基于荧光法纸基器件在体外疾病检测中的应用进展

In poor areas of the developing countries, many diseases are delayed for treatment due to the lack of medical equipment and professional care. There are as many as 500 million malaria patients failed to be diagnosed in the early phase of infection every year, hence leading to more people being injected. Therefore, the devices that are simple, inexpensive, convenient and portable, without the need for auxiliary equipment (such as electricity, pumps, optical devices, etc.) are of urgent need for these areas to detect common diseases. Commonly used detection methods for paper-based devices include colorimetry, electrochemistry, chemiluminescence, electrochemiluminescence. The paper-based devices can be adopted in the early detection of diseases, food quality control and environmental monitoring. Thus, the rapid, high selectivity, high sensitivity, and relatively low cost and pollution-free advantages of the paper-based devices make them favored by in vitro detection and related application testing. Despite of the advantages of the paper-based devices, some challenges still remain to be solved prior to wide practical applications. For example, how to improve the diversity, stability, repeatability of the paper-based device detection, and the portability of the detection devices. Co-lorimetry is the most intuitive and commonly used detection methods, which based on the chromogenic reaction (resulting from the aggregation and/or separation of nanocrystals induced by chemical/biochemical reactions between target analytes and colorimetric probes) performs semi-quantitative analysis by visual observation, yet generally produces errors due to the visual senses of different examiners. In addition, the limitation of this method lies in its vulnerability to light, and poorer sensitivity and selectivity than that of the electrochemical methods. The fluorescence method exhibits good selectivity and low detection limit, but still have great development space in the portability of the detection devices. The electrochemistry, chemiluminescence, electrochemiluminescence have certain superiorities in detecting sensitivity and selectivity, yet the electrode pollution and high background signal-to-dry ratio of restrict their extensive application. Therefore, in recent years, researchers not only concentra-ted on the investigations of material properties and device performance, but also achieved leap-forward results in the high-throughput detection techniques. This paper summarizes the development and application of the fluorescent detection on paper-based devices, introduces the fluorescent mate-rials including organic dyes, quantum dots, metal nanoclusters, upconverting nanoparticles, carbon dots, etc., and illustrates their application in in vitro detection, for example, nucleic acid detection, protein detection, cells detection and so on, points out their defects in the application as well. Therefore, it is imperative to design new types of optical materials with stable, high yield, anti-bleaching, low toxic, good biocompatible and large stoker displacement. Finally, this paper looks forward to the application prospects of fluorescent paper-based devices as an early diagnosis of disease prevention.