New spectrophotometric estimation of ornidazole tablets employing urea as a hydrotropic solubilizing additive

Quantitative spectrophotometric analysis of poorly water-soluble drugs involves use of various organic solvents. Major drawbacks of organic solvents include high cost, volatility and toxicity. Safety of analyzer is affected by toxicity of the solvent used. In the present investigation the use of organic solvent has been avoided, making the method environmentally friendly. Urea has demonstrated enhancement in aqueous solubilities of a large number of poorly water-soluble drugs, thereby widely used as a hydrotropic agent. There was more than 10-fold enhancement in the solubility of ornidazole in 10 M urea solution as compared to its solubility in distilled water. In the present investigation, hydrotropic solution of urea (10 M) was employed as solubilizing agent to solubilize the poorly water-soluble drug, ornidazole, from fine powder of its tablet dosage form for spectrophotometric determination in ultraviolet region at 319 nm. Beer's law was obeyed in the concentration range of 5-25 μg/ml in presence of urea. Presence of urea did not interfere in the analysis. Proposed method is new, rapid, simple, accurate, and reproducible. Statistical data proved the accuracy, reproducibility and the precision of the proposed method.