Antimicrobial activity on glass materials subject to disinfectant xerogel coating

G. J. COPELLO; S. TEVES; J. DEGROSSI; M. DAQUINO; M. F. DESIMONE; L. E. DÍAZ

JOURNAL OF INDUSTRIAL MICROBIOLOGY & BIOTECHNOLOGY

Springer

Año: 2006 vol. 33 p. 343 - 348

1367-5435

The antimicrobial compound dodecyl-di(aminoethyl)-glycine was immobilized in a silicon oxide xerogel matrix and used for glass surface coating. Coated glasses were tested for surface antimicrobial activity. The utilization of tetraethoxysilane (TEOS) as a silicon oxide polymer precursor, using the dip-coating process, allowed to generate transparent thin films over glass surfaces. Different concentrations of the antimicrobial compound were used to generate the coatings. The presence of dodecyl-di(aminoethyl)-glycine on coated and uncoated slides was analyzed by FT-IR spectra.             Coated glass slides were exposed to Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus suspensions for 24 hours. Then surface contamination was evaluated by the microbial plate count technique. When antimicrobial coated glasses were compared against antimicrobial-free coated glasses, the former showed over 99% reduction of colony-forming units (cfu) for Escherichia coli and Pseudomonas aeruginosa, when 1% of antimicrobial was present in the coating solution. The same percentage of reduction for Staphylococcus aureus was achieved when 1.5% of antimicrobial was present in the coating solution.             In the direct inhibition test on agar plates, no inhibitory zone is observed, indicating that the antimicrobial does not diffuse to the media.