Determination of bilirubin in liver homogenates and serum with diazotized p-iodoaniline
EP Van Roy, JATP Meuwissen, F De Meuter… - Clinica Chimica …, 1971 - Elsevier
EP Van Roy, JATP Meuwissen, F De Meuter, KPM Heirwegh
Clinica Chimica Acta, 1971•Elsevier1. Using the diazonium salt of p-iodoaniline, bile pigments present in aqueous solution and
in protein-containing systems are diazotized when the system acetoneethanol (1: 1, v/v) is
used for accelerating the reaction. After terminating the reaction with ascorbic acid the azo-
pigments are quantitatively extracted into n-butyl acetate, and their concentration
determined photometrically. Increased selectivity can be obtained by further transforming the
azo-pigments into their Zn 2+ complexes. 2. 2. Within wide limits colour formation and …
in protein-containing systems are diazotized when the system acetoneethanol (1: 1, v/v) is
used for accelerating the reaction. After terminating the reaction with ascorbic acid the azo-
pigments are quantitatively extracted into n-butyl acetate, and their concentration
determined photometrically. Increased selectivity can be obtained by further transforming the
azo-pigments into their Zn 2+ complexes. 2. 2. Within wide limits colour formation and …
Abstract
- 1.1. Using the diazonium salt of p-iodoaniline, bile pigments present in aqueous solution and in protein-containing systems are diazotized when the system acetoneethanol (1 : 1, v/v) is used for accelerating the reaction. After terminating the reaction with ascorbic acid the azo-pigments are quantitatively extracted into n-butyl acetate, and their concentration determined photometrically. Increased selectivity can be obtained by further transforming the azo-pigments into their Zn2+ complexes.
- 2.2. Within wide limits colour formation and extraction are independent of serum protein concentration and of the extraction volume: sample volume ratio. Recovery of unconjugated bilirubin from 10% (w/v) homogenates of perfused rat liver amounted to 93%, at bilirubin concentrations near 35 mg/1.
- 3.3. The extraction step renders blank values very low. The reproducibility and the sensitivity of the methods are adequate.
- 4.4. The azo-pigment extracts can be applied directly to thin layer plates and separated rapidly into the conjugated and unconjugated azobilirubin derivatives.
- 5.5. With these methods normal serum bilirubin levels can be determined accurately, and the presence of conjugated bilirubin demonstrated unequivocally even when the total bilirubin concentration is in the normal range.
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