STEP TOWORDS THE FORMULATION OF INJECTABLE HYDROGEL: PREFORMULATION STUDIES OF TERIFLUNOMIDE

Purpose: The aim of formulation of this hydrogel is to treat the osteoarthritis which is one of the common inflammatory autoimmune disorders of joints. The use of conventional drugs like NSAIDs having various side effects. 
The aim of our research was to develop a formulation of injectable hydrogel containing teriflunomide. This study will be helps us for the development of stable, robust and therapeutically effective dosage form. 
Method: Solubility of Teriflunomaide was determined by using various solvents. By using infrared spectrum and  absorption maxima the purity of sample was checked. With the help of UV spectrophotometer standard UV curve was developed. Drug excipients compatibility studies were performed using Fourier transform infrared spectroscopy, differential scanning colorimetry, partition coefficient and also short term drug solution stability studies were performed. 
Result: Teriflunomide is soluble in methanol & 0.1 N NaOH on the other hand poorly soluble in distilled water, phosphate buffer (pH 7.4) and 0.1 N HCl. Absorption maxima was observed at 292nm and infrared spectrum was showing the characteristic peaks.  The standard curve obtained was linear with correlation coefficient below 1. Log P value obtained at 2.78 it confirms that teriflunomide is having both hydrophilic & hydrophobic nature.  After the entire short term stability studies drug was found to be stable in short term stability studies. 
Conclusion: The studies like melting point, FTIR etc suggested that drug selected for the formulation was found to be pure. Partition coefficient values suggested that it is having both hydrophilic and hydrophobic nature. Results obtained from short term stability studies were suggested that drug is stable showing no degradation on phosphate buffer which confirmed by no shift of  λ max.