[FI-ICL determination of isoniazide]

A novel flow injection inhibitory chemiluminescence (FI-ICL) system for the determination of isoniazide is presented. While isoniazide mixed with hexacyanoferrate stream, by the fast oxidation reaction between isoniazide and K3Fe(CN)6, K4Fe(CN)6 was generated, which then inhibit the CL reaction of K3Fe(CN)6 and luminol. The CL emission was correlated with the isoniazide concentration in the range from 1.40 x 10(-3) to 5.50 micrograms.mL-1, the D.L. is 4.8 x 10(-4) micrograms.mL-1 (3 sigma); and the RSD is less than 3.5% for 5.5 x 10(-2) micrograms.mL-1 isoniazide (n = 9). This system has been applied for the determination of isoniazide in pharmaceutical samples and the recovery is from 98.2% to 101%.