Simultaneous Estimation of Amoxycillin and Potassium Clavulanate in Injection Formulation By simultaneous equation method and its validation

A simple, fast and precise simultaneous equation method has been developed for simultaneous determination of Amoxycillin (AMX) and Potassium clavulanate (PTC)in injection formulation. The absorption maxima were found to be 246.6 nm for AMX and 257.6 nm for PTC in 0.1M NaOH used as the solvent. The linearity for these drugs at the selected wavelengths lies between 0-200 μg/ml for AMX and 0-75 μg/ml for PTC. The concentrations of these drugs were evaluated in laboratory mixture and marketed formulation. Accuracy was determined by recovery study from injection dosages forms were found to be 99.75 for AMX and 99.08 for PTC.Precision of method was determined as repeatability, day to day and analyst to analyst variation and a show the value within acceptable limit i.e R.S.D was found to be less than 2 percent).RESULTS AND DISCUSSIONThe UV spectra of AMX and PTC, obtained from different solvent (methanol, water, 0.1mHCl and 0.1M NaOH) were studied. The wavelength maximum of the main band was found to be dependent of solvent effects. In water lmax found to be 228nm AMX and 222nm for PTC, butthe injection powder was turbid and non filterable. Also the lmax of both drugs found to be very close. In 0.1M HCl drug is freely soluble and lmax found to be 229nm AMX and224.2nm for PTC but the drug stock solution were dark and yellowish in colour. In methanol drug is slightly soluble and ?max found to be 232nm AMX and 220.8nm for PTC, but as per solvent effect ( Bathochromic shift ) the lmax of PTC could not be considerable. In case of 0.1M NaOH the drug is freely soluble and ?max found to be 246.8nm AMX and 257.6nm for PTC. Thus at the end of these studies 0.1M NaOH was selected as best solvent because it fulfill all the parameters required for simultaneous estimation and also to avoid the time gain while preparing solution and cost saving by eliminating the purchase and disposal of organicsolvent. After considering the solubility, stability and economic feature for both the drugs, 0.1M NaOH was selected as the solvent. From the characteristic spectra of the two drugs ?max was observed at 246.8nm &amp; 257.6nm for AMX and PTC respectively. The linearity was observed in the range of 0-200 ìg per ml for AMX and 0-75 ìg per ml for PTC in the selected solvent.CONCLUSIONThe present work concerned with method development and its validation for simultaneous estimation of Amoxycillin and Pot.Clavulanate by simultaneous equation method.The methodinvolved responses were measured for a series of dilutions, in concentration range of 10-50mg/ml for Amoxycillin and 2-10mg/ml for Pot. Clavulanate at their selected wavelength. The value of relative standard deviation (R.S.D.) for the validation parameters (linearity, repeatability intermediate and precision) was found below 2 hence this method can be used in the laboratories for estimation of this combination.<br>