^{2nd Middle East Pharmacy and Pharmaceutical Conference}

Introduction: Nowadays, a significant number of drugs getting approvals have poor biopharmaceutical properties. One example is meloxicam (ME), a highly potent nonsteroidal anti-inflammatory drug. New drug delivery strategies have

been developed in order to overcome this issue and nanotechnology represents one of the most popular strategies. Among nanotechnology, polymeric micelles are emerging as a new Nanoplatform in several therapeutic applications such as increasing water solubility, permeability and consequently, the oral bioavailability of the drugs.The aim of this work was to demonstrate the advantages of using mixed polymeric micelles (Pluronic® F68 and P123) to encapsulate ME, when compared with the drug alone, and to characterize the prepared micelles. Morphology was studied by transmission electron microscopy. 5 μL of freshly prepared micellar dispersions were placed on Formvar and allowed to dry for 5 min. To unveil the usefulness of such formulations concerning physical stability, formulations FM1-FM5 and ME were dissolved in enteric and gastric medium. After 1 and 2 h it was quantified ME in gastric medium and after 3 and 4 h it was quantified ME in enteric medium. Quantification was performed using an UV spectrophotometer and absorbance taken at 363 nm. To determine encapsulation efficiency, FM1-FM5 were quantified immediately after preparation. Later on, micellar suspensions were centrifuged at 3000 g for 15 min using Amicon® Ultra 4 Centrifugal filter units, the supernatant was quantified and EE calculated based on the following equation:EE(%)=(conc in micelles-conc in supernatant)/(conc in micelles) x100. Finally, cytotoxicity of formulations was assessed in Caco-2 cells by Alamar Blue assay, performing a screening of crescent concentrations for each formulation. Micelles were found to present small sizes andspherical shape, with ME forming a circular line near to the micelle´s surface. All formulations significantly increased ME physical stability in enteric medium. In gastric medium, despite of FM2 and FM3 showed the best results, all the other formulations showed a significant increase on stability. With the exception of FM1, all formulations demonstrate high EE % (FM1:35.544±3.919, FM2: 93.162±1.071, FM3: 90.663±1.805, FM4: 89.840±1.991, FM5: 86.607±2.134). Finally, FM3 revealed no cytotoxicity in concentrations ranging from 0.625 to 5% and FM2 revealed no cytotoxicity in concentrations ranging from 0.625 to 2.5%. FM2 and FM3 seem to be promising formulations to efficiently encapsulate drugs with low water solubility, as meloxicam.