Spectrophotometric Determination of sulphadiazine by oxidative coupling reaction with ortho-amino phenol as reagent


A simple, rapid and sensitive spectrophotometric method for determination of sulphadiazine (SDZ) in aqueous solution is described. The method iis based on the oxidation of SDZ by potasium Periodate, and coupling with ortho-amino phenol to give a violet colour of maximum absorbaance at 532 nm. Beer's law is obeyed over the concentration range of 5-40 µg /ml of SDZ with a (R2=0.9980) and molar absorptivity 5581.6 L.mol-1.cm-1 and a relative error in the range of - 0.06 - 2.3 % and a relative standard deviation of not more than 0.31 %. The composition of the resulting product is also investigated and it is found to be1:1. The method is successfully applied for the determinatiion of SDZ in pure and pharmaceutical dosage forms, with recovery of noot less than 101.1%.