Penetration Enhancing Effect of Polysorbate 20 and 80 on
the In Vitro Percutaneous Absorption of
L-Ascorbic Acid
N Akhtar1,
MU Rehman1, HMS Khan1, F Rasool2,
T Saeed2 and G Murtaza3*
1Faculty
of Pharmacy and Alternative Medicine, The Islamia
University of Bahawalpur, Bahawalpur 63100;
2University
College of Pharmacy, University of the Punjab, Lahore,
Pakistan;
3Department
of Pharmaceutical Sciences, COMSATS Institute of
Information Technology, Abbottabad, Pakistan
For correspondence:
E-mail:
gmdogar356@gmail.com; Fax: 0092992383441;
Tel: 00923142082826
Received: 8 August
2010 Revised
accepted: 2 April 2011
Tropical
Journal of Pharmaceutical Research, June 2011;
10(3):
281-288
doi:
10.4314/tjpr.v10i3.1
Abstract
Purpose:
To investigate the penetration enhancing effect of two
polysorbates - polyoxyethylene 20 (POE-20) and
polyoxyethylene 80 (POE-80) - on the in vitro
percutaneous absorption of ascorbic acid (AA).
Methods:
For the permeation experiments, Franz diffusion cell
covered with aluminum foil providing an effective
diffusion area of 1.76 cm2 and hairless
rabbit skin were used. A range of concentrations (1 – 5
%) of POE-20 and POE-80 was added to the ascorbic acid
to determine their optimum enhancement concentration.
Results:
The cumulative amount of AA that diffused across the
skin increased with increase in the concentration of the
permeation enhancers. Without the enhancer, AA flux was
0.626 µg/cm2/h while mean permeability
coefficient (Kp) was 2.09 × 10-6
cm/h. AA flux was 3.17 and 2.44 µg/cm2/h for
POE-20 and POE-80, respectively, while mean permeability
coefficient was 10.6 × 10-6 and 8.14 × 10-6
Kp, cm/h. Maximum flux (3.16 µg/cm2/h)
at POE-20 concentration of 5 % was obtained, with an
enhancement ratio (ER) of 5.07 in relation to control
(i.e., AA without enhancer). For POE-80 (5 %), maximum
flux was 2.44 µg/cm2/h with an ER value of
3.89, compared to control.
Conclusion:
This study
demonstrates that POE-20 and POE-80 exerted a
penetration enhancing effect on the percutaneous
absorption of L-ascorbic acid (AA).
Keywords:
L-Ascorbic
acid, Skin permeation, Polyoxyethylene (Polysorbate),
Flux, Penetration enhancers
