No abstract

Usnic acid, a compound produced by Usnea sp, has been reported for anti-oxidant activity. However, the use of usnic acid is still finite due to poor solubility in water. One of the processes to increase the solubility is by preparing into solid dispersion using hydrophilic polymer. The aims of this study were to prepare usnic acid in solid dispersion using poly-vinyl-pyrrolidone (PVP) K30 and evaluate its antioxidant activity. Solid dispersions were prepared using spray and freeze-drying method at a ratio of usnic acid:PVP of 1:1 and 1:2 (w/w). The physical mixture at the same ratio was prepared as a comparison. The morphology of solid dispersion, which was depicted in scanning electron microscopy (SEM) analysis, showed rod crystal for usnic acid; sphere particles for PVP K30 and spray dried powder; porous particles for freeze-dried powder, and usnic acid embedded on the surface of PVP K-30 for the physical mixture. The amount of usnic acid dissolved in water was determined using a UV-Vis spectrophotometer. Freeze dried usnic acid-PVP at ratio 1:2 showed the highest solubility which was about 20-fold compared to intact usnic acid. Antioxidant activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and gallic acid was used as the reference. The result of antioxidant activity test showed the inhibition concentration 50% (IC50) were 12.471, 80.242 and 63.867 µg/ml for gallic acid, intact usnic acid and freeze-dried usnic acid at ratio 1:2, respectively. In conclusion, solid dispersion is able to increase the solubility of usnic acid and the antioxidant activity is in accordance with the solubility result.

Fenofibric acid is an active form of fenofibrate which has an antihyperlipidemic effect. Fenofibric acid belongs to BCS class II, which has low solubility and high permeability. The aim of this study was to form multicomponent crystal of fenofibric acid and saccharin that can increase the solubility and dissolution rate, as well as impact on its effectiveness. The ratio of the mixture of fenofibric acid and saccharin was determined using two phase diagram. Characterizations were carried out by Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), and the evaluations carried out are solubility, dissolution rate and antihyperlipidemic effectiveness. Based on the two phase diagram a mixture of fenofibric acid and saccharin produce eutectic point at 1:1 mole ratio. Multicomponent crystal showed a decrease in melting point with DSC analysis, no new crystalline phase was formed in X-ray diffraction analysis and did not show any chemical interactions in FTIR analysis. Multicomponent crystal showed an increase in the solubility and dissolution rate. The results of the effectiveness of antihyperlipidemic showed that multicomponent crystal was more effective than fenofibric acid.

Parasetamol merupakan obat yang agak sukar larut dalam air. Absorbsi obat sukar larut atau agak sukar larut dalam air dipengaruhi oleh laju pelarutan. Solubilisasi merupakan alternatif untuk meningkatkan kelarutan obat dalam air dengan penambahan surfaktan. Penambahan surfaktan Ryoto® sugar ester dan kosolven propilen glikol dilakukan untuk menentukan konsentrasi Ryoto® sugar ester dan prolilen glikol yang dapat meningkatan kelarutan dan stabilitas sediaan. Solubilisasi parasetamol dengan penambahan Ryoto®  sugar ester tanpa propilen glikol dan kombinasi penambahan Ryoto® sugar ester dan propilen glikol pada konsentrasi dibawah titik CMC (Critical Micell Concentration), pada titik CMC, dan diatas titik CMC berturut-turut adalah 0,005 mg/ml, 0,006 mg/ml, dan 0,007 mg/ml dengan 10% propilen glikol. Kelarutan parasetamol tertinggi dicapai pada formula 7 dengan kombinasi penambahan Ryoto® sugar ester (0,007 mg/ml) dan propilen glikol (10%) yaitu dengan persentase perolehan kembali 99,6 %, serta pada kombinasi ini juga diperoleh stabilitas sediaan yang paling bagus yaitu tidak terjadinya perubahan warna pada sediaan selama penyimpanan pada suhu kamar dan ditempat yang terlindung dari cahaya matahari langsung selama satu bulan. Penambahan surfaktan Ryoto® sugar ester dan propilen glikol dapat meningkatkan kelarutan dan stabilitas sediaan solubilisasi parasetamol.

Fenofibric Acid (FA) is classified under Biopharmaceutical Classification System (BCS) class II due to its poorly soluble in water and high permeability. The present study aimed to prepare the eutectic mixture of FA with nicotinic acid (NA) and characterize its solid state properties and in vitro dissolution rate, along with its in vivo antihyperlipidemic activity. Solvent drop grinding was the method chosen to prepare the eutectic mixture of FA and NA. Solid-state properties were evaluated using thermal analysis Differential Scanning Calorimetry (DSC), crystallographic analysis Powder X-Ray Diffraction (PXRD), FT-IR spectroscopic analysis, and Scanning Electron Microscopy (SEM). To examine in vivo antihyperlipidemic activity, 16 male Swiss Webster rats were injected with 1% hyperlipidemia-inducing solution, followed by the oral administration of 9.45 mg/kg FA and NA (equivalent to 9.45 mg/kg FA), after which the decrease in cholesterol levels was measured. Two-way ANOVA was used to evaluate the data, followed by Duncan’s multiple range test (95% confidence interval). The results proved that FA formed the eutectic mixture with NA at a molar ratio of 6:4. The eutectic mixture of FA-NA had a better solubility and in vitro dissolution rate compared to intact FA, which also led to notably improved antihyperlipidemic activity.