title: Biochemical activity of a fluorescent dye rhodamine 6G: Molecular modeling, electrochemical, spectroscopic and thermodynamic studies.
abstract: Interaction of CT DNA with Rhodamine 6G (R6G) has been studied using molecular docking, electrochemical, spectroscopic and thermodynamic methods. From the study, it was illustrated that Rhodamine 6G binds to the minor groove of CT DNA. The binding was cooperative in nature. Circular voltametric study showed significant change in peak current and peak potential due to complexation. All the studies showed that the binding constant was in the order of 106M-1. Circular dichroic spectra showed significant conformational change on binding and DNA unwind during binding. Thermodynamic study showed that binding was favored by negative enthalpy and positive entropy change. From thermodynamic study it was also observed that several positive and negative free energies played significant role during binding and the unfavorable conformational free energy change was overcame by highly negative hydrophobic and salt dependent free energy changes. The experimental results were further validated using molecular docking study and the effect of structure on binding has been studied theoretically. From docking study it was found that the hydrophobic interaction and hydrogen bonds played a significant role during binding. The dye was absorbed by cell and this phenomenon was studied using fluorescent microscope. Cell survivability test showed that the dye active against Human Breast Cancer cells MDA-MB 468. ROS study showed that the activity is due to the production of reactive oxygen.
authors.affiliation: Department of Chemistry, Aliah University, Action Area IIA/27, New Town, Kolkata 700156, India.
authors.forename: Abdulla
authors.initials: A
authors.lastname: Al Masum
authors.affiliation: Department of Chemistry, Jadavpur University, Kolkata 700032, India.
authors.forename: Maharudra
authors.initials: M
authors.lastname: Chakraborty
authors.affiliation: Department of Chemistry, University College of Science, University of Calcutta, Kolkata 700009, India.
authors.forename: Soumen
authors.initials: S
authors.lastname: Ghosh
authors.affiliation: Department of Life science and Biotechnology, Jadavpur University, Kolkata 700032, India.
authors.forename: Dipranjan
authors.initials: D
authors.lastname: Laha
authors.affiliation: Department of Life science and Biotechnology, Jadavpur University, Kolkata 700032, India.
authors.forename: Parimal
authors.initials: P
authors.lastname: Karmakar
authors.affiliation: Department of Chemistry, Aliah University, Action Area IIA/27, New Town, Kolkata 700156, India. Electronic address: maidulaliah@gmail.com.
authors.forename: Md Maidul
authors.initials: MM
authors.lastname: Islam
authors.affiliation: Department of Chemistry, Jadavpur University, Kolkata 700032, India.
authors.forename: Subrata
authors.initials: S
authors.lastname: Mukhopadhyay
mesh_terms: D055664:Electrochemical Techniques; D005456:Fluorescent Dyes / Q000737:chemistry*; D008958:Models, Molecular; D012235:Rhodamines / Q000737:chemistry*; D013057:Spectrum Analysis; D013816:Thermodynamics
chemical_list: D005456:Fluorescent Dyes; D012235:Rhodamines; C026188:rhodamine 6G
keywords: CT DNA; Cell imaging; Cytotoxicity; Molecular modeling; Rhodamine 6G; Thermodynamic