Vehicle and enhancer effects on human skin penetration of aminophylline from cream formulations: Evaluation in vivo

Abstract

Sodium cocoyl isethionate (SCI) is an important surfactant ingredient in mild, syndet (synthetic detergent) cleansing bars. In vitro and in vivo studies have demonstrated that SCI is mild and less damaging to the skin barrier than soaps and surfactants such as sodium dodecyl sulfate (SDS). We have recently shown that SDS forms small micelles in aqueous solutions contacting the skin relative to the aqueous pores in the stratum corneum (SC), and as a result, the SDS micelles can contribute to SDS skin penetration and induce skin barrier perturbation. In this paper, we attempt to explain the well-documented skin mildness of SCI by examining the size of the SCI micelles relative to that of the aqueous pores in the SC. For this purpose, we have conducted in vitro mannitol skin permeability and average skin electrical resistivity measurements upon exposure of the skin to an aqueous SCI contacting solution in the context of a hindered-transport aqueous porous pathway model of the SC. These in vitro studies demonstrate that an SCI micelle of radius 33.5 ± 1 Å (as determined using dynamic light-scattering measurements) experiences significant steric hindrance and cannot penetrate into the SC through aqueous pores that have an average radius of 29 ± 5 Å .We believe that this inability of the SCI micelles to contribute to SCI skin penetration and associated skin barrier perturbation is responsible for the observed skin mildness of SCI. Through in vitro quantitative skin radioactivity assays using 14 C-radiolabeled SCI and pig full-thickness skin (p-FTS), we also show conclusively that SCI skin penetration is dose-independent, an important finding that provides additional evidence that the larger SCI micelles cannot penetrate into the SC through the smaller aqueous pores that exist in the SC, and therefore, cannot induce skin barrier perturbation.The effects of four essential oils (rosemary, ylang, lilacin, and peppermint oils), and three plant oils (jojoba oil, corn germ oil, and olive oil) on the permeation of aminophylline were studied using human skin. The permeation effects of these oils were compared with those of three chemical penetration enhancers. Although, all oils enhanced the permeation of aminophylline, their effects were less than that of ethanol. Jojoba oil was found to be the most active, causing about a 32% peak height decrease of N-H bending absorbances in comparison with the control, while peppermint, lilacin, rosemary, and ylang oils caused 28%, 24%, 18%, and 12% peak height decreases, respectively. Microemulsions containing 10% jojoba oil and 30% corn germ oil were found to be superior vehicles for the percutaneous absorption of aminophylline. Comparision with results obtained from highperformance liquid chromatography shows good agreement.In vitro dermal absorption and metabolism of D&C red no. 17 in human and porcine skin

Essential oils and their constituents as skin penetration enhancer for transdermal drug delivery: a review

“…Hydrogel with 1 % ibuprofen and 3% turpentine oil showed a maximum flux of 10.87 mg/cm 2 /h across artificial skin and 17.26 mg/cm 2 /h across rabbit abdominal skin [36] Rosemary, ylang, lilacin, peppermint oils aminophylline human skin All oils enhanced the permeation of aminophylline but their effects were less than that of ethanol as enhancer [37] Ylang, lavender, orange, nutmeg, chamomile, sage, eucalyptus, ginger, peppermint oils p-aminobenzoic acid human skin Levels of p-aminobenzoic acid and its metabolites were higher in the urine of the participants treated with essential oils than in the urine of the untreated controls [38] Basil oil labetolol hydrochloride rat abdominal skin Basil oil is proposed as a promising penetration enhancer for improved transdermal drug delivery of labetolol hydrochloride [32] Tulsi, turpentine oils flurbiprofen rat skin Bioavailability of flurbiprofen with reference to orally administered flurbiprofen in rats was found to increase by 2.97, 3.80 and 5.56 times with transdermal patch formulation without enhancer, 5% (v/v) tulsi and turpentine oil formulations, respectively [24] Eryngium bungei essential oil piroxicam rat skin Essential oil in 5 % w/w, providing an almost 9.17-fold increase in permeability coefficient of piroxicam [39] Fennel, eucalyptus, citronella, mentha oils trazodone hydrochloride mouse epidermis Percutaneous penetration flux for trazodone hydrochloride was increased with skin pretreatment by 10% essential oils in the following order: fennel oil > eucalyptus oil > citronella oil > mentha oil [40] Ajuput, niaouli, cardamom, orange, melissa, myrtle oils estradiol hairless mouse skin Niaouli oil (10 % w/w) was the best permeation promoter for estradiol among all tested essential oils Between main terpenes components of niaouli (1,8 cineole, α-pinene, α-terpineol, [41] Niaouli oil estradiol hairless mouse skin…”

Effects of Various Penetration Enhancers on Penetration of Aminophylline Through Shed Snake Skin

“…It has been suggested that aminophylline inhabits the activity of certain hormones that cause fat storage followed by release of intercellular triglycerides. It seems that aminophylline blocks the receptors for these hormones located on fat cells (1, 2, 9). The transdermal method is used as one of systemic drug delivery routes with several advantages such as avoidance of first-pass effect, ease of use, ability to control drug delivery for a longer time compared to usual gastrointestinal transit of oral form, and is associated with patient compliance.…”

Epidermolysis bullosa: a case report

“…15 Studies also have shown that jojoba oil facilitates cutaneous penetration of active ingredients. 16,17 conditions, patient adherence to therapy, and the economic burden of chronic wounds. The manuscript management system is completely online and includes a very quick and fair peer review system, which is all easy to use.…”