Ion Selective Membrane Electrodes for the Determination of Mixture of Analgin and Camylofin Dihydrochloride in their Pure Form and Combined Dosage Form

In the present work two selective and sensitive polyvinyl chloride matrix membrane electrodes were developed for the determination of analgin and camylofin dihydrochloride. Sensor I was developed using tetraheptylammonium bromide as an anion exchanger with 2-nitrophenyl octyl ether as a plasticizer for the determination of the anionic drug analgin. Sensor II was developed using potassium tetrakis 4-chlorophenyl borate as a cationic exchanger and dioctyl phthalate as a plasticizer for the determination of the cationic drug camylofin. Selective molecular recognition component 4-tert-butylcalix [8]arene was used as ionophore to improve the selectivity of sensor II. The linearity range of the proposed sensors was (1.56×10-4-1.00×10-2) and (1.00×10-6-1.00×10-2) mol L-1 with Nernstian slopes of (-53.45±2.93) and (30.20±1.66) for the sensors I and II, respectively. The Nernstian slopes were also estimated over the pH ranges of 4.5-10.5 and 4.5-7.5 for both sensors. The proposed sensors showed useful analytical features for the determination of both drugs in bulk powder, in laboratory prepared mixtures and in their combined solid dosage form. The method was validated according to ICH guidelines.