[In vitro antimicrobial activity of glutaraldehyde plus O-phenylphenol association (ratio 2:1)]

The correct use of antiseptics, disinfectants and sterilization processes to inactivate or remove micro-organisms is an essential component of an effective infection control program. To reach this result the use of phenolic detergent-disinfectants which work well as a presoak has always been suggested in lieu of sterilization involving submerging instruments in a properly prepared glutaraldehyde solution for about 6 to 10 hrs. This study investigated the in vitro effectiveness of disinfectant solution containing 2% glutaraldehyde and 1% o-phenylphenol.

The organisms used were purchased from the American Type Culture Collection (Escherichia coli ATCC 25922, Candida albicans ATCC 10231, Pseudomonas aeruginosa ATCC 27853, Staphylococcus aureus ATCC 25923, Staphylococcus epidermidis ATCC 12228), and from our clinical collection (Proteus mirabilis CH 14, Klebsiella oxytoca CH 22, Serratia liquefaciens CH 90). MIC and MBC were evaluated as testing solution for antimicrobial activity. The contact time studied between disinfectant and bacteria were 30 sec, 1, 2, 5, 10, 20 and 30 min.

The results showed that MIC values for most bacteria were 3.75 mg/ml. The MBC values were similar or higher than the MIC. The disinfectant solution killed E. coli and C. albicans already after 10 min, but for S. aureus 30 min was necessary.

This study proved that this solution attained the sterilization of surgical instruments in good timing and at low cost.