DETERMINATION OF SOME NONSTEROID ANTIINFLAMMATORY DRUGS BY CAPILLARY ISOTACHOPHORESIS

The isotachophoretic (ITP) behaviour and separation of the anti-inflam matory drugs kebuzone (KB), tribuzone (TB) and phenylbutazone (PB) was studied in the operational system of HCl/His (leading electrolyte, LE ) and 4-nitrophenol (terminating electrolyte, TE). The effective mobil ities were 19.4 x 10(-9) m(2) V-1 s(-1) for KB, 18.1 x 10(-9) m(2) V-1 s(-1) for TB and 18.9 x 10(-9) m(2) V-1 s(-1) for PB when using an op timised system with 10 mM HCl + 40 mM His (pH 6.63) as LE and 10 mM 4- nitrophenol as TE. The calibration graphs were rectilinear (r = 0.9982 -0.9996) in the range 20 to 600 mu mol l(-1) of KB, TB or PB. The ITP method was used for determining the content of KB, TB or PB in mass-pr oduced pharmaceuticals as tablets, coated tablets, injections, and oin tments. The results of the ITP determination were in good agreement wi th those of standard pharmacopoeial methods.