Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0393754 (HSA)
 2,996 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The preparation and optimization of a new monolithic chymotrypsin bioreactor for online protein digestion is described. Silica monolithic supports have been activated with epoxide functionalities following an optimized in situ procedure and used for covalent immobilization of chymotrypsin in one-step reaction under different conditions. A total of four bioreactors were prepared and characterized in terms of the amount of immobilized enzyme and apparent active units by using a standard substrate, N-benzoyl-L-tyrosine p-nitroanilide (BTPNA). The stability of the bioreactors was evaluated and the morphology of the support after immobilization and use was studied by SEM analysis. The proteolytic activity of the optimized chymotrypsin bioreactor was evaluated using HSA as a model protein by online coupling of the bioreactor with LC-ESI-MS. With the online protocol, complete protein digestion in 120 min was achieved with a sequence coverage of 97.3%.
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PMID:Chymotrypsin immobilization on epoxy monolithic silica columns: development and characterization of a bioreactor for protein digestion. 1792 85

In acetate buffer solution and in the presence of glucose oxidase (GOD), glucose reduced the dissolved oxygen to form H2O2 that oxidized catalytically the excess KI to from I3- by horseradish peroxidase (HRP). The I3- combines respectively with rhodamine S (RhS), rhodamine 6G(Rh6G), butyl-rhodamine B(b-RhB) and rhodamine B(RhB) to form RhS-I3, Rh6G-I3, b-RhB-I3 and RhB-I3 associated particles that result in fluorescence quenching at 556, 556, 584 and 584 nm, respectively. Under the optimal conditions, the concentration of glucose in the range of 0.083-9.99, 0.17-8.33, 0.33-8.33 and 0.33-9.99 micromol x L(-1) is linear with their fluorescence quenching at 556, 556, 584 and 584 nm, with detection limits of 0.059, 0.17, 0.21 and 0.16 micromol x L(-1) glucose. And the regression equation was deltaF = 40.0c + 3.0, deltaF = 23.9c + 8.1, deltaF = 25.6c + 4.2, and deltaAF = 18.4c + 0.8, respectively. The RhS system was the most sensitive and stable, and was chosen for use. Influence of some foreign substances on the RhS fluorescence quenching determination of 6.67 micromol x L(-1) glucose was examined, with a relative error of +/- 10%. Results showed that 1000-fold Mg2+ and Cu2+, 300-fold Mn2+, 100-fold Zn2+, Al3+ and Co2+, 60-fold L-tyrosine, urea and nicotinic acid, 50-fold Fe3+, HSA and BSA, 10-fold sucrose, vitamin B2, L-lysine, L-glutamic acid and L-cystine did not interfere with the determination. This RhS fluorescence quenching assay was applied to the determination of glucose in the serum samples with satisfactory results.
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PMID:[Fluorescence analysis of trace glucose using glucose oxidase and horseradish peroxidase]. 1995 Jun 69