Abstract：
BACKGROUND:Reports of the use of multiplex enzyme assay screening for Pompe disease, Fabry disease, Gaucher disease, Niemann-Pick disease types A and B, and Krabbe disease have engendered interest in the use of this assay in newborn screening. We modified the assay for high-throughput use in screening laboratories. METHODS:We optimized enzyme reaction conditions and procedures for the assay, including the concentrations of substrate (S) and internal standard (IS), assay cocktail compositions, sample clean-up procedures, and mass spectrometer operation. The S and IS for each enzyme were premixed and bottled at an optimized molar ratio to simplify assay cocktail preparation. Using the new S:IS ratio, we validated the modified assay according to CLSI guidelines. Stability of the S, IS, and assay cocktails were investigated. Dried blood spots from 149 healthy adults, 100 newborns, and 60 patients with a lysosomal storage disorder (LSD) were tested using the modified assay. RESULTS:In our study, the median enzyme activity measured in adults was generally increased 2-3-fold compared to the original method, results indicating higher precision. In the multiplex format, each of the 5 modified enzyme assays enabled unambiguous differentiation between samples from healthy individuals (adults and newborns) and the corresponding disease-specific samples. CONCLUSIONS:The modified multiplex enzyme assay with premixed S and IS is appropriate for use in high-throughput screening laboratories.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Zhang XK,Elbin CS,Chuang WL,Cooper SK,Marashio CA,Beauregard C,Keutzer JMdoi
10.1373/clinchem.2008.104711subject
Has Abstractpub_date
2008-10-01 00:00:00pages
1725-8issue
10eissn
0009-9147issn
1530-8561pii
clinchem.2008.104711journal_volume
54pub_type
杂志文章abstract：:Use of an 125I radioimmunoassay involving antiserum coupled to magnetizable cellulose, after prednisolone-21-phosphate interference is removed by dichloromethane extraction at pH 7.4 and endogenous glucocorticoid interference is removed by selective chemical derivatization with Girard's Reagent T [(carboxymethyl)trime...
journal_title：Clinical chemistry
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journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章
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doi：10.1373/clinchem.2007.096032
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journal_title：Clinical chemistry
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更新日期：1986-02-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1977-09-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1991-08-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1987-12-01 00:00:00
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journal_title：Clinical chemistry
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更新日期：1978-09-01 00:00:00
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doi：
更新日期：1997-11-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1988-01-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1993-05-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1981-05-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1987-04-01 00:00:00
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doi：
更新日期：1975-02-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1984-06-01 00:00:00
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pub_type： 临床试验,杂志文章
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journal_title：Clinical chemistry
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doi：
更新日期：1983-10-01 00:00:00
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doi：
更新日期：1988-09-01 00:00:00
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doi：
更新日期：1990-01-01 00:00:00
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doi：
更新日期：1989-07-01 00:00:00
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doi：
更新日期：1984-04-01 00:00:00
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更新日期：2001-01-01 00:00:00
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doi：
更新日期：1978-09-01 00:00:00
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更新日期：1994-11-01 00:00:00
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doi：
更新日期：1975-12-01 00:00:00
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