Related Experiment Video
Updated: May 11, 2026

Tools to Study the Role of Architectural Protein HMGB1 in the Processing of Helix Distorting, Site-specific DNA Interstrand Crosslinks
Published on: November 10, 2016
Specific recognition of supercoiled plasmid DNA by affinity chromatography using the intercalator DAPP as ligand
C Caramelo-Nunes1, P Almeida, J C Marcos
1CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã, Portugal.
Abstract:
Small molecules that bind DNA with high specificity present a promising opportunity for application as chromatographic ligands for plasmid DNA (pDNA) purification. This research used the intercalator 3,8-diamino-6-phenylphenanthridine (DAPP) as an immobilized ligand for the specific separation of supercoiled (sc) pDNA by affinity chromatography. The results showed that the protonated DAPP-Sepharose support has a great affinity for sc pDNA isoform, separating it from the less active open circular and linear isoforms. All pDNA isoforms were retained in the column using 10mM acetate buffer pH 5. Selective elution of oc and linear isoforms was achieved with 0.22M of sodium chloride in the same buffer. Finally, increasing the concentration to 0.55M led to the elution of the sc isoform. The binding of pDNA to DAPP-Sepharose varies in function of pH, and the stability of the protonated DAPP-DNA complex decreases with increasing salt concentration.
More Related Videos
12:24DNA-affinity-purified Chip (DAP-chip) Method to Determine Gene Targets for Bacterial Two component Regulatory Systems
Published on: July 21, 2014
07:55Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
Related Concept Videos
Southern Blot
Denatured DNA fragments must be transferred onto a carrier membrane from the gel to make it accessible to a probe - a small ssDNA fragment complementary to the target DNA...
Single-Strand DNA Binding Proteins
DNA Isolation
Labeling DNA Probes
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...