Objective: To compare the antimicrobial effect of five brands of hand sanitizer against Staphylococcus aureus.
Design: Comparative research design.
Settings: This study was conducted at Cebu Doctor`s University- College of Medicine (CDU-CM) Microbiology Laboratory at Osmena Boulevard, Cebu City.
Subject: A standard pure culture of Staphylococcus aureus ATCC #3573 was used as the study and was tested with five brands of hand sanitizers.
Procedures: Staphylococcus aureus was streaked in three blood agar plates (BAP) using four quadrant streaking and these were incubated at 30-35 degrees celcius for 24 hours. After incubation, the bacteria was transferred to a 0.85% sterile saline solution until 0.5 McFarland turbidity was obtained. The suspension of bacteria was swabbed to a 4% Mueller Hinton Agar (NHA) using overlap streaking method. this was incubated for 24 hours. Two MHA plates were used for each brand of hand sanitizer and for the positive and negative controls. For each MHA plate, five wells were dug. The sanitizers or the positive and negative controls were then placed in the wells. In the wells of the two MHA plates, the positive control was placed. In another two MHA plates, The same thing was done using the negative control. For each of the five brands of hand sanitizers, two MHA plates were also used. The five brands of hand sanitizers were placed in their respective wells. Then all these plates were incubated at 30-35 degrees celcius for 24 hours. After the 24 hours incubation, the zones of inhibition were measured using a vernier caliper.
Research Instrument/Measures: A vernier caliper was used to measure the zones of inhibition. a data sheet was used where the following data were recorded: zones of inhibition, mean standard deviation, interpretation of the zones of inhibition produced by the five brands of hand sanitizers and the positive and negative controls.
Results: The results of the study were the following: the positive control showed a mean zone of inhibition of 0.98mm. The groups that had greater zones of inhibition than the positive control were the Group E sanitizer with a mean zone of inhibition of 3.65mm and Group B with mean zone of inhibition of 3.12mm. The three other hand sanitizers, Brand a with a mean zone of inhibition of 0.98mm, Brand c with a mean zone of inhibition of 0.70mm, and Brand D with a mean zone of inhibition of 0.72mm, showed less mean zone of inhiition than the positive control but still had greater inhibition than the negative control which had a mean zone of inhibition of 0.00mm. The computed F value which was 359.76 was greater than the critical value which was 2.25 indicating that there was a significant difference among the seven groups and rejecting the null hypothesis. The negative control as compared with each of the five brands showed a significant difference. When each of the five brands were compared with the positive control the only group that did not show significant difference was Brand A.
Conclusion: Of the five brands of hand sanitizers, only two brands (B and E) showed greater antimicrobial effect than the positive control based on the zones of inhibition. Brand E had the greatest zone of inhibition in terms of the size of diameter, indicating that brand E had the greatest antimicrobial effect. The other brands, a, C and D, had less antimicrobial effect as compared with the positive control.