The effect of ultrasonic irradiation on the skin penetration of a potent humectant, sodium hyaluronate

Abstract

The effects of ultrasonic irradiation on the skin-moisturing and the skin penetration of sodium hyaluronate (HA) were measured in hairless rats. Ultrasound (2.15 MHz) with different power and pulse duty was applied for 10 min on the abdominal site which was pretreated with 1% HA for 3 h. Relative conductance on the skin surface was increased by the ultrasonication. The content of HA in the stratum corneum (measured using fluorescence-labeled HA) was also increased by the treatment. In addition, a good relationship was observed between the two values. The ultrasonic treatment may be utilized as a new tool to increase the HA penetration and the humectant efficacy into and on the skin surface.