Description
The SPINeasy DNA Purification Kit is designed for the removal of contaminants that may co-purify with DNA and inhibit downstream enzymatic, PCR applications. Inhibitory compounds such as those found in environmental samples (humic acid, heavy metals, etc.), as well as organic compounds that may co-purify with DNA from other extraction procedures, are efficiently and quickly removed using this kit. The kit offers two choices of binding buffers. Buffer P1 is recommended for purification of samples with slight contamination of humic acids (light brownish color) or other PCR inhibitors. Buffer P1HA contains a novel and proprietary humic acid removal technology, which is recommended for processing samples contaminated with a considerable amount of humic substances (strong brownish color). The kit has been validated with genomic DNA isolated from various problematic soil samples, as well as with DNA samples spiked with humic acid molecules. The data shows that the kit can clean up to 50 µg DNA with a size ranging from 200 bp to high molecular weight, with expected recovery of > 80%. Cleaned-up DNA samples can be readily used in downstream applications, including long fragment PCR, qPCR, and next-generation sequencing (16S and whole genome).
Performance Data
An ideal DNA extraction process shall effectively remove inhibitory substances without compromising the DNA yield. As compared to competitor Z kit, variously contaminated samples purified using the SPINeasy DNA Purification Kit displayed the highest A260/A280 and A260/A230 purity ratios. Moreover, all of the purified samples showed no inhibition in PCR or qPCR, indicating the absence of contaminants and inhibitors.
A. SPINeasy DNA Purification Kit improves A260/A280 and A260/A230 ratios of sample contaminated with chemicals (SDS, chaotropic salts, solvents, humic acid) or both chemicals and proteins.
B. DNA samples spiked with humic acid were purified using SPINeasy DNA Purification Kit or a competitor Z kit. Using end point PCR (left), no amplification was observed in absence of purification as well as after purification with competitor Z kit due to the presence of inhibitory humic acid. Conversely, all the PCR products were successfully obtained upon purification with SPINeasy DNA Purification Kit, indicating an efficient removal of humic acid. In line with this, as compared to SPINeasy DNA Purification Kit, a delayed quantitative amplification was observed with competitor Z(quantitative PCR, right). Endpoint and quantitative PCR were performed in a final volume of 20 μL, using ~120 ng and ~50 ng of DNA, respectively.