The effect of phonophoresis on transdermal delivery of sinomenine hydrochloride gel in vitro / 中华物理医学与康复杂志

ABSTRACT

Objective To study the effect of phonophoresis on transdermal delivery of sinomenine hydrochloride ( SH ) gel in vitro. Methods Ultrasound at one of two frequencies ( 800 kHz or 1 MHz) was applied with a sonicator with a transducer in this study. The skin of male Sprague-Dawley rats was used as the model and SH gel was used as the ultrasound couplant. The permeation rate of SH was detected using a modified Franz diffusion cell maintained at 32±0.5℃ and filled with 20% polyethylene glycol 400 physiological saline solution. The transdermal phonophoresis experiments were carried out in five groups Group Ta, f=800 kHz, / = 0.75 W/cm2, t = 10 minGroup Tb,f=1 MHz,I=0.7 W/cm2, t=10 min; Group Tc,f=1 MHz,I=0.35 W/cm2, t=10 min; Group Td,f=800 kHz, I = 1.5 W/cm2, t = 10 min and Group Tc,f=800 kHz, I=1.5 W/cm2,t=5 min. There was also a control group (C) in which the SH was allowed to diffused passively. Samples were withdrawn at the indicated intervals and the concentration of SH was determined by high-performance liquid chromatography. The transdermal parameters such as average accumulated delivery quantity per unit area Q8h, average transdermal steady delivery rate J, and Tlag were calculated. Results The Q8h and Js of the control group were 20.65±10.23 μ/cm2 and 3.02±0.11μ/cm2/h respectively. The phonophoresis parameters in groups Ta and Tb were, on average, significantly higher than in the control group. The parameters in group Tb were significantly larger, on average, than in Te. In group Td the parameters were significantly larger than in groups Ta and Te. Conclusions The results show that phonophoresis can enhance the transdermal delivery of SH. Phonophoresis variables such as frequency and time influence its effects on drug permeation. Almost no change was observed in the structure of the skin after phonophoresis, though under a scanning electron microscope the surface of the corneum appeared rough and porous. Phonophoresis is there-fore an effective and safe method for SH transdermal delivery, and the effect is positively relation with the applied intensity and exposure time.