Boron nitride nanoplate-based improvement of the specificity and sensitivity in loop-mediated isothermal amplification for Vibrio parahaemolyticus detection

Background: Nucleic acid testing based on DNA amplification is gradually entering people's modern life for clinical diagnosis, food safety monitoring and infectious disease prevention. Polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) are the most powerful techniques that have been the gold standard for quantitative nucleic acid analysis. However, the high nonspecific amplification rate caused by the formation of primer dimers, hairpin structures and mismatched hybridization severely restricts their real-world applications. It is highly desirable to explore a way for improving the specificity and sensitivity of PCR and LAMP assays. Results: In this work, we demonstrated that a nanomaterial boron nitride nanoplate (BNNP), due to its unique surface properties, can interact with the main components of the amplification reaction, such as single stranded primers and Bst DNA polymerase, and increase the thermal conductivity of the solution. As a result, the presence of BNNPs dramatically improved the specificity of PCR and LAMP. And BNNPs maintained the specificity even after five rounds of PCR. Moreover, the sensitivity of LAMP was also enhanced by BNNPs, and the detection limit of BNNP-based LAMP was two orders of magnitude lower than that of classical LAMP. Then the BNNP-based LAMP was applied to detect Vibrio parahaemolyticus in contaminated seafood samples with high specificity and a 10-fold increase in sensitivity. Significance: This is the first systematic demonstration of BNNPs as a promising additive to enhance the efficiency and fidelity of PCR and LAMP amplification reactions, thereby greatly expanding the application of nucleic acid detection in a wide range of laboratory and clinical settings.