Skin permeation experiments have been broadly done since 1970s to 1980s as an evaluation method for transdermal drug delivery systems. In topically applied drug and cosmetic formulations, skin concentration of chemical compounds is more important than their skin permeations, because primary target site of the chemical compounds is skin surface or skin tissues. Furthermore, the direct pharmacolo...

Nicotine transdermal systems are being used as an aid to smoking cessation programs. As the kinetics of nicotine delivery is important in success of a smoking cessation program, rapid and high input of nicotine is required, which is not possible by passive methods and requires enhancement strategies such as iontophoresis. Iontophoretic permeation, of nicotine looks promising, based on published...

Many properties of chemicals depend on their stereochemistry. Among these, the effects of stereoisomerism on percutaneous absorption of drugs are not well studied. We have previously shown that permeation of tretinoin and isotretinoin (two geometric isomers) through hydrophilic enhancers-treated rat skin is stereoselective. As, depending on their lipophilicity, penetration enhancers can change ...

Many properties of chemicals depend on their stereochemistry. Among these, the effects of stereoisomerism on percutaneous absorption of drugs are not well studied. We have previously shown that permeation of tretinoin and isotretinoin (two geometric isomers) through hydrophilic enhancers-treated rat skin is stereoselective. As, depending on their lipophilicity, penetration enhancers can change ...

The permeation pathway of macromolecules and nanospheres through skin was evaluated using fluorescent isothiocyanate (FITC)-dextran (average MW, 4 kDa) (FD-4) and nanospheres (500 nm in diameter) in hairless rat abdominal skin and porcine ear skin as well as a three-dimensional cultured human skin model (cultured skin model). A low molecular hydrophilic compound, sodium fluorescein (FL) (MW, 37...

Preformulation studies on transdermal dosage forms involve liberal use of animal skin for assessing the permeation characteristics of drugs, influence of permeation enhancers, optimizing the formulation variables etc. The restricted availability of animal skin due to concerns regarding prevention of cruelty to animals has generated considerable interest in developing polymeric films for use as ...

Preformulation studies on transdermal dosage forms involve liberal use of animal skin for assessing the permeation characteristics of drugs, influence of permeation enhancers, optimizing the formulation variables etc. The restricted availability of animal skin due to concerns regarding prevention of cruelty to animals has generated considerable interest in developing polymeric films for use as ...

This study examined the efficacy of the percutaneous delivery of a tetramethylpyrazine-loaded microemulsion (TMP-ME) on skin pretreated with microneedles (MN). The TMP-ME formulation was optimized in vitro with skin permeation experiments, using a uniform experimental design, guided by a pseudo-ternary phase diagram, in which the TMP skin permeation level and mean particle size were indices. Th...

The purpose of this study was designed to investigate the in vitro and in vivo skin absorption of capsaicin and nonivamide from hydrogels. Various commercialized creams of capsaicin were also compared with hydrogels. Both skin stripping technique and Mexameter were applied to evaluate the level of capsaicin and nonivamide retained in stratum corneum (SC) and skin erythema in vivo. The partition...

Transdermal route offers inherent advantages over other conventional routes for the delivery of drugs with systemic activity. Transdermal drug delivery provides a continuous mode of administration at rates approaching zero-order similar to that provided by an intravenous infusion.The greatest obstacle is the stratum corneum, the outermost layer of the skin, which is considered to form a primary...