Sivanandham Vignesh

Publications (3)6.83 Total impact

• Article: DNA/RNA binding and anticancer/antimicrobial activities of polymer-copper(II) complexes.

  Jagadeesan Lakshmipraba, Sankaralingam Arunachalam, Anvarbatcha Riyasdeen, Rajakumar Dhivya, Sivanandham Vignesh, Mohammad Abdulkader Akbarsha, Rathinam Arthur James
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  ABSTRACT: Water soluble polymer-copper(II) complexes with various degrees of coordination in the polymer chain were synthesized and characterized by elemental analysis, IR, UV-visible and EPR spectra. The DNA/RNA binding behavior of these polymer-copper(II) complexes was examined by UV-visible absorption, emission and circular dichroism spectroscopic methods, and cyclic voltammetry techniques. The binding of the polymer-copper(II) complexes with DNA/RNA was mainly through intercalation but some amount of electrostatic interaction was also observed. This binding capacity increased with the degree of coordination of the complexes. The polymer-copper(II) complex having the highest degree of coordination was subjected to analysis of cytotoxic and antimicrobial properties. The cytotoxicity study indicated that the polymer-copper(II) complexes affected the viability of MCF-7 mammary carcinoma cells, and the cells responded to the treatment with mostly through apoptosis although a few cells succumbed to necrosis. The antimicrobial screening showed activity against some human pathogens.
  Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy 02/2013; 109C:23-31. · 2.10 Impact Factor
• Article: BSA binding and antimicrobial studies of branched polyethyleneimine-copper(II)bipyridine/phenanthroline complexes.

  Gopalaswamy Vignesh, Sankaralingam Arunachalam, Sivanandham Vignesh, Rathinam Arthur James
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  ABSTRACT: The interaction of two water soluble branched polyethyleneimine-copper(II) complexes containing bipyridine/phenanthroline with bovine serum albumin (BSA) was studied by, UV-Visible absorption, fluorescence, lifetime measurements and circular dichroism spectroscopic techniques. The polymer-copper(II) complexes strongly quench the intrinsic fluorescence of BSA is the static quenching mechanism through hydrogen bonds and van der Waal's attraction. The distance r, between the BSA and the complexes seems to be less than 2nm indicating that the energy transfer between the donor and acceptor occurs with high probability. Synchronous fluorescence studies indicate the binding of polymer-copper(II) complexes with BSA mostly changes the polarity around tryptophan residues rather than tyrosine residues. The circular dichroism studies indicate that the binding has induced considerable amount of conformational changes in the protein. The complexes also show some antibacterial and antifungal properties.
  Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy 05/2012; 96:108-16. · 2.10 Impact Factor
• Article: Antibiotic resistant pathogens versus human impacts: a study from three eco-regions of the Chennai coast, southern India.

  Sivanandham Vignesh, Krishnan Muthukumar, Rathinam Arthur James
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  ABSTRACT: We assessed the occurrence of pollution indicators and antibiotic resistant bacterial isolates from water and sediment samples of three different eco-regions of the Chennai coast between March - May of 2010. Total of 960 bacterial strains belonging to four genera were isolated which show the highest frequencies of resistance to vancomycin (53.6%) and penicillin (52.6%) (except Enterococcus sp., which is highly resistant to erythromycin) and lowest frequencies of resistance to chloramphenicol (3.43%), ciprofloxacin (3.95%), gentamicin (4.68%), and tetracycline (6.97%). The E. coli, Vibrio sp., Salmonella sp. and Enterococcus sp. show high frequency of resistance to 2-5 antibacterials of 60.4%, 45.83%, 69.16% and 46.6%, respectively. High pollution indices (PI - 6.66-14.06) and antibiotic resistance indices (ARI - 0.29-0.343) indicate that the coastal environment is highly exposed to antibiotic sources that suggesting to avoid direct contact.
  Marine pollution bulletin 02/2012; 64(4):790-800. · 2.63 Impact Factor