Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A validated method for determination of total amount of ketotifen (unchanged and conjugated) in human plasma has been presented. An enzyme hydrolysis of conjugated ketotifen was conducted with combination of beta-glucuronidase and arylsulfatase. After the enzyme hydrolysis a solid-phase extraction was applied as a cleaning step. The quantitative determination by gas chromatography with mass-spectrometry detection (GC-MS) was performed. Pizotifen has been used as an internal standard. A reliable hydrolysis as well as a satisfactory accuracy, improved precision in the linear region from 0.500 to 10.0 ng/ml plasma, limit of detection of 0.010 ng/ml and prolonged capillary column life have been achieved.
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PMID:Gas chromatographic-mass spectrometric method for quantitative determination of ketotifen in human plasma after enzyme hydrolysis of conjugated ketotifen. 1051 44

Analytical validation of a new liquid chromatographic-mass spectrometric (LC-MS) method for determination of total amount of ketotifen (unchanged and conjugated) in human plasma is presented. Pizotifen was used as an internal standard. An enzyme hydrolysis of conjugated ketotifen was conducted with a combination of beta-glucuronidase and aryl sulfatase. After enzyme hydrolysis a liquid-liquid extraction was performed as a cleaning step. The quantitative determination was obtained using selected ion monitoring (SIM) LC-MS. Chromatographic condition was a combination of reverse phase gradient system and a switching column technique. A satisfactory hydrolysis, acceptable accuracy, improved precision in the linear range from 0.5 to 20.0 ng/ml plasma, absolute recovery of 98.04% for ketotifen and 95.13% for pizotifen and stability for 7 months at -20 degrees C have been achieved.
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PMID:Determination of ketotifen in human plasma by LC-MS. 1473 22