[Evaluating the effects of dual frequency sonication parameters on acoustic cavitation by chemical dosimeter using iodide]

Production of acoustic cavitation by sonication has been recently recommended as a targeted treatment. The experimental results from studies indicate that the activity of cavitation generated by bi- or multi-frequency ultrasound irradiation is higher than that caused by single frequency irradiation. In this study, effects dual [1 MHz and 40 kHz] and single frequency sonication on acoustic cavitation were investigated by chemical dosimeter using iodide. In this study, we investigated the exposure parameters in low level dual-frequency ultrasound in near fields of 40 kHz and 1 MHz in the progressive wave mode by chemical dosimeter using iodide. Finally, the effective protocol for enhancement of the inertial cavitation activity was determined. It has been shown that the dosimeter absorbance in the continuous mode sonication is more than the pulse mode. Moreover, significant correlations were found between the time and intensity of single and dual frequency sonication and the iodide dosimeter absorbance. In constant energy, inertial cavitation activity in the pulse mode remained approximately constant. Among different combinations, the combined ultrasound sonication in continuous mode could produce a more remarkable enhancement of the inertial cavitation activity [1.78 times] than the algebraic sum. Simultaneous combined dual frequency sonication is more effective than single frequency sonication in producing the inertial cavitation activity

Viability of lactobacillus acidophilus in various vaginal tablet formulations

The lactobacilli which are present in vaginal fluids play an important role in prevention of vaginosis and there are considerable interests in formulation of these friendly bacteria into suitable pharmaceutical dosage forms. Formulating these microorganisms for vaginal application is a critical issue as the products should retain viability of lactobacilli during formulation and also storage. The aim of this study was to examine the viability and release of Lactobacillus acidophilus from slow-release vaginal tablets prepared by using six different retarding polymers and from two effervescent tablets prepared by using citric or adipic acid. The Carbomer-based formulations showed high initial viablility compared to those based on HPMC-LV, HPMC-HV, Polycarbophil and SCMC polymers which showed one log decrease in viable cells. All retarding polymers in slow release formulations presented a strong bacterial release at about 2 h except Carbomer polymers which showed to be poor bacterial releasers. Although effervescent formulations produced a quick bacterial release in comparison with polymer based slow-release tablets, they were less stable in cold storage. Due to the strong chelating characteristic of citric acid, the viability was quickly lost for aqueous medium of citric acid in comparison with adipic acid based effervescent tablets