Chemiluminescence sensor for isoniazid with controlled-reagent-release technology

A novel chemiluminescence (CL) sensor for isoniazid combined with flow-inje ction technology is presented in this paper. The analytical reagents, lumin ol and ferricyanide, were both immobilized on an anion-exchange column. The CL signal produced by the reaction between luminol and ferricyanide, which were eluted from the column through sodium phosphate injection, was decrea sed in the presence of isoniazid. The decreased CL intensity was linear wit h isoniazid concentration in the range 0.001-1.0 ng . ml(-1); and the detec tion limit was 0.35 mug . ml(-1) (3s). The whole process, including samplin g and washing, could be completed in 2 min with a relative standard deviati on of less than 4.1%. The sensor could be reused more than 400 times and ha s been applied for the determination of isoniazid in pharmaceutical prepara tions. (C) 2001 Elsevier Science B.V. All rights reserved.