Effects of Dimethylformamide and L-Menthol Permeation Enhancers on Transdermal Delivery of Quercetin

Abstract

In this work a feasibility study of transdermal delivery system for quercertin (Q) in carbopol gel through abdominal hairless pig skin in vitro was performed. Dimethylformamide (DMF) and L-menthol (M) were selected as enhancers. Permeation experiences were carried out by using Franz-type diffusion cells. Phosphate saline buffer (pH 7.4) was used in the receptor compartments. All the system was maintained at 32 +/- 0.5 degrees C with a circulating water jacket and magnetic stirring (180 rpm). Samples were analysed by UV-VIS spectrophotometer at 255 nm. Flux (Jm) values, permeation (P) and diffusion (D) coefficients were obtained. Results of Q in CG permeation experiences with different percentages of DMF and M showed that 16.7% DMF and 1.95% L-menthol enhancers were the best quantities for the system tested. Enhancer effect can be attributed to direct action on membrane structure by promoting its distension. Therefore, enhancer substitutes for water in pores, improving active principal permeation through pig skin. M significantly increases Q permeation about 17 times higher than control. The results of permeation experiments with M and DMF using the same enhancer concentration (1.42%) conclude that M action is 9 times higher than DMF, approximately, indicating that M is an effective enhancer for a transdermal therapeutic system of Q in CG as vehicle.

Analytical Procedures for Determination of Quercetin and its Glycosides in Plant Material

“…In plant food, quercetin exists in a multiplicity of complex conjugates, mainly glycosides. Important questions remain on the fate of such conjugates during processing and digestion, on the nature of the nutritionally important form of quercetin and on the extent of their uptake and metabolism in the gut (4,9,110). An important prerequisite for tacking such problems is the development of convenient and reliable analytical procedures with a high-resolution separation system and appropriate quantification.…”

Comparative Evaluation of the Effect of Permeation Enhancers, Lipid Nanoparticles and Colloidal Silica on in vivo Human Skin Penetration of Quercetin

“…However, the enhancement effect achieved by these systems on quercetin uptake of the skin has been demonstrated solely in animals [16,22,23,24,25,26,27,40] or using excised human skin [20,21]; in vivo studies in humans are lacking. This is a disadvantage since in vivo studies in humans provide the most direct, realistic and therefore conclusive information on skin penetration.…”

“…Several strategies have been proposed to improve the percutaneous penetration of this flavonoid [16,20,21,22,23,24,25,26,27]. However, the enhancement effect achieved by these systems on quercetin uptake of the skin has been demonstrated solely in animals [16,22,23,24,25,26,27,40] or using excised human skin [20,21]; in vivo studies in humans are lacking.…”

“…The effect of these systems on the cutaneous delivery of quercetin has been evaluated in vitro on excised animal and human skin [16,20,21,22,23,25,26,27] and in vivo in mice [16,24]. However, no investigation under real applicative conditions of dermatological products in humans has been performed yet, which is a major drawback.…”

“…Approaches aiming to enhance the permeation of quercetin through the skin include the preparation of prodrugs of the flavonoid [21], incorporation in microemulsions [16,22,23,25], addition of penetration enhancers [20,26,27] and encapsulation in polymeric nanoparticles [24]. …”