Formulation Development and Optimization of Ibuprofen Poloxamer Melt Granules Using Hydrophilic Excipients

The focus of this research work was to develop a melt granulation technique to enhance solubility, dissolution rate and associated flowability concerns of Ibuprofen. Hydrophilic excipients like xylitol and lactose anhydrous were added to the binary mixture of conventional low melting surfactant Poloxamer 407 and Ibuprofen. Physical mixtures of Ibuprofen and Poloxamer 407 were prepared in ratios of 1:0.25, 1:0.5 and 1:0.75 using a water-jacketed high shear mixer. For each ratio of Ibuprofen and Poloxamer 407, xylitol and lactose anhydrous were added separately at two levels (75 mg and 150 mg) per unit dose containing 200 mg drug. Phase solubility studies revealed linearity in drug solubility enhancement with Poloxamer 407 concentration. In vitro dissolution studies were carried out for drug, physical mixtures (PM) and melt granules (MG) for all ratios in de-ionized water and 0.1 N HCl (pH=1.2). Solid state characterization was performed using Fourier transform infrared spectroscopy (FTIR), modulated differential scanning calorimetry (mDSC) and powder X-ray diffraction (PXRD) methodologies. Powder rheology studies were performed conventionally by measuring Carr’s index and Hausner’s ratio. Basic flowability energy values were calculated using a powder rheometer to corroborate flowability data measured by conventional methods. Particle morphological studies were done by Scanning electron microscope (SEM) and Fluid imaging technologies. In-vitro dissolution studies showed approximately 7 fold drug release in water and 19 fold drug release in acidic media for MG 1:0.75 at hydrophilic excipient level of 150 mg compared to that of neat Ibuprofen in respective dissolution media. mDSC and PXRD data confirms crystalline nature of drug in the formulations. FTIR data confirms no interactions between drug and excipients used during processing. Particle morphology analysis confirms absence of rhombic Ibuprofen crystals in formulations. Dissolution rate and solubility enhancement was seen due to synergistic effects of Poloxamer 407 and hydrophilic excipients incorporated in formulations.