Lab-on-card based sensor for DNA detection using Loop-mediated isothermal amplification

Abstract

Molecular diagnostics are very attractive tools for pathogen detection. But, the conventional molecular diagnostics are unsuitable for poor point of care (POC). So, miniaturizing lab devices towards a Lab-on-card (LOC) is useful in POC. We aimed to translate macro-lab techniques to a single LOC sensor for cell lysis & DNA extraction, amplification & detection using Loop-Mediated isothermal amplification (LAMP). LAMP is sensitive, cheap, rapid and very appealing for POC. So, we hypothesized “LAMP can be incorporated for the development of a LOC sensor for DNA extraction, amplification and detection”.The next goals were tested on card: cell extraction, cell lysis & DNA extraction, mixing samples &reagents, and optical DNA detection. A card was designed to test each step separately. Artificial sputum is prepared & liquified by hot water. Cells were extracted by filter paper. Thermal cell lysis was tested by microheater & DNA extraction was estimated by Nanodrop. A micromixer is tested to mix the reagents. The detection of the DNA amplicons was performed by a photosensor on card. Here we provided cards that can, extract cells in sputum, rupture cells and extract DNA thermally, mix sample and reagents, detect the DNA by a photosensor. Each step was tested on card separately.To conclude, each step of the DNA sensor was performed by LOC. Hence, the development of a single DNA card sensor is very promising which is of great value in POC & remote settings