Dermal uptake of chemicals at the workplace may contribute considerably to the total internal exposure and so needs to be regulated. At present only qualitative warning signs--the "skin notations"--are available as instruments. An attempt was made to develop a quantitative dermal occupational exposure limit (DOEL) complementary to respiratory occupational exposure limits (OELs). The DOEL refers...

AIM The feasibility of transdermal delivery of naloxone, an opioid antagonist, by anodal iontophoresis patches using Ag/AgCl electrodes was investigated. METHODS To examine the effect of current strength, species variation and drug concentration on skin permeability of naloxone, in vitro skin permeation studies were performed using rat dorsal skin and porcine ear skin as the membrane. To dete...

Our previous study revealed that newborns had a high level of absorption of human milk a-lactalbumin. [1] It decreased during the first month in the whole and nonallergic infants showed a 4fold reduction of gut permeability at 25-30 days of life. But patients with early allergic symptoms have increased gut permeability in comparison to non-allergic infants. In this study we examined gut permeab...

Background Human skin exists in a wide range of different colors and gradations, ranging from white to brown to black. This is due to the presence of a chemically inert and stable pigment known as melanin, which is produced deep inside the skin but is displayed as a mosaic at the surface of the body. Methods & Materials In mammalian melanocytes, melanosome is a highly specialized organelle wh...

The absorption modulating activity of two alkylglycerol derivatives (batyl and chimyl alcohol) on skin barrier properties was evaluated. Biophysical tests such as transepidermal water loss (TEWL) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, as well as in vitro skin permeation studies, were performed in order to determine the effect of these compounds as c...

PURPOSE Classic penetration enhancement/retardation methods for improved dermal drug delivery primarily focus on co-applied chemicals aided alterations in skin accumulation/permeation profile, and in many cases, this has been achieved by compromising the systemic absorption/toxicities of penetrant/enhancer/retarder. In this study, higher dermal accumulation without systemic absorption of ketoro...

Topical ethanol is used as a dermal penetration enhancer in some commercial products. Previous studies have demonstrated that chronic ethanol consumption can also disrupt skin barrier function, leading to increased transdermal penetration. This observation becomes much more relevant if a single drinking episode induces similar changes. The purpose of this study was thus to examine the transderm...

A vehicle influences the concentration of penetrant within the membrane, affecting its diffusivity in the skin and rate of transport. Despite the huge amount of effort made for the understanding and modelling of the skin absorption of chemicals, a reliable estimation of the skin penetration potential from formulations remains a challenging objective. In this investigation, quantitative structur...

One of the main functions of the skin is to control the ingress and egress of water into and out of the body. The transport kinetics of water in the stratum corneum (SC), the dominant site of resistance in the skin, is normally described assuming a homogeneous membrane model. In the present work, the desorption of water from SC was studied and profiles obtained for amount desorbed versus time p...

In vitro percutaneous absorption of four antihypertensive drugs were carried out across the mice and human cavader skin in order to compare their skin permeability. An interesting trend was noticed in these experiments. Poorly water soluble drug prazosin hydrochloride showed 13 times enhanced flux in the mice skin whereas the steady-state flux of the water soluble drug propranolol hydrochloride...