Objective To study the influence of pulse mode on the electroporative fluxes of
tetracaine hydrochloride,a small molecule
ionic drug,through rat skin.Method Using side-by-side compartment cells,rat abdominal skin,
tetracaine hydrochloride as a model of small molecule ionic drugs, the effect of pulse mode on the in vitro electroporative fluxes of drug was investigated,and compared with passive diffusion and iontophoresis.Result The fluxes of tetracaine hydrochloride were obviously increased by electroporation(square wave pulses,pulse frequency: 40 pulses·min~(-1),pulse time: 0.4 s).The enhancing effect of electroporation was greater than iontophoresis(0.2 mA·cm~(-2),4 h).There were no obvious difference between the electroporative fluxes by total 400 pulses given at a time and those by total 400 pulses given twice.There were no obvious difference between the electroporative fluxes at 0.25 h or 0.75 h,by total 200 pulses given at a time and those by total 200 pulses given twice.From then on,there were obvious differences between them.The electroporative fluxes of tetracaine hydrochloride by total 200 pulses given at a time were greater than those by total 200 pulses given twice.Conclusion: The
percutaneous permeation of tetracaine hydrochloride was obviously increased by electroporation.The enhancing effect of electroporation was greater than iontophoresis.The influence of pulse mode on the fluxes of tetracaine hydrochloride was related to pulse number.