title: Exploring the photochemosensitivity by novel cysteine-based mixed ligand complexes.
abstract: A new series of cysteine-based metal(II) complexes with 2,2'-bipyridine or 1,10-phenanthroline as co-ligand have been prepared and characterized. Their DNA binding and cleavage properties have been studied. The analytical and spectroscopic data of complexes 1-18 reveal that the complexes adopt an octahedral geometry around the central metal ion in which the cysteine is coordinated through NS and NN atoms, respectively. Spectroscopic titration and viscosity measurements reveal that the complexes bind to DNA through an intercalative mode. Electrophoresis measurements exhibit that they cleave pBR322 DNA efficiently in the presence of 3-mercaptopropionic acid (MPA), probably via hydrolytic mechanism with the involvement of (•)OH. The in vitro anticancer activities indicate that the Cu(II) complexes are active against four selected human tumor cell lines. Furthermore, it is remarkable that all the complexes exhibit significant photocytotoxicity against human breast cancer cell lines (MCF-7) with a potency more than the widely used drugs photofrin and cisplatin indicating that they have the potential to act as effective anticancer drugs in a dose-dependent manner.
authors.affiliation: Research Department of Chemistry, VHNSN College, Virudhunagar 626 001, Tamil Nadu, India.
authors.forename: Muthusamy
authors.initials: M
authors.lastname: Selvaganapathy
authors.affiliation: Research Department of Chemistry, VHNSN College, Virudhunagar 626 001, Tamil Nadu, India.
authors.forename: Narayanaperumal
authors.initials: N
authors.lastname: Pravin
authors.affiliation: Research Department of Chemistry, VHNSN College, Virudhunagar 626 001, Tamil Nadu, India.
authors.forename: Vellaichamy
authors.initials: V
authors.lastname: Muniyandi
authors.affiliation: Research Department of Chemistry, VHNSN College, Virudhunagar 626 001, Tamil Nadu, India.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Nazeer
authors.affiliation: Research Department of Chemistry, VHNSN College, Virudhunagar 626 001, Tamil Nadu, India. Electronic address: ramchem1964@gmail.com.
authors.forename: Natarajan
authors.initials: N
authors.lastname: Raman
mesh_terms: D000890:Anti-Infective Agents / Q000737:chemistry / Q000494:pharmacology; D002460:Cell Line; D018360:Crystallography, X-Ray; D003545:Cysteine / Q000737:chemistry*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D008024:Ligands; D008214:Lymphocytes / Q000187:drug effects; D055668:Photochemical Processes; D033362:Powder Diffraction; D013050:Spectrometry, Fluorescence; D014783:Viscosity
chemical_list: D000890:Anti-Infective Agents; D008024:Ligands; D003545:Cysteine
keywords: Cysteine; Hydrolytic mechanism; Intercalative mode; Photocytotoxicity