Spectroscopic characterization of thiazole orange-3 DNA interaction
Journal article, 2008

The interaction of a new derivative of thiazole orange (TO-3) with calf thymus DNA (ctDNA) has been investigated by fluorescence and absorption spectroscopy. When TO-3 binds to ctDNA, absorption bands exhibit significant hypochromicity at low base pair/dye ratio (BP/D ratio), and high BP/D show hyperchromicity with red shift. The spectral changes are attributed to the different species formed between TO-3 and ctDNA in the titration course of the dye molecule with DNA. Multivariate curve resolutions-alternating least squares (MCR-ALS) is applied to the absorption measurements recorded to recover the concentration profiles and the pure spectra of the DNA/TO-3 complexes involved in the process. The binding constant and size of the binding site have been determined spectrophotometrically using the McGhee von Hippel equation. MCR-ALS has been used to reveal the precise concentration profiles of all detectable species formed between ctDNA and TO-3 and their pure spectral profiles. © 2008 Humana Press Inc.


J. Ghasemi

Razi University

S. Ahmadi

Razi University

Ashraf Ahmad

Chalmers, Chemical and Biological Engineering

S. Ghobadi

Razi University

Applied Biochemistry and Biotechnology

0273-2289 (ISSN)

Vol. 149 1 9-22

Subject Categories

Industrial Biotechnology



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