Polymerase chain reaction combined with fluorescent lateral flow immunoassay based on magnetic purification for rapid detection of canine parvovirus 2

Zhuang, Linlin; Ji, Yongxin; Tian, Peilong; Wang, Kaixuan; Kou, Chengkun; Gu, Ning; Zhang, Yu

To avoid gel electrophoresis and provide a portable, cost-effective platform to record results, PCR combined with lateral flow immunoassays (LFIAs), such as gold nanoparticle (AuNP)-based LFIAs, have been conducted [16] [17] [18] . PCR-LFIAs are convenient, quick and easy-operating. However, primer dimers and hairpins are known features in molecular diagnostic assays [19, 20] . Due to the primer as a modified carrier, the dimer formed by the upstream and downstream primers also has the characteristic of PCR amplification products, which can also be recognized as a positive by the LFIA. To overcome the obstacles of false positive result, researchers have been exploring some effective ways to address primer dimers to increase the accuracy and specificity [21, 22] . The probe method can reduce the effect of primer dimers, but it is still based on the principle of nucleic acid hybridization and difficult to solve the problem of primer (probe) dimers fundamentally. Furthermore, it not only adds the complexity of design and operation, but also increases inspection cost and time. On the other hand, the nucleic acid denaturant-based methods have great influence on DNA amplification products and the detection limit is affected. There is an urgent need in improved method for PCR products processing to higher accuracy.