title: Evaluation of tetraethoxysilane (TEOS) sol-gel coatings, modified with green synthesized zinc oxide nanoparticles for combating microfouling.
abstract: Green synthesis of zinc oxide nanoparticles (ZnO-NPs) is gaining importance as an eco-friendly alternative to conventional methods due to its enormous applications. The present work reports the synthesis of ZnO-NPs using the endosperm of Cocos nucifera (coconut water) and the bio-molecules responsible for nanoparticle formation have been identified. The synthesized nanoparticles were characterized using UV-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and Zeta potential measurement. The results obtained reveal that the synthesized nanoparticles are moderately stable with the size ranging from 20 to 80 nm. The bactericidal effect of the nanoparticles was proved by well diffusion assay and determination of minimum inhibitory concentration (MIC) against marine biofilm forming bacteria. Further the green synthesized ZnO-NPs were doped with TEOS sol-gels (TESGs) in order to assess their antimicrofouling capability. Different volumes of liquid sol-gels were coated on to 96-well microtitre plate and cured under various conditions. The optimum curing conditions were found to be temperature 60 °C, time 72 h and volume 200 μl. Antiadhesion test of the undoped (SG) and ZnO-NP doped TEOS sol-gel (ZNSG) coatings were evaluated using marine biofilm forming bacteria. ZNSG coatings exhibited highest biofilm inhibition (89.2%) represented by lowest OD value against Pseudomonasotitidis strain NV1.
authors.affiliation: Bioremediation Lab, School of Biosciences and Technology, VIT University, Vellore 632014, Tamil Nadu, India.
authors.forename: A Nithya Deva
authors.initials: AN
authors.lastname: Krupa
authors.affiliation: Bioremediation Lab, School of Biosciences and Technology, VIT University, Vellore 632014, Tamil Nadu, India. Electronic address: vimala.r@vit.ac.in.
authors.forename: R
authors.initials: R
authors.lastname: Vimala
mesh_terms: D018441:Biofilms / Q000187:drug effects; D016972:Enterobacter cloacae / Q000187:drug effects / Q000502:physiology; D005782:Gels / Q000737:chemistry*; D055772:Green Chemistry Technology; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000633:toxicity; D008826:Microbial Sensitivity Tests; D008855:Microscopy, Electron, Scanning; D010316:Particle Size; D011549:Pseudomonas / Q000187:drug effects / Q000502:physiology; D012821:Silanes / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D041181:Staphylococcus hominis / Q000187:drug effects / Q000502:physiology; D013696:Temperature; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D005782:Gels; D012821:Silanes; C040733:tetraethoxysilane; D015034:Zinc Oxide
keywords: Antimicrofouling; Cocos nucifera; Green-synthesis; Marine biofilm; Sol–gel coating; ZnO-NPs