Design and Evaluation of Phyto-Phospholipid Complexes (Phytosomes) of Rutin for Transdermal Application

The polyphenolic flavonoid Rutin possesses multiple therapeutic effects out of which the anti-inflammatory potential has been well established in the recent literatures. The oral bioavailability of Rutin is very low necessitating its novel drug delivery approach. Phyto-phospholipid complex (phytosomes) is helpful in enhancing oral bioavailability and transdermal permeation of polyphenols. In the present work, Rutin phytosomes (RN-P) were developed and characterized to establish its feasibility for transdermal application in inflammatory conditions. Phytosomes were prepared in five molar ratios of Rutin (0.5 - 1.0) to Phosphatidylcholine (1.0 - 0.5). All RN-Ps showed aqueous solubility higher than pure Rutin. Partition coefficient results indicated the lipophilic nature of free Rutin as well as all RN-Ps with most satisfactory value found at 3.11 ± 0.08 with F3 formulation. Discrete vesicular structures of RN-Ps observed in TEM study. Results of the FT-IR, DSC and XRD studies confirmed the phyto-phospholipid complex formation. XRD reports revealed the reduction in crystallinity of Rutin when in phytosomes form with F3 found to be the least crystalline. SEM studies confirmed the disappearance of rod shaped crystals of Rutin in phytosome formulations. The ex vivo skin permeation study across excised rat abdominal skin confirmed the higher permeability of RN-Ps (33 ± 1.33 %) over pure Rutin (13 ± 0.87 %). The observations made in the present work suggest that phyto-phospholipid complex of Rutin can increase its skin uptake to treat inflammatory conditions in arthritis, rheumatism, athletic aches and may able to deliver the drug for a long duration avoiding the problems associated with oral administration.