A flow injection method is reported for the determination of sulphite-based on chemiluminescent detection. Hydrogen peroxide is produced from sulphite using on-line covalently bound immobilized sulphite oxidase packed in a mini-column, which was mixed downstream and detected via cobalt(II)-catalysed chemiluminescent oxidation of luminol. The limit of detection (2 x standard deviation of the blank) was 1 x 10(-3) mmol/L with sample throughput 60 h(-1). The calibration data was linear over the range of 0.2-1.0 mmol/L with relative standard deviation (n = 4) in the range 0.9-2.0%.

Cobalt↗

PubMedDate not supplied

Determination of iron in blood serum using flow injection with luminol chemiluminescence detection.

A simple and rapid fl ow injection method is reported for the determination of iron in blood serum after acid digestion with HNO3 and HClO4, based on luminol CL detection in the absence of added oxidant. The detection limit (3 s) was 1.0 nmol/L with a sample throughput of 120/h. The calibration graph was linear over the range 0.001-1.0 micromol/L (r2 = 0.9974), with relative standard deviations (RSD) (n = 4) in the range 3.2-5%. The effect of interfering cations (Ca(II), Mg(II), Cu(II), Cd(II), Pb(II), Mn(II), Zn(II), Ni(II), Co(II) and Fe(III)) and anions (Cl-, SO4(2-), HCO3-, NO3-, NO2-) were studied using a luminol CL system for Fe(II) determination. The method was applied to normal blood serum and the results (1.32 +/- 0.08-1.74 +/- 0.05 mg/L) were compared with those from a spectrophotometric reference method (1.34 +/- 0.06-1.80 +/- 0.10 mg/L), which agree fairly well with the overall reference range in blood.

Borates↗