Related Experiment Video
Updated: Aug 5, 2026

Porphyrin-Modified Beads for Use as Compensation Controls in Flow Cytometry
Published on: March 24, 2023
Stronger Affinity of Water-Soluble Cationic Porphyrins to Cancer DNA under Acidic Conditions as a Basis for
Nelli H Karapetyan1, Artem V Badasyan2, Gayane V Ananyan1
1Department of Physics, Yerevan State University, Al. Manoogian 1, 0025 Yerevan, Armenia.
Abstract:
The affinities of porphyrins to healthy and cancer DNA under physiological and acidic conditions were studied. Titration of meso-tetra-(4-N-hydroxyethylpyridyl)-porphyrin and its Ag-substituted derivative solutions with DNAs, isolated from healthy and tumor tissues, has been performed. Using the simple neighbor-exclusion model of McGhee and von Hippel with the binding isotherm formula optimized for fitting errors, we found the binding constant K b and exclusion parameter n from the titration absorption spectra. It was shown that the binding parameters of porphyrins to DNA under acidic conditions are higher than those under physiological conditions. The K b of porphyrins with cancer DNA at pH 6.4 is an order of magnitude higher, and n is lower than that of healthy DNA at pH 7.4. The enhanced affinity of porphyrins for cancer DNA indicates that conformational alterations in the DNA structure create more-accessible binding sites. This selective interaction underscores the potential of porphyrins as effective agents for a targeted anticancer therapy.
More Related Videos
09:33Formation of Covalent DNA Adducts by Enzymatically Activated Carcinogens and Drugs In Vitro and Their Determination by 32P-postlabeling
Published on: March 20, 2018
10:05Genome-wide Mapping of Drug-DNA Interactions in Cells with COSMIC (Crosslinking of Small Molecules to Isolate Chromatin)
Published on: January 20, 2016
Related Concept Videos
Targeted Cancer Therapies
There are several types of targeted therapies against specific...
Inhibitors of Bacterial DNA Synthesis
Combination Therapies and Personalized Medicine
The combination of the drug acetazolamide and sulforaphane is a good example of combination therapy to treat cancer. The cells in the interior of a large tumor often die due to the hypoxic and...
Adaptive Mechanisms in Cancer Cells
Some of the advantages that cancer cells have on normal cells include - enhanced ability to divide without terminally differentiating, induce new blood vessel formation,...
Mutagenicity and Carcinogenicity