Many of the error products commonly formed by Taq polymerase also are removed.
Figure 2B, lane 2 also illustrates the removal of the higher-mobility error products from the product mixture.
We have developed a technique for removing PCR error products, unincorporated primers and dNTPs from a PCR product mixture using immobilized metal affinity chromatography (IMAC).
The PCR mixture passes through the column and is depleted of primers, nucleotides and error products, producing purified double-stranded product.
Here we describe an efficient method of purifying PCR products by specifically removing error products, excess primers, and unincorporated dNTPs from PCR product mixtures using flow-through metal-chelate affinity adsorption.
From these results, it is clear that IMAC can remove primers, error products and dNTPs from PCR product mixtures, suggesting that IMAC (specifically Cu2+-IDA) is a promising approach to the purification of PCR products.
In addition to the primers, in the concentrated eluates a smear of Taq PCR error products can be seen below the 280 bp product (Figure 2B, lane 7); these are effectively removed by IMAC (Figure 2B, lane 2).
Similar results as shown for lambda DNA were obtained for removal of PCR error products from products of PCR amplification of a 1.1 kbp D-alanine-D-alanine ligase A gene from E.coli genomic DNA (data shown in Figure S1).
All potential error products represented together 2.8% of the most abundant sequence.
