Dissolution Behavior Of Solid Dispersions Research Articles

UV-Vis Spectroscopy to Enable Determination of the Dissolution Behavior of Solid Dispersions Containing Curcumin and Piperine

Objective: Curcumin and piperine exibit poor aqueous solubility and dissolution. Solid dispersion technology is a promising way to improve dissolution of lipophilic compounds. Therefore, to investigate the dissolution behavior, an accurate determination of curcumin and piperine concentrations in a sample containing 0.5 wt-% SLS in sodium phosphate buffer as the dissolution medium was required. The goal of research was to investigate whether UV-Vis spectroscopy can be used to accurately determine curcumin and piperine concentrations in aqueous solutions. Method: Stock solutions (1 mg/mL) of curcumin and piperine were prepared in methanol. A series of solutions for calibration were prepared by mixing the stock solutions in various ratios after which they were diluted with dissolution medium (0.5%-wt sodium lauryl sulfate in 20 mM phosphate buffer; pH 6.0). Solutions of curcumin (2μg/mL) and piperine (1 μg/mL were subjected to overlay scan in a UV-VIS spectrophotometer in each λmax of 430 and 335.5 nm for curcumin and piperine, respectively. The method was validated according ICH requirements, such as specificity, linearity, accuracy, precision, limit of detection and limit of quantification. Results: At a concentration range of 0.1 to 5μg/mL, calibration curves of curcumin and piperine showed linearity with R2 = 0.9980 and 0.9982, respectively. Precision and accuracy was confirmed by AOAC. Furthermore, LOD of both compounds was 0.23 μg/mL and LOQ of curcumin and piperine was 0.72 and 0.69μg/mL, respectively. Conclusion: UV-Vis spectroscopy can be used to accurately determine curcumin and piperine concentrations in dissolution samples obtained during screening the dissolution behavior of solid dispersions containing these compounds. Key words: Curcumin, Piperine, Dissolution, UV-Vis spectroscopy.

Enhanced dissolution rate of celecoxib using PVP and/or HPMC-based solid dispersions prepared by spray drying method

Celecoxib with low solubility and high permeability (BCS class II) in water is a non-steroidal anti-inflammatory drug used in the treatment of pain and inflammation, associated with rheumatoid arthritis, and several other inflammatory disorders. Also, it is a selective cyclooxygenase 2 inhibitor with low water solubility and high crystallinity. The objective of this study was to improve dissolution rate of celecoxib which was water-insoluble drug. Solid dispersions were prepared by spray drying as the solvent evaporation method. The dissolution behavior of solid dispersions was compared with Celebrex® (Pfizer) as a control group in simulated gastric juice (pH 1.2, 0.5 % SLS. The characterization of the prepared solid dispersions is analyzed by scanning electron microscope, powder X-ray diffractometer, Fourier transform infrared spectroscopy and reverse phase-high performance liquid chromatography The best formulation was SD 8 in this study. It was the cumulative release of 97 % at 120 min. This study suggests that the solubility and bioavailability of poorly water-soluble celecoxib improved through the prepared solid dispersions by spray drying method.

Preparation, characterization and in vitro dissolution of aceclofenac-loaded PVP solid dispersions prepared by spray drying or rotary evaporation method

This study was conducted to enhance dissolution rate of aceclofenac (ACF) with extremely low solubility and high permeability (BCS class II) in water using poly vinyl pyrrolidone (PVP) and sodium lauryl sulfate as carriers. Solid dispersions were prepared by spray drying method and rotary evaporation method using different ratios of ACF and polymers. The characterization of solid dispersions was evaluated by scanning electron microscopy, Fourier transformation infrared spectroscopy, differential scanning calorimetry and powder X-ray diffractometer. The dissolution behavior of solid dispersions was compared with pure ACF (API) and Airtal® (Deawoong, Co, Korea) as control groups in simulated phosphate buffer at pH 6.8. The dissolution rate of the drug was affected by nature and amount of polymer used. The prepared solid dispersion of ACF/PVP (1:5) appeared to have the highest dissolution rate. Therefore, solid dispersion techniques of spray drying and rotary evaporation method can be successfully used for the enhancement of the dissolution rate of ACF.