Development of dual strip biosensors based on hybridization chain reaction and microplate strategies for signal amplification of HBV-DNA detection

Hepatitis B virus (HBV) can cause liver cancer, thus the detection of HBV-DNA is of great significance for liver cancer prevention. Since the concentration of HBV-DNA is often low, it is important to establish a highly sensitive detection method. In this study, microplate amplification and hybridization chain reaction (HCR) were used to improve the sensitive detection of HBV-DNA on dual strip biosensors. For the microplate-based amplification strategy on RS strip, the dual-DNA-AuNP probe could be immobilized on SA-Biotin-Anti-HBV-DNA-1 covered microplate through HBV-DNA. By adding dithiothreitol (DTT), a large amount of HS-RS-DNA on the dual-DNA-AuNP probe was dissociated. The indirect detection of HS-RS-DNA on RS strip could achieve the signal amplification of HBV-DNA. For the HCR-based strategy on HCR strip, HBV-DNA triggered the cascade reaction of H1-AuNP probe and H2-Biotin, a large amount of HCR product (AuNP-H1-H2-Biotin-AuNP-H1…) was produced. Thus, a lot of AuNP was fixed on the test zone of HCR strip to improve the HBV-DNA detection sensitivity. The detection limits by HCR strategy on HCR strip and microplate strategy on RS strip could reach to 5 pM and 0.1 nM, respectively, which were 200 and 10-fold higher than that of unamplified strategy, respectively. The recovery of HBV-DNA ranged from 97.2 to 102 % in the spiked human serum, presented a good accuracy for HBV-DNA detection in actual samples.