Transdermal delivery of diclofenac sodium gel after iontophoresis / 浙江大学学报·医学版

ABSTRACT

OBJECTIVE: To observe the in vivo effect of combined iontophoresis and laurocapram pretreatment on transdermal delivery of diclofenac sodium gel. METHODS: Diclofenac sodium gel was prepared using polyvinyl alcohol, carboxymethylcellulose sodium and hydroxypropylmethyl cellulose. The diclofenac blood level in rabbits was measured in four groups passive diffusion, laurocapram pretreatment, iontophoresis (current density controlled at 0.3 mA/cm(2)) and combined laurocapram pretreatment and iontophoresis. Rabbit stratum corneum of each of the four groups was examined using a scanning electron microscope. RESULTS: Diclofenac blood concentration in the passive diffusion group was undetectable. The diclofenac blood concentration area under the curve compared with time was 8.4 &mgr;l ml(-1) h(-1) in the laurocapram pretreatment group, 2.7 &mgr;l ml(-1) h(-1) in the iontophoresis group and 15.4 &mgr;l ml(-1) h(-1) in the combination group. There was no detectable damage observed by scanning electron microscopyto the stratum corneum after iontophoresis or laurocapram pretreatment. CONCLUSION: The combination of iontophoresis and laurocapram pretreatment appears to enhance transdermal delivery of diclofenac sodium gel wi thout significant skin damage.