Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID). A efficient, simple and least time consuming spectrophotometric method for the assay of diclofenac sodium has been developed. Comparison of assay of four different brands of diclofenac sodium (Dicloran, Defnac, Artifin, voltral) has also been done available in public medical store of Karachi, Pakistan. The assay is based on the ultraviolet UV absorbance maxima at about 276nm wavelength of diclofenac sodium using water as solvent. A sample of drug was dissolved in water to produce a solution containing diclofenac sodium. Similarly, a sample of ground tablets of different brand were dissolved in water and various dilutions were made. The absorbance of sample preparation was measured at 276nm against the solvent blank and the assay was determined by comparing with the absorbance of available brand. The method can be applied for the routine QC quantitation of diclofenac sodium in tablet formulation and active. Our results reveals that among all the four brands of diclofenac sodium (Dicloran, Defnac, Artifin, voltral) Defnac and voltral shows highest percentage assay 104% and Dicloran shows lowest value for percentage assay 96.4% , while artifin shows a percentage assay of 98.6%.
Keywords: Diclofenac; percentage assay; UV spectrophotometer; ANOVA
Diclofenac belong to the family of non-steroidal anti-inflammatory drugs (NSAID) or cyclo-oxygenase (COX) inhibitors. It is an effective antiinflammatory, analgesic and antipyretic agent. It is commonly used in the treatment of acute and chronic pain, rheumatoid and osteoarthritis. It acts by inhibiting COX activity and consequently the formation of pro-inflammatory © mediators such as prostaglandins (PGs) and thromboxanes[1]. The mode of analgesic action of diclofenac sodium is through inhibition (COX-2) causing a reduction in the conversion of arachidonic acid into inflammatory prostaglandins[2].
Chemically it is 2-(2,6- dichlorophenyl) amino benzeneacetic acid 4-(3H- 1,2,dithiol-3-thione-5-yl)phenyl ester [3] and is a low-molecular-weight drug (MWt:
318.13)[4]. Diclofenac sodium was found to be the most commonly used off-label medicines in UK paediatric surgical wards [5,6] and exhibit anticancer effects [7] .Our research group has developed different assay methods which are very useful for
UV visible 1601 Shimadzu double beam spectrophotometer was used to measure of spectra. The solvent which was used for the assay was water.
About 100 ppm of diclofenac sodium solution was accurately prepared in water. This solutions was scanned in the 200-400 nm UV region. The wavelength maxima (λmax) was observed at 340 nm and this wavelength was adopted for absorbance measurement.
Accurately weighed 10 mg of diclofenac sodium standard was transferred to a volumetric flask and added sufficient water to produce 100 ml.
The four different brands (dicloran, defnac, artifin, voltral) were purchased from different medical store in Karachi. All the tablets of each brand had same batch number and were labeled to contain diclofenac sodium 50mg per tablet. All the three brands have 5 year shelf life.
The serial number as an identification of purchased brands are given in Tabel 1. Twenty tablets of four different brand of diclofenac sodium from the marketed sample were weighed and crushed uniformly with the help of a mortar and pestle. By calculating the average weighed sample powder equivalent to 10 mg of diclofenac sodium was transferred into a volumetric flask containing 10mL water. The solutions were sonicated for about 5 min and then 100 ml water was added.
After preparation of standard and tablet solutions, strength of solution 100 ppm in 100 ml absorbance of the sample preparation and standard preparation in 1cm cell at the wavelength of maximum absorbance at about 340 nm, using a spectrophotometer, using the blank solution. Calculate the quantity in mg, of diclofenac sodium per tablet.
Pharmaceutical assay was carried out using spectrophotometer on all brands of diclofenac sodium tablets during the study. Table-1 shows name brand and % assay of different brands. Our results reveal that among all the four brands of diclofenac sodium (Dicloran, Defnac, Artifin, voltral) Defnac and voltral shows highest percentage assay 104% and Dicloran shows lowest value for percentage assay 96.4%, while artifin shows a percentage assay of 98.6%. Results also analysed by using SPSS software and the test used for analysis is ANOVA.
Test of hypothesis i-e ANOVA and multiple comparison of brands of diclofenac sodium
Brand Serial Average wt of Wt Name No. tablet mg ppm Dicloran Dic-1 566 Defnac Def-2 558 Artifin Art-3 372 Voltral Vol-4 448 tablet formulation is very simple, accurate, least time consuming and rapid. It can be easily used for routine quality control QC for monitoring the assay in the API, infor 100 Absorbance at % 340nm assay 283 2.137 96.24 279 2.392 104 186 2.268 98.6 224 2.398 104
The proposed method is simple, precise, accurate, and selective for the estimation of diclofenac sodium in bulk and in tablet dosage forms. The method is economical, rapid and do not require any sophisticated instruments. Hence it can be effectively used for the routine analysis of diclofenac sodium in bulk and in tablet dosage forms.