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Planta Med 2012; 78(4): 354-361
DOI: 10.1055/s-0031-1280431
Pharmacokinetic Investigations
Original Papers
© Georg Thieme Verlag KG Stuttgart · New York

Investigating the Effect of Aloe vera Gel on the Buccal Permeability of Didanosine

Elizabeth Ojewole1 , Irene Mackraj2 , Kamil Akhundov3 , Josias Hamman4 , Alvaro Viljoen4 , Eugene Olivier4 , James Wesley-Smith5 , Thirumala Govender1
  • 1School of Pharmacy and Pharmacology, University of KwaZulu-Natal, Durban, South Africa
  • 2School of Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
  • 3Plastic Surgery Department, Centre Hospitalier Universitaire Vaudois CHUV, Lausanne, Switzerland
  • 4Department of Pharmaceutical Sciences, Tshwane University of Technology, Pretoria, South Africa
  • 5Electron Microscope Unit, University of KwaZulu-Natal, Durban, South Africa
Further Information

Publication History

received Sept. 6, 2011 revised Nov. 16, 2011

accepted Nov. 18, 2011

Publication Date:
12 December 2011 (online)

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Abstract

The buccal mucosal route offers several advantages but the delivery of certain drugs can be limited by low membrane permeability. This study investigated the buccal permeability properties of didanosine (ddI) and assessed the potential of Aloe vera gel (AVgel) as a novel buccal permeation enhancer. Permeation studies were performed using Franz diffusion cells, and the drug was quantified by UV spectroscopy. Histomorphological evaluations were undertaken using light and transmission electron microscopy. The permeability of ddI was concentration-dependent, and it did not have any adverse effects on the buccal mucosae. A linear relationship (R2 = 0.9557) between the concentrations and flux indicated passive diffusion as the mechanism of drug transport. AVgel at concentrations of 0.25 to 2 %w/v enhanced ddI permeability with enhancement ratios from 5.09 (0.25 %w/v) to 11.78 (2 %w/v) but decreased permeability at 4 and 6 %w/v. Ultrastructural analysis of the buccal mucosae treated with phosphate buffer saline pH 7.4 (PBS), ddI/PBS, and ddI/PBS/AVgel 0.5 %w/v showed cells with normal plasmalemma, well-developed cristae, and nuclei with regular nuclear envelopes. However, cells from 1, 2, and 6 %w/v AVgel-treated mucosae showed irregular nuclear outlines, increased intercellular spacing, and plasmalemma crenulations. This study demonstrates the potential of AVgel as a buccal permeation enhancer for ddI to improve anti-HIV and AIDS therapy.

Key words

buccal - didanosine - permeation enhancer - histomorphology - Aloe vera (L.) Burm. F. - Aloe barbadensis Miller - Asphodelaceae

Supporting Information

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Prof. Thirumala Govender

School of Pharmacy and Pharmacology
University of KwaZulu-Natal

Private Bag X54001, Durban

4000, KwaZulu-Natal

South Africa

Phone: +27 3 12 60 73 58

Fax: +27 3 12 60 77 92

Email: govenderth@ukzn.ac.za

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