Asian Journal of Biomedical and Pharmaceutical Sciences

- Asian Journal of Biomedical and Pharmaceutical Sciences (2014) Volume 4, Issue 40

?Solid as Solvent?- Novel Technique for Spectrophotometric Analysis of Ornidazole Tablets Using Melted Phenol as Solvent

Commonly used organic solvents for spectrophotometric analysis of water insoluble drugs include methanol, ethanol, chloroform, benzene, dichloromethane, dimethyl formamide, acetonitrile, ethyl acetate, toluene, carbon tetrachloride, acetone, hexane etc. The main drawbacks of organic solvents include high cost, toxicity and pollution. Organic solvents have numerous adverse effects caused by single exposure like dermatitis, headache, drowsiness, nausea, eye irritation and long term exposure causes serious effects such as neurological disorders, chronic renal failure, liver damage, necrosis, mutagenesis disorder. They should be replaced by other eco-friendly alternative sources. The present investigation is an attempt to show that solids can also be wisely used to act as solvent precluding the use of organic solvents. In a separate study, author has attempted soxhelation using phenol as solvent. The vapours of boiling phenol got condensed in extraction chamber to effect the extraction of active constituents from powder of crude drugs. The main objective of the present study is to demonstrate the solvent action of solids. Solid excipients can nicely be employed as solubilizers in the development of pharmaceutical dosage forms in solution form of poorly soluble drugs (mixed solvency concept). Present study describes the application of solvent character of melted phenol (at 50-60°C) for spectrophotometric estimation of ornidazole tablets. Solubility of ornidazole in distilled water is 8.03 mg/ml. More than 700 mg of ornidazole dissolves in one gram of melted phenol (at 50-60°C). In the present investigation, melted phenol (at 50-60°C) was utilized to extract out (dissolve) the drug from powder of ornidazole tablets. Distilled water was used for dilution purpose. Absorbances of standard solutions containing 5, 10, 15, 20 and 25 μg/ml were noted at 319 nm against reagent blanks to obtain calibration curve. Proposed method is novel, economic, eco-friendly, 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 and phenol did not interfere in the spectrophotometric estimation at 319 nm. Phenol does not interfere in spectrophotometric estimation above 300 nm.

Author(s): Jain DK, Patel V, Banjare L, Jain N, Maheshwari RK

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