Electrophoresis of amplicons is a better method to understand the performance of loop-mediated isothermal amplification assay for screening the presence of Escherichia coli in water

Abstract

LAMP assay is widely used for detecting pathogens. We observed that the conventional and gradient polymerase chain reaction (PCR) could not detect the extracted Escherichia coli DNA; real-time PCR was able to detect up to a certain limit (10−8 bacterial dilution). At the same time, the LAMP assay could detect the bacteria at a much lower concentration (10−14 dilution). The results of the LAMP assay were evaluated using agarose gel electrophoresis and DNA binding dye (PicoGreen), but only gel electrophoresis gave reliable results. Therefore, we propose using electrophoresis-based amplicon detection to overcome the limitations of dye-based detection. We believe that this amplicon detection will go a long way in the screening of potable drinking water.

Keywords

• dna
• dyes
• escherichia coli
• electrophoresis
• lamp assay
• water contamination