Plasmonic LAMP: Improving the Detection Specificity and Sensitivity for SARS‐CoV‐2 by Plasmonic Sensing of Isothermally Amplified Nucleic Acids
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.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 07, 2022
- Source ID
- 10.1002/smll.202107832
Entities
People
- Chance Nowak
- Haihang Ye
- Leonidas Bleris
- Tingting Zhang
- Yaning Liu
- Yi Li
- Zhenpeng Qin
Organizations
- National Institutes of Health
- National Science Foundation
- United States Department of Defense
- University of Texas at Austin
- University of Texas at Dallas