The Effect of Surfactant Type and Concentration on Physicochemical Properties of Carvedilol Solid Dispersions Prepared by Wet Milling Method

The present study mainly aimed to prepare solid dispersions (SDs) of a poorly water-soluble compound, carvedilol (CA), in the presence of pluronic F68 (F68) and myrj 52 by wet milling technique in order to enhance drug dissolution. The process enabled the preparation of SDs without using any toxic organic solvents. SDs with different CA: surfactant ratios were prepared by wet milling followed by freeze-drying method and evaluated for their particle size and dissolution. They were also characterized based on/using X-ray diffraction (XRD), differential scanning calorimetry (DSC), fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), and saturated solubility. The effect of cryoprotectant type on the dissolution and particle size of SDs was also investigated. Wet milling process resulted in the reduced particle size depending on the type of surfactant. The significant drug dissolution and saturated solubility enhancement were recorded for milled SD formulations. In this regard, Myrj had a greater impact compared to F68. Dissolution efficiencies (DE(30)) obtained for the myrj-included SDs were up to 8.2-fold higher than that of untreated CA. The type of cryoprotectant was also found to affect the drug dissolution. According to the results, partial amorphization occurred in wet-milled samples, as confirmed by XRD and DSC analysis. It was concluded that using an appropriate surfactant along with wet-milling method may have been an effective approach for improving the dissolution rate of CA, a poorly soluble compound.