Glucuronides analysis

Nitrophenol and 4-nitrophenol glucuronide are excreted in urine. The studies of urinary excretion of methyl parathion metabolites, including those reported in this section, generally hydrolyze the glucuronide prior to analysis and report the resulting total 4-nitrophenol values. 

The development of class-selective antibodies is another approach to multi-analyte analysis. The analyst may design haptens that will generate antibodies that recognize an epitope common to several compounds, as explained above for the analysis of pyrethroids by measuring PBA. Other examples of class-selective immunoassays that have been developed are mercapturates," glucuronides, pyrethroids, organophosphate insecticides, and benzoylphenylurea insecticides." ... 

R. J., In vitro analysis of human drug glucuronidation and prediction of in vivo metabolic clearance, J. Pharmacol. Exp. Ther. 2002, 301, 382-390. 

R. G. Dickinson, A. R. King, Reactivity Considerations in the Analysis of Glucuronide and Sulfate Conjugates of Diflunisal , Then Drug Monit. 1989, 11, 712 - 720. 

After 36 h (85 % conversion according to HPLC analysis) the solvent was evaporated in vacuo and the residue purified by flash chromatography (eluent AcOEt/MeOH/H20, 8 3 0.5 and then 7 3 1) to give 143 mg (0.247 mmol, 70 % yield) of the glucuronide lb as a yellow solid (7 f = 0.23). 

Kfivankova, L., Caslavska, J., Malaskova, H., Gebauer, P., and Thormann, W. (2004). Analysis of ethyl glucuronide in human serum by capillary electrophoresis with sample self-stacking and indirect detection./. Chromatogr. A 1081, 2 — 8. 

In adult female CFY rats exposed by inhalation (whole-body) to nominal concentrations of 1,000 ppm 1,4-dichlorobenzene, 3 hours a day for 10 days, analysis of metabolites in urine indicated that more than 50% was a sulfate of 2,5-dichlorophenol, and much of the rest was a glucuronide conjugate of... 

Using immobilized -glucuronidase reactors, estriol and estradiol glucuronides have been determined in urine by a column-switching technique (270, 271). Both glucuronides were hydrolyzed by the immobilized enzyme at pH 7. The steroid mixture was subsequently separated by gradient elution on a reversed-phase column, to be finally detected by UV absorbance at 280 nm. In this procedure, the activity of enzyme did not alter even after 150 h continuous run and exposure to a mobile phase containing 10% methanol. When a separate reversed-phase precolumn was inserted in the LC system, additional sample purification and shorter analysis time could be attained (272). 

A postchromatographic -glucuronidase procedure has been also used for the analysis of phenolic glucuronides, such as those produced from trimethoprim (274). The enzymatic analysis of these glucuronides provided the production of the corresponding phenolic compounds, which were measured by both UV and electrochemical detection. 

An indirect enzyme immunoassay suitable for the determination of chloramphenicol and its glucuronide was developed for the analysis of urine, milk, tissue, and eggs as well (48). In this assay, chloramphenicol succinate was coupled to both bovine serum albumin and horseradish peroxidase by a mixed anhydride procedure. Unlike tissue and egg samples, urine and defatted milk could be directly analyzed, but when an ethyl acetate extraction was employed in milk analysis, the limit of detection was lowered at least 10 times. 

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