free approaches, distance-based visual quantitative detection methods rely on reading the visual signal length for corresponding target concentrations, thus eliminating the need for sophisticated instruments. The distance-based methods are low-cost, user-friendly and can be integrated into portable analytical devices. Moreover, such methods enable quantitative detection of various targets by the naked eye. In this review, we first introduce the concept and history of distance-based visual quantitative detection methods. Then, we summarize the main methods for translation of molecular signals to distance-based readout and discuss different microfluidic platforms (glass, PDMS, paper and thread) in terms of applications in biomedical diagnostics, food safety monitoring, and environmental analysis. Finally, the potential and future perspectives are discussed.
authors.affiliation: MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Collaborative Innovation Center of Chemistry for Energy Materials, Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. cyyang@xmu.edu.cn zhuzhi@xmu.edu.cn.
authors.forename: Tian
authors.initials: T
authors.lastname: Tian
authors.affiliation: MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Collaborative Innovation Center of Chemistry for Energy Materials, Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. cyyang@xmu.edu.cn zhuzhi@xmu.edu.cn.
authors.forename: Jiuxing
authors.initials: J
authors.lastname: Li
authors.affiliation: MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Collaborative Innovation Center of Chemistry for Energy Materials, Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. cyyang@xmu.edu.cn zhuzhi@xmu.edu.cn.
authors.forename: Yanling
authors.initials: Y
authors.lastname: Song
authors.affiliation: MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Collaborative Innovation Center of Chemistry for Energy Materials, Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. cyyang@xmu.edu.cn zhuzhi@xmu.edu.cn.
authors.forename: Leiji
authors.initials: L
authors.lastname: Zhou
authors.affiliation: MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Collaborative Innovation Center of Chemistry for Energy Materials, Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. cyyang@xmu.edu.cn zhuzhi@xmu.edu.cn.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Collaborative Innovation Center of Chemistry for Energy Materials, Key Laboratory for Chemical Biology of Fujian Province, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China. cyyang@xmu.edu.cn zhuzhi@xmu.edu.cn.
authors.forename: Chaoyong James
authors.initials: CJ
authors.lastname: Yang
mesh_terms: D006801:Humans; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D000067716:Point-of-Care Testing