Biophysical studies on the base specificity and energetics of the DNA interaction of photoactive dye thionine: Spectroscopic and calorimetric approach

Studying non-covalent drug–DNA interactions

“…Various thermodynamic parameters of the interaction are easily obtained directly or indirectly and the mechanism can be easily elucidated. ITC measures the heat absorbed or released during the interaction and calculates various parameters like binding sites (n), association constant (K), change in enthalpy (DH) and change in entropy (DS) [13,[66][67][68], which are used to decipher the binding interaction and binding mode. For example, a large negative enthalpy of binding along with positive entropy is typical for an interaction of small molecule with DNA [69].…”

Silver Nanoparticles – Universal Multifunctional Nanoparticles for Bio Sensing, Imaging for Diagnostics and Targeted Drug Delivery for Therapeutic Applications

“…Plasmid pCDNA-GFP was studied in terms of their degree of adsorption on montmorillonite, silver nanoparticles stabilized with montmorillonite clay, starch, citrate, polylysine and multiwalled carbon nanotubes [ Figure 7]. DNA molecules are net negatively-charged, and they can adsorb to net positively-charged surfaces, such as the edges of clay minerals (Nath et al, 2007) as well as to net negativelycharged surfaces, such as the surfaces of clays, by electrostatic bridges with the water of hydration of charge-compensating cations (Paul et al, 2010). Under acidic conditions (generally below pH 5), DNA becomes positively charged by protonation of adenine and cytosine, followed by guanine, and by protonation of the negative charges of phosphate groups.…”

Spectroscopic Studies of the Binding Interactions of Phenothiazininum Dyes (Thionine Acetate, Azure A and Azure B) with Calf-thymus DNA

“…It is also a good singlet oxygen generator and used in Photodynamic Therapy (PDT) [4,5]. The interaction studies of thionine acetate with the DNA molecule under various conditions have been well reported [6,7]. It is extensively used in nucleic acid probes [1], decontamination of blood products [8], and against bacteria, viruses, and yeast [9][10][11].…”