TREATMENT OF BACTERIAL BIOFILMS ON POLYMERIC BIOMATERIALS USING ANTIBIOTICS AND ULTRASOUND

New studies on the effect of frequency and duration of exposure upon t he ultrasonic enhanced action of gentamicin against biofilms of Escher ichia cell are presented in this paper. Ultrasound was applied at clin ical levels which would not harm human tissue. The study on frequency indicated that lower frequencies produce higher levels of killing. The results of the timed experiment indicate that complete sterilization of a 14-h biofilm can be achieved after 6 h of exposure. These finding s are significant because they show that biofilms can be reduced to ze ro reproductive ability as assessed by plate counting.