Regenerated PCR purification kit columns have a comparable capacity for DNA purification as fresh columns. (A) A scheme showing the workflow and duration for the published regeneration methods and for the 1 M phosphoric acid method. PM: published method. (B) Comparison of DNA elimination using 1 M phosphoric acid and the published methods. The used columns were cleaned with the protocol as shown in A. Thirty microlitres of eluate was obtained from the regenerated columns, 1 μL of which was used for qPCR. The data were processed as shown in Fig. 1C. (C) Comparison of DNA purification efficacy between the regenerated and fresh columns. A 50 μL Tbox 5 PCR reaction was purified with the regenerated or fresh columns, and the DNA concentrations were measured with a Nanophotometer (Thermo Scientific) and then subjected to a statistical analysis. The DNA quality was verified by agarose gel electrophoresis and imaged using a Bio-Rad ChemiDoc XRS + System. Data acquisition and settings are described as in the materials and methods section. The full-length image is presented in Supplementary Fig. S2. The DNA concentration for each sample is shown beneath the gel picture. (D) The regenerated columns showed a similar capacity for purifying different sizes of DNA as the fresh columns. DNA from a 50 μL PCR reaction was purified and quantified as in C. Luc shRNA, Luciferase shRNA cDNA, 70 bp; Hand2, 654 bp, Tbox 5, 1557 bp; pLV-FLNB, 17360 bp. (E) Comparison of DNA purification efficacy between the regenerated and fresh columns from different PCR purification kits. DNA from a 50 μL LIF PCR reaction was purified using regenerated or fresh columns, and the data were processed and presented as in C. Each column in B and D represents the mean ± SD of three independent experiments. *p < 0.05; **p < 0.01 and ***p < 0.001, where p was obtained by a one way ANOVA.