A Novel Immobilized Enzyme Flow-Injection System for Urea with a Bulk Acoustic Wave Impedance Sensor as Detector

Autor:	Huwei Tan, Lili Bao, Xiaoli Su, Shouzhuo Yao, Wanzhi Wei
Rok vydání:	1999
Předmět:	Detection limit Immobilized enzyme Urease biology General Chemical Engineering Detector Analytical chemistry Hydrochloric acid chemistry.chemical_compound Ammonia chemistry Urea biology.protein Ammonium Instrumentation General Environmental Science
Zdroj:	Instrumentation Science & Technology. 27:31-43
ISSN:	1525-6030 1073-9149
DOI:	10.1080/10739149908085828
Popis:	The urea-urease system was chosen as a model system to explore the suitability for the use of a bulk acoustic wave impedance sensor (BAWIS) as a detector in an immobilized enzyme FIA system. In the proposed FIA sysem, the urea in samples was hydrolyzed into ammonium and bicarbonate under the catalysis of the immobilized urease. The ammonium formed was converted into ammonia in an alkaline stream, and the ammonia diffused across a gas-permeable membrane into a recipient solution of dilute hydrochloric acid. The conductance change caused by the trapped ammonia was followed by a BAWIS detector. The system was applied to the analysis of urea in blood and urine samples. It exhibited a linear frequency response up to 10 mM urea with a detection limit of 10 μM. The through-put was 50 h-1, and the relative standard deviation of the peak heights (n=6) ranged between 0.63-1.97%. The effects of several factors, including those affecting the enzymatic reaction, detector performance, and gas-diffusion process...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f9f290f1475c0f24fb6c5b2a7c90e3c2 https://doi.org/10.1080/10739149908085828 Zobrazit plný text záznamu