Abstract
The ability to detect pathogens specifically and sensitively is critical to combat infectious diseases outbreaks and pandemics. Colorimetric assays involving loop-mediated isothermal amplification (LAMP) provide simple readouts yet suffer from the intrinsic non-template amplification. Herein, a highly specific and sensitive assay relying on plasmonic sensing of LAMP amplicons via DNA hybridization, termed as plasmonic LAMP, is developed for the severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) RNA detection. This work has two important advances. First, gold and silver (Au-Ag) alloy nanoshells are developed as plasmonic sensors that have 4-times stronger extinction in the visible wavelengths and give a 20-times lower detection limit for oligonucleotides over Au counterparts. Second, the integrated method allows cutting the complex LAMP amplicons into short repeats that are amendable for hybridization with oligonucleotide-functionalized Au-Ag nanoshells. In the SARS-CoV-2 RNA detection, plasmonic LAMP takes ≈75 min assay time, achieves a detection limit of 10 copies per reaction, and eliminates the contamination from non-template amplification. It also shows better detection specificity and sensitivity over commercially available LAMP kits due to the additional sequence identification. This work opens a new route for LAMP amplicon detection and provides a method for virus testing at its early representation.
Keywords: SARS-CoV-2; hollow nanostructures; homogeneous assays; loop-mediated isothermal amplification; plasmonics.
【저자키워드】 SARS-CoV-2, Loop-mediated isothermal amplification, hollow nanostructures, homogeneous assays, plasmonics., 【초록키워드】 coronavirus, Infectious diseases, Infectious disease, virus, RNA, Severe acute respiratory syndrome, amplification, DNA, sensitivity, specificity, Contamination, pathogen, Loop-mediated isothermal amplification, outbreak, LAMP, Pandemics, gold, Pathogens, isothermal amplification, Severe acute respiratory syndrome-related coronavirus, silver, Critical, Detection limit, SARS-CoV-2 RNA detection, Amplicon, isothermal, acute respiratory syndrome, reaction, complex, sequence, oligonucleotides, hybridization, second, oligonucleotide, wavelength, intrinsic, detect, provide, homogeneous, the SARS-CoV-2, 【제목키워드】 detection, acid, Improving,