Improvement of Dissolution Characteristics of Meloxicam by Complexation with Cyclodextrins

Abstract

The aim of the present study was an attempt to prepare tablets containing inclusion complexes of meloxicam with β-cyclodextrins and hydroxypropyl-β-cyclodextrin to improve the aqueous solubility of the drug, thus enhances its dissolution rate to show a faster onset of action.  Complexation with cyclodextrins has been used as novel approach for designing drug delivery system because of ability for the non-covalent inclusion complexes formation and it has the ability to molecular encapsulate meloxicam into their hydrophobic cavity without the formation of any covalent bonds. Meloxicam complexation with cyclodextrin enhance the drug solubility and dissolution rate. Also cyclodextrins enhance the bioavailability of insoluble drugs by increasing the drug solubility, dissolution and permeability. The carriers used in this study are β-cyclodextrin and hydroxypropyl-β-cyclodextrin. Solid complexes of meloxicam with β-cyclodextrin and hydroxypropyl-β-cyclodextrin were prepared by two different methods namely, Kneading and Co-evaporation techniques. For kneading method, water-methanol-dichloromethane at 2 : 5 : 3 ratio was used as a solvent blend and for co-evaporation techniques, methanol-dichloromethane was used as solvent blend at 2 : 3 ratio. In each case different proportions of drug and carriers at 90 : 10, 75 : 25, 50 : 50, 25 : 75, 10 : 90 were used in the preparation of solid complexes to evaluate the effect of carrier concentrations on the dissolution characteristics.  A total of 20 meloxicam solid complexes with different carriers were prepared, found to be fine and free flowing powders. The estimated drug content  of the prepared complexes were in the range of 100  ± 5%. The dissolution parameters of T50 and dissolution rate indicated rapid dissolution of meloxicam from the solid complexes when compared with the pure drug and physical mixture. Meloxicam-β-CD (10 : 90) complex gave the highest dissolution rate.