Yang Zhengpeng, Si Shihui, Dai Hongjuan, Zhang Chunjing
College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
Biosens Bioelectron. 2007 Jun 15;22(12):3283-7. doi: 10.1016/j.bios.2007.03.006. Epub 2007 Mar 14.
The urease was immobilized onto nanoporous alumina membranes prepared by the two-step anodization method, and a novel piezoelectric urea sensing system with separated porous alumina/urease electrode has been developed through measuring the conductivity change of immobilized urease/urea reaction. The process of urease immobilization was optimized and the performance of the developed urea biosensor was evaluated. The obtained urea biosensor presented high-selectivity monitoring of urea, better reproducibility (S.D.=0.02, n=6), shorter response time (30s), wider linear range (0.5 microM to 3mM), lower detection limit (0.2 microM) and good long-term storage stability (with about 76% of the enzymatic activity retained after 30 days). The clinical analysis of the urea biosensor confirmed the feasibility of urea detection in urine samples.
脲酶被固定在通过两步阳极氧化法制备的纳米多孔氧化铝膜上，并通过测量固定化脲酶/尿素反应的电导率变化，开发了一种具有分离的多孔氧化铝/脲酶电极的新型压电尿素传感系统。优化了脲酶固定化过程，并评估了所开发的尿素生物传感器的性能。所获得的尿素生物传感器对尿素具有高选择性监测、更好的重现性（标准偏差=0.02，n=6）、更短的响应时间（30秒）、更宽的线性范围（0.5微摩尔至3毫摩尔）、更低的检测限（0.2微摩尔）以及良好的长期储存稳定性（30天后保留约76%的酶活性）。尿素生物传感器的临床分析证实了在尿液样本中检测尿素的可行性。
