These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Multivariate spectrochemical analysis of interactions of three common Isatin derivatives to calf thymus DNA in vitro.
    Author: Shahbazy M, Pakravan P, Kompany-Zareh M.
    Journal: J Biomol Struct Dyn; 2017 Sep; 35(12):2539-2556. PubMed ID: 27593978.
    Abstract:
    Interactions of Isatin and its derivatives, Isatin-3-isonicotinylhydrazone (IINH) and Isatin-β-thiosemicarbazone (IBT), with calf thymus DNA (ctDNA) have been investigated to delineate pharmaceutical-physicochemical properties using UV-Vis/fluorescence/circular dichroism (CD) spectroscopy, viscosity measurements, and multivariate chemometrics. IINH and IBT molecules intercalate between base pairs of DNA, hypochromism in UV absorptions, increase in the CD positive band, sharp increase in specific viscosity, and the displacement of the methylene blue and Neutral Red dye in complexes with ctDNA, by the IINH and IBT molecules, respectively. The observed intrinsic binding constants (Kb[IBT-ctDNA] = 1.03 × 105 and Kb[IINH-ctDNA] = 1.09 × 105 L mol-1) were roughly comparable to other intercalators. In contrast, Isatin binds with ctDNA via groove mode (Kb[Isatin-ctDNA] = 7.32 × 104 L mol-1) without any significant enhancement in ctDNA viscosity. The fluorescence quenching of Isatin by ctDNA was observed as static. CD spectra indicated that Isatin effectively absorbs into grooves of ctDNA, leading to transition from B to C form. Thermodynamic parameters like enthalpy changes (∆H < 0) and entropy changes (∆S > 0) were calculated according to Van't Hoff's equation, indicating the spontaneous interactions. The common soft/hard chemometric methods were used not only to resolve pure concentration and spectral profiles of components using the acquired spectra but also to calculate Stern-Volmer quenching constants, binding stoichiometry, apparent binding constants (Ka), binding constants (Kb), and thermodynamic parameters. The Kb values for Isatin, IINH, and IBT were calculated as 9.18 × 103, 1.53 × 105, and 2.45 × 104 L mol-1, respectively. The results obtained from experimental-spectroscopic analyses showed acceptable agreement with chemometric outlines.
    [Abstract] [Full Text] [Related] [New Search]