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DOI: 10.1055/s-0031-1280431
© Georg Thieme Verlag KG Stuttgart · New York
Investigating the Effect of Aloe vera Gel on the Buccal Permeability of Didanosine
Publication History
received Sept. 6, 2011
revised Nov. 16, 2011
accepted Nov. 18, 2011
Publication Date:
12 December 2011 (online)

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
References
- 1
Rathbun R C, Lockhart S M, Stephens J R.
Current HIV treatment guidelines – an overview.
Curr Pharm Des.
2006;
12
1045-1063
MissingFormLabel
- 2
Heyer A, Ogunbanjo G A.
Adherence to HIV antiretroviral therapy Part II: which interventions are effective
in improving adherence?.
SA Fam Pract.
2006;
48
6-10
MissingFormLabel
- 3
Xiang J, Fang X, Li X.
Transbuccal delivery of 2′,3′-dideoxycytidine: in vitro permeation study and histological investigation.
Int J Pharm.
2002;
231
57-66
MissingFormLabel
- 4
Li X, Chan W K.
Transport, metabolism and elimination mechanisms of anti-HIV agents.
Adv Drug Deliv Rev.
1999;
39
81-103
MissingFormLabel
- 5
Pather S I, Rathbone M J, Senel S.
Current status and the future of buccal drug delivery systems.
Expert Opin Drug Deliv.
2008;
5
531-542
MissingFormLabel
- 6
Rossi S, Sandri G, Caramella C M.
Buccal drug delivery: A challenge already won?.
Drug Discov Today Technol.
2005;
2
59-65
MissingFormLabel
- 7
Salamat-Miller N, Chittchang M, Johnston T P.
The use of mucoadhesive polymers in buccal drug delivery.
Adv Drug Deliv Rev.
2005;
57
1666-1691
MissingFormLabel
- 8
Narishetty S T K, Panchagnula R.
Effect of L-menthol and 1,8-cineole on phase behaviour and molecular organization
of SC lipids and skin permeation of zidovudine.
J Control Release.
2005;
102
59-70
MissingFormLabel
- 9
Mukherji E, Millenbaugh N J, Au J L.
Percutaneous absorption of 2′,3′-dideoxyinosine in rats.
Pharm Res.
1994;
11
809-815
MissingFormLabel
- 10
Giannola L I, De Caro V, Giandalia G, Siragusa M G, Tripodo C, Florena A M, Campisi G.
Release of naltrexone on buccal mucosa: permeation studies, histological aspects and
matrix system design.
Eur J Pharm Biopharm.
2007;
67
425-433
MissingFormLabel
- 11
Senel S, Hincal A A.
Drug permeation enhancement via buccal route: possibilities and limitations.
J Control Release.
2001;
72
133-144
MissingFormLabel
- 12
Femenia A, Sánchez E S, Simal S, Rosselló C.
Compositional features of polysaccharides from Aloe vera (Aloe barbadensis Miller) plant tissues.
Carbohydr Polym.
1999;
39
109-117
MissingFormLabel
- 13
Chen W, Lu Z, Viljoen A, Hamman J.
Intestinal drug transport enhancement by Aloe vera.
Planta Med.
2009;
75
587-595
MissingFormLabel
- 14
Reynolds T, Dweck A C.
Aloe vera leaf gel: a review update.
J Ethnopharmacol.
1999;
68
3-37
MissingFormLabel
- 15
Boudreau M D, Beland F A.
An evaluation of the biological and toxicological properties of Aloe barbadensis (Miller), Aloe vera.
J Environ Sci Health C.
2006;
24
103-154
MissingFormLabel
- 16
Pugh N, Ross S A, ElSohly M A, Pasco D S.
Characterization of aloeride, a new high-molecular-weight polysaccharide from Aloe vera with potent immunostimulatory activity.
J Agric Food Chem.
2001;
49
1030-1034
MissingFormLabel
- 17
Cole L, Heard C.
Skin permeation enhancement potential of Aloe vera and a proposed mechanism of action based upon size exclusion and pull effect.
Int J Pharm.
2007;
333
10-16
MissingFormLabel
- 18
Jani G K, Shah D P, Jain V C, Patel M J, Vithalan D A.
Evaluating mucilage from Aloe barbadensis Miller as a pharmaceutical excipient for sustained-release matrix tablets.
Pharm Technol.
2007;
31
90-98
MissingFormLabel
- 19
Giannola L I, De Caro V, Giandalia G, Siragusa M G, Campisi G, Florena A M, Ciach T.
Diffusion of naltrexone across reconstituted human oral epithelium and histomorphological
features.
Eur J Pharm Biopharm.
2007;
65
238-246
MissingFormLabel
- 20
Koland M, Sandeep V P, Charyulu N R.
Fast dissolving sublingual films of ondansetron hydrochloride: effect of additives
on in vitro drug release and mucosal permeation.
J Young Pharm.
2010;
2
216-222
MissingFormLabel
- 21
Shojaei A H, Khan M, Lim G, Khosravan R.
Transbuccal permeation of a nucleoside analog, dideoxycytidine: effects of menthol
as a permeation enhancer.
Int J Pharm.
1999;
192
139-146
MissingFormLabel
- 22
Karnovsky M J.
A formaldehyde-glutaraldehyde fixative of high osmolality for use in electron microscopy.
J Cell Biol.
1965;
27
137A-138A
MissingFormLabel
- 23
Mahalingam R, Ravivarapu H, Redhkar S, Li X, Jasti B R.
Transbuccal delivery of 5-aza-2-deoxycytidine: effects of drug concentration, buffer
solution, and bile salts on permeation.
AAPS PharmSciTech.
2007;
8
(55)
E1-E6
MissingFormLabel
- 24
Heemstra L B, Finnin B C, Nicolazzo J A.
Buccal mucosa as an alternative route for the systemic delivery of risperidone.
J Pharm Sci.
2010;
99
4584-4592
MissingFormLabel
- 25
Hassan N, Ahad A, Ali M, Ali J.
Chemical permeation enhancers for transbuccal drug delivery.
Expert Opin Drug Deliv.
2010;
7
97-112
MissingFormLabel
- 26
Sandri G, Poggi P, Bonferoni M C, Rossi S, Ferrari F, Caramella C.
Histological evaluation of buccal penetration enhancement properties of chitosan and
trimethyl chitosan.
J Pharm Pharmacol.
2006;
58
1327-1336
MissingFormLabel
- 27
Hu L, Damaj B B, Martin R, Michniak-Kohn B B.
Enhanced in vitro transbuccal drug delivery of ondansetron HCl.
Int J Pharm.
2011;
404
66-74
MissingFormLabel
- 28
Sandri G, Rossi S, Bonferoni M C, Ferrari F, Zambito Y, Di Colo G.
Buccal penetration enhancement properties of N-trimethyl chitosan: Influence of quaternization
degree on absorption of a high molecular weight molecule.
Int J Pharm.
2005;
297
146-155
MissingFormLabel
- 29
Shin S, Cho C, Oh I.
Enhanced efficacy by percutaneous absorption of piroxicam from the ploxamer gel in
rats.
Int J Pharm.
2000;
193
213-218
MissingFormLabel
- 30
Shin S, Kim J.
Enhanced permeation of triamcinolone acetonide through the buccal mucosa.
Eur J Pharm Biopharm.
2000;
50
217-220
MissingFormLabel
- 31
Figueiras A, Hombach J, Veiga F, Bernkop-Schnürch A.
In vitro evaluation of natural and methylated cyclodextrins as buccal permeation enhancing
system for omeprazole delivery.
Eur J Pharm Biopharm.
2009;
71
339-345
MissingFormLabel
- 32
de Vries M E, Boddé H E, Verhoef J C, Ponee M, Craane W I H M, Junginger H E.
Localization of the permeability barrier inside porcine buccal mucosa: a combined
in vitro study of drug permeability, electrical resistance and tissue morphology.
Int J Pharm.
1991;
76
25-35
MissingFormLabel
- 33
Madhav N V S, Shakya A K, Shakya P, Singh K.
Orotransmucosal drug delivery systems: a review.
J Control Release.
2009;
140
2-11
MissingFormLabel
- 34
Dorr W, Jacubek A, Kummermehr J, Herrmann T, Dolling-Jochem I, Eckelt U.
Effects of stimulated repopulation on oral mucositis during conventional radiotherapy.
Radiother Oncol.
1995;
37
100-107
MissingFormLabel
Prof. Thirumala Govender
School of Pharmacy and Pharmacology
University of KwaZulu-Natal
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