The presence of a band at 407bp on gel electrophoresis confirmed the amplified product.

The integrity of the isolated DNA was assessed by amplifying the 16S rRNA gene using Com1 and Com2 universal primers. Six gram-negative waterborne pathogens were used to demonstrate the efficacy of the microchip based DNA extraction process. The complete isolation of the DNA using the microchip took ~ 15min as against>2h with a TRIzol method.

DNA extracted using the microchip was pure with absorbance (260/280) ratio of 1.77☐.04, as compared to 1.79☐.03 obtained by TRIzol method. The magnetic nanoparticle-DNA complex was then isolated from the in-flow matrix using permanent magnet, Further, removal of the cell debris, proteins, and carbohydrates was done using wash buffer. The released DNA was captured by the nanoparticles owing to its positive charge (chitosan coating). The microchip facilitated in-flow coating of chitosan on the magnetic nanoparticles, which under external mechanical vibration caused cell lysis and released DNA in the supernatant. To obtain high quality DNA rapidly, we have fabricated a microchip in poly(dimethyl siloxane) (PDMS) by soft lithography process. Molecular tools require DNA as the starting material for diagnosis, and hence, a prerequisite is the quality and integrity of DNA. For accurate diagnosis, molecular tools have gained considerable attention in the recent past. Globally, waterborne organisms are the primary causative agents for the transmission of various forms of diarrheal diseases.

Cell lysis buffer for dna extraction