<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Tocopherol represents a big challenge for transdermal permeation owing to its extreme hydrophobicity and large molecular mass. The aim of the present study was to develop alpha-tocopherol (T) topical formulations and evaluate their ex vivo and in vivo permeation. Franz diffusion cells were used for ex vivo permeation, and neonatal rats were used for in vivo permeation. Seven gel formulations and 21 liquid formulations were investigated for physical stability, viscosity and permeation of T. Analysis of T was performed by a validated HPLC method using a UV detector. The ex vivo permeation from gel and emulsion formulations was very poor (0.001-0.015 %). Highest permeation was observed from monophasic liquid formulations containing dimethyl sulfoxide (DMSO), tocopheryl polyethylene glycols (TPGs), propylene glycol, ethanol and 9.5 % T. The in vivo results demonstrated higher retention in the epidermis compared to subcutaneous tissues, 1377 and 1.13 μg g<sup>-1</sup>, respectively. Increasing T concentration from 4.8 to 9.5 % did not increase the amount permeated or % of T retained. It was concluded that simple solutions of T in the presence of DMSO and TPGs were more promising systems for effective transdermal permeation compared to gel, emulsion or oleaginous systems.</p></abstract>

Tocopherol represents a big challenge for transdermal permeation owing to its extreme hydrophobicity and large molecular mass. The aim of the present study was to develop alpha-tocopherol (T) topical formulations and evaluate their ex vivo and in vivo permeation. Franz diffusion cells were used for ex vivo permeation, and neonatal rats were used for in vivo permeation. Seven gel formulations and 21 liquid formulations were investigated for physical stability, viscosity and permeation of T. Analysis of T was performed by a validated HPLC method using a UV detector. The ex vivo permeation from gel and emulsion formulations was very poor (0.001-0.015 %). Highest permeation was observed from monophasic liquid formulations containing dimethyl sulfoxide (DMSO), tocopheryl polyethylene glycols (TPGs), propylene glycol, ethanol and 9.5 % T. The in vivo results demonstrated higher retention in the epidermis compared to subcutaneous tissues, 1377 and 1.13 μg g-1, respectively. Increasing T concentration from 4.8 to 9.5 % did not increase the amount permeated or % of T retained. It was concluded that simple solutions of T in the presence of DMSO and TPGs were more promising systems for effective transdermal permeation compared to gel, emulsion or oleaginous systems.

Development of Novel Formulations to Enhance in Vivo Transdermal Permeation of Tocopherol

Department of Pharmaceutics Faculty of Pharmacy Kuwait University, Kuwait

Department of Pharmaceutics Faculty of Pharmacy Kuwait University, Kuwait/Current address: Kuwaiti Saudi Pharmaceutical Company (KSPICO), Kuwait

Acta Pharmaceutica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Tocopherol represents a big challenge for transdermal permeation owing to its extreme hydrophobicity and large molecular mass. The aim of the present study was...

Development of Novel Formulations to Enhance in Vivo Transdermal Permeation of Tocopherol

Published Online: Oct 08, 2014

Page range: 299 - 309

Accepted: May 26, 2014

DOI: https://doi.org/10.2478/acph-2014-0021

Keywords
tocopherol, topical formulation, chemical analysis, ex vivo and in vivo, skin barrier

© by Aly H. Nada

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Development of Novel Formulations to Enhance in Vivo Transdermal Permeation of Tocopherol

Published Online: Oct 08, 2014

Page range: 299 - 309

Accepted: May 26, 2014

DOI: https://doi.org/10.2478/acph-2014-0021

Keywordstocopherol, topical formulation, chemical analysis, ex vivo and in vivo, skin barrier

© by Aly H. Nada

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
tocopherol, topical formulation, chemical analysis, ex vivo and in vivo, skin barrier