Construction And Application Of Biosensors For Point-of-care Testing Based On Paper-based Chips

Severe fever with thrombocytopenia syndrome bunyavirus(SFTSV)is a new type of bunyavirus with high susceptibility and mortality in China.More and more cases of infection have been greeted with an avalanche of publicity in society.However,the research on the virus is still in its infancy,and no effective methods and vaccines have been found for its treatment and prevention.In addition,the understanding of the pathogenesis is limited.Nowadays,nucleic acid and immunology detection are commonly used in the detection of SFTSV in scientific research,but these methods are not only expensive but also tedious.In order to effectively screen and detect viruses and control the spread of diseases,the research of a fast and accurate detection method has greatly important value and significance.On the other hand,microfluidic paper-based analytical devices(?PADs)have the characteristics of less sample consumption,fast detection speed,simple operation,multi-functional integration,portability and miniaturization,so they have broad application prospects,especially in remote areas with limited resources,daily point-of-care testing(POCT)and pre-disease screening and diagnosis.Therefore,an effective method for fast detection of SFTSV by using ?PADs was constructed for the first time,which provides more possibilities for its qualitative and quantitative analysis.The concrete research contents are generalized as below:1.Construction of biosensors for detection of new bunyavirus based on Au-PWE and Quantum Dots electrochemiluminescenceIn this chapter,Au-PWE was firstly used to detect SFTSV sensitively.We used a Wax-jet printer to design ?PADs in batches,and constructed sandwich immunosensor based on quantum dots electrochemiluminescence to detect SFTSV quantitatively.During detection process,the electrochemiluminescence intensity of quantum dots increased with the increase of SFTSV antigen concentration.The detection sensitivity could reach 0.1 pg/mL(S/N=3),and the linear range was from 0.0001 to 50 ng/mL.The results showed that SFTSV biosensor with high sensitivity,outstanding selectivity,excellent repeatability and stability could be constructed based on ?PADs and quantum dots electrochemiluminescence.This chapter is of great value to the early diagnosis and monitoring of SFTSV,and even to the development of portable and low-cost POCT analysis equipments.2.Rapid detection of severe fever with thrombocytopenia syndrome virus via colloidal gold immunochromatography assayIn this chapter,by combining the characteristics of paper-based LFITSs and the optical properties of Au NPs,an immunoassay method for rapid detection of SFTSV was presented for the first time.Paper-based LFITSs has simple structure and high cost-effectiveness.The whole SFTSV detection process could be completed within 10 minutes,and satisfactory results were obtained.Under the optimum conditions,the detection limit of paper-based LFITSs was 1 ng/mL only depending on the visual detection line,and the whole testing process only required 50 ?L of analytical solution.The developed paper-based LFITSs in this chapter are simple,portable,fast,low-cost,stable and specific,which opens up new possibilities for the wide application of POCT analysis equipments in daily life.