MOCLOBEMIDE-SELECTIVE MEMBRANE-ELECTRODE AND ITS PHARMACEUTICAL APPLICATIONS

A liquid membrane electrode prepared with moclobemide-dipicrylamine io n-pair complex, dissolved in nitrobenzene as solvent, was studied for analytical performance. The linear response covers the range 10(-3)-10 (-6) M moclobemide solution, with a slope of 50.7 mV decade(-1) (pH ra nge 3.5-8), The detection limit is 3 x 10(-7) M. The electrode shows s tability, good reproducibility and fast response. The selectivity of t he electrode is good, There are two important interfering ions: mianse rin and thiamine (Vitamin B-1). The compression excipients (such as Mg 2+, starch, talcum powder) do not interfere. These characteristics of the electrode enabled it to be used for the determination of moclobemi de in drugs and as an active substance, via indirect and direct potent iometric methods. Via an indirect potentiometric method moclobemide, a s an active substance, can be determined with an average recovery of 9 9.96% and a relative standard deviation of 0.85%, and this method can also be used for its determination in drugs with a relative standard d eviation of <2%. The electrode is useful for the determination of the dissolution rate of moclobemide tablets, The physical processes are nu merically simulated by typical equations. The apparent first-order rat e constants for disintegration and dissolution were calculated.