Article

Chemical enhancers for the absorption of substances through the skin: Laurocapram and its derivatives.

División de Estudios de Posgrado (Tecnología Farmacéutica), Facultad de Estudios Superiores Cuautitlán, Universidad Nacional Autónoma de México, Cuautitlán Izcalli, Edo. de México.
Drug Development and Industrial Pharmacy (impact factor: 1.49). 04/2006; 32(3):267-86. DOI:10.1080/03639040500518708 pp.267-86
Source: PubMed

ABSTRACT Absorption enhancers are substances used for temporarily increasing a membrane's permeability (e.g., the skin and mucosa), either by interacting with its components (lipids or proteins) or by increasing the membrane/vehicle partition coefficient. This article presents the results of biophysical and permeability studies performed with Laurocapram and its analogues. As shown, Laurocapram and its analogues present different enhancing efficacies, for most of both hydrophilic and lipophilic substances. The enhancing effect of Laurocapram (Azone) is attributed to different mechanisms, such as insertion of its dodecyl group into the intercellular lipidic bilayer, increase of the motion of the alkylic chains of lipids, and fluidization of the hydrophobic regions of the lamellate structure. Toxicological studies reveal a low toxicity for Laurocapram, and for some derivatives, a relationship exists between toxicity and the number of carbons in the alkylic chain. Very important, when applied to human skin, Laurocapram shows a minimal absorption, being quickly eliminated from circulation. However, although Laurocapram and its derivatives have been shown to provide enhancement, they have not been widely accepted because of their suspected pharmacological activity or questions about their safety.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

Absorption enhancers
 
alkylic chain
 
alkylic chains
 
analogues present different
 
derivatives
 
different mechanisms
 
enhancing effect
 
human skin
 
hydrophilic
 
hydrophobic regions
 
insertion
 
intercellular lipidic bilayer
 
lamellate structure
 
lipids
 
lipophilic substances
 
low toxicity
 
membrane's permeability
 
membrane/vehicle partition coefficient
 
minimal absorption
 
suspected pharmacological activity