Permeation Studies Comparing Cobra Skin with Human Skin Using Nicotine Transdermal Patches

Abstract

Cobra skin (Naja Naja Khaotia) was used as a barrier for an in vitro permeation study using nicotine. Fluxes of nicotine that permeated from Nicotinell through cobra skin (CS) taken from the head, body, and tail were 233.93 +/- 16.08, 206.87 +/- 19.00, and 211.26 +/- 22.93 micrograms/cm2/hr1/2, respectively (n = 6). This indicated no significant difference (p > .05). Abdominal human epidermis (HE), obtained from cadavers, and the CS provided identical permeation kinetics for nicotine, which can be described by Mt = 4M alpha (Dt/pi L2)1/2. The mean flux of nicotine formulated as an acrylic transdermal patch that permeated through HE was 137.92 +/- 67.79 micrograms/cm2/hr1/2 (4 specimens, n = 12), whereas that through CS was 180.13 +/- 41.05 micrograms/cm2/hr1/2 (4 specimens, n = 15). The ratio of the fluxes of nicotine from formulated patches having three different nicotine contents using CS and HE was 1.22 to 1, respectively, for each of the patches irrespective of nicotine content. The coefficients of variation of the nicotine permeated were 22.79% and 49.15% for CS and HE, respectively, that is, a narrower variation of results was obtained with CS. This indicated that CS could be used for nicotine permeation studies.

Shed king cobra and cobra skins as model membranes for in-vitro nicotine permeation studies

“…Inter-specimen variation of human epidermis was higher than that of shed snake skin. This result was similar to previous reports (Southwell et al 1984 ;Pongjanyakul et al 2000). Human skin had greater inter-specimen variation because of the variation of hair follicles (Bialik et al 1993) and the thickness of epidermis (Whitton & Everall 1973).…”

“…This indicated that the matrix skin system formed a single homogenous polymeric ® lm. The results were similar to those using whole cobra skin as a membrane in a previous study (Pongjanyakul et al 2000). The equation used to describe the transport of nicotine across the three types of membrane is as follows (Kydonieus 1987):…”

“…A nicotine transdermal patch was prepared and evaluated in our laboratory. The patch was shown to be an eOE ective device for nicotine delivery in permeation studies using human skin and whole cobra skin as barrier membranes (Pongjanyakul et al 2000). Shed snake skin may be an alternative to animal skin since it can be obtained periodically and repeatedly from the same snake without injury to the snake.…”

Influence of magnesium aluminium silicate on rheological, release and permeation characteristics of diclofenac sodium aqueous gels in-vitro

“…Cobra skin was used as a barrier membrane for the DS permeation studies because one snake skin provides enough material for a complete study, with low intraspecimen variation (Pongjanyakul et al 2000). The whole skin of a cobra (Naja Naja Khaotia) was obtained within 24 h after its natural death from the Snake Farm, Thai Red Cross, Bangkok, Thailand.…”

Liberação e permeação dérmica \"in vitro\" de hidrogel de cafeína em comparação ao uso de papaína como promotora de permeação

“…Existe, também, uma terceira e última camada de alfa-queratina mais interna. A camada intermediária é subdividida em três subcamadas de estrutura multilamelar com células cornificadas (alfa-queratina), ao redor dos lipídeos intercelulares, representando, assim, o principal depósito de lipídeos, sendo considerada a maior barreira para a penetração da água (Pongjanyakul et al, 2000).…”