Abstract

“SOLID AS SOLVENT”- NOVEL SPECTROPHOTOMETRIC ANALYTICAL TECHNIQUE FOR QUANTITATIVE ESTIMATION OF PIROXICAM IN TABLETS USING SOLIDS (EUTECTIC LIQUID OF PHENOL AND LIGNOCAINE HYDROCHLORIDE) AS SOLUBILIZING AGENTS (MIXED SOLVENCY CONCEPT)

*Ashish Singh and R. K. Maheshwari

Abstract

The present attempt of research is to provide an alternate method based on mixed solvency concept to estimate a poorly water-soluble drug, piroxicam in tablet formulations without the help of organic solvent spectrophotometrically. The main objective of the present study is to demonstrate the solvent action of solids. A eutectic liquid (PL 41) obtained by triturating phenol crystals and lignocaine hydrochloride in 4:1 ratio on weight basis was employed to extract (dissolve) piroxicam drug from fine powder of its tablets. Distilled water was used for dilution to carry out spectrophotometric estimation at 358 nm. The solubility of piroxicam in distilled water at room temperature was found to be 0.401 mg/ml. The solubility of the same drug in PL 41 was more than 145 mg/ml. Proposed spectrophotometric analytical method is novel, economic, rapid, free from toxicity of organic solvent, accurate and reproducible. Recovery studies and statistical data proved the accuracy, reproducibility and precision of the proposed method. The presence of tablet excipients, phenol and lignocaine hydrochloride did not interfere in the spectrophotometric estimation at 358 nm. Phenol does not interfere above 300 nm while lignocaine hydrochloride does not interfere above 310nm.

Keywords: Mixed-solvency concept, piroxicam, phenol, lignocaine hydrochloride, spectrophotometric analysis, eutectic liquid.