Dopamine, hydrogen peroxide determination

HPLC on a Cosmosil 5 Cis column, using a perchloric acid-acetonitrile eluent (pH 7.6), followed by CLD in the presence of hydrogen peroxide and bis(2,4,6-trichlorophenyl) oxalate (42), was applied to the determination of 1-aminopyrene (43a) and various diaminopyrenes (43b-d). Ascorbic acid was added to avoid oxidative degradation of the aminopyrenes in the presence of metals LOD in the sub-fmol range (SNR 3)147. A fast (less than 10 min) HPLC-ELCD method was proposed for determination of dopamine (19b) and its metabolites in microdialysates, using packed fused silica capillary columns LOD 0.05 Xg/L of dopamine in a 2 XL sample, RSD 3% (n = 10)148. 

Lucigenin is the next most frequently used emitter for the determination of isoprenaline or kanamycin by inhibition of the lucigenin-hydrogen peroxide-cobalt(II) system, and also for the determination of the trace amounts of dopamine. The chemiluminescent determination of protein in a micellar medium using FIA employs offline labeling of albumin by sonicating a mixture of 1 ml of albumin in NaHC03 (pH 11.5) and fluorescamine in acetone for 1 min at room temperature. 

Generally, AA is determined individually, and only about a 10% of the published methods determine AA simultaneously with other analytes such as uric acid, glucose, fructose, dopamine, iodate, bromate, hypochlorite, thiourea, glutathione, hydrogen peroxide, acetylsalicylic acid, kojic acid, ascorbyl glucoside, paracetamol, cysteine, and other water soluble vitamins (thiamine [vitamin Bj], folic acid [vitamin B12], niacin [vitamin B3], riboflavin [vitamin B2], and pyridoxine [vitamin B ]). 

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