OBJECTIVETo evaluate the transdermal permeability of glucosamine sulfate solution across ex vivo rabbit dermis under ultrasound and optimize the ultrasound conditions.

METHODSThe ultrasound-assisted transdermal permeation of glucosamine sulfate solution across ex vivo rabbit dermis was tested using a simple Franz diffuse. The transdermal permeation volume and rate were calculated by measuring the concentration of glucosamine sulfate in the receptor fluid with ultraviolet spectrophotometry, and the impact of different sound intensities, irradiation time and solution concentration on solution permeation was analyzed.

RESULTSAt the ultrasound intensity of 0.2 W/cm(2), the permeation volume and rate of glucosamine sulfate both reached the maximum; no glucosamine sulfate was detected in the receptor fluid after a 5-min ultrasound irradiation. The permeation volume and rate of glucosamine sulfate increased as the irradiation time prolonged and also with increased glucosamine sulfate concentration. The dorsal and lateral skin thickness (2.0∓0.1 and 1.2∓0.1 mm, respectively) did not significantly affect the transdermal permeation of glucosamine sulfate (P>0.05).

CONCLUSIONUltrasound irradiation at 1.0 MHz for over 5 min allows glucosamine sulfate to permeate rabbit dermis, and the volume and rate of permeation increase with the irradiation time and concentration of the solution and are not affected by variations of the dermal thickness.