Enzymatic Probe Sonication: Enhancement of Protease-Catalyzed Hydrolysis of Selenium Bound to Proteins in Yeast
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- 作者：J. L. Capelo ; P. Ximé ; nez-Embú ; n ; Y. Madrid-Albarrá ; n ; and C. Cá ; mara
- 刊名：Analytical Chemistry
- 出版年：2004
- 出版时间：January 1, 2004
- 年：2004
- 卷：76
- 期：1
- 页码：233 - 237
- 全文大小：55K
- 年卷期：v.76,no.1(January 1, 2004)
- ISSN：1520-6882
文摘
This paper describes the dramatic activity enhancementof two proteolytic enzymes (protease XIV and subtilisin)when treated with an ultrasonic probe and their application to total Se determination and Se speciation in biological samples. Total Se extraction from enriched yeast isperformed with 10 mg of yeast plus 1 mg of protease witha sonication time of 5 s, whereas 30 s is needed forextracting selenomethionine. In both cases, aqueousmedia was used. This spectacular finding is importantbecause the enzymatic procedure usually requires a longtreatment period at 37 
C. In addition to this majoradvantage, no control temperature is needed and the riskof species interconversion is drastically reduced or inhibited (the same Se species were detected after differentsonication times). Moreover, the extraction is performedin water, minimizing contamination risk and withoutfurther pH adjustment. The new sample treatment proposed has been successfully applied to selenium speciation in yeast using chromatographic separation (HPLC)coupled to inductively coupled plasma-mass spectrometry.
C. In addition to this majoradvantage, no control temperature is needed and the riskof species interconversion is drastically reduced or inhibited (the same Se species were detected after differentsonication times). Moreover, the extraction is performedin water, minimizing contamination risk and withoutfurther pH adjustment. The new sample treatment proposed has been successfully applied to selenium speciation in yeast using chromatographic separation (HPLC)coupled to inductively coupled plasma-mass spectrometry.