Enzyme field effect transistor (ENFET) for estimation of triglycerides using magnetic nanoparticles.
Enzyme field effect transistor (ENFET) for estimation of triglycerides using magnetic nanoparticles.
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DOI：
10.1016/j.bios.2008.02.003
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发表时间：
2008-06
影响因子：
12.6
通讯作者：
A. Vijayalakshmi;Y. Tarunashree;B. Baruwati;S. Manorama;B. Narayana;Rebecca Lynn Johnson;N. Rao
中科院分区：
文献类型：
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作者：
A. Vijayalakshmi;Y. Tarunashree;B. Baruwati;S. Manorama;B. Narayana;Rebecca Lynn Johnson;N. Rao
离子选择场效应晶体管(ISFET)是发展生物传感器的有力平台。使用各种方法，包括共价连接或聚合物包埋，将酶或抗体与FET的栅极表面相关联。我们采用了一种新的方法来将酶分子保留在栅极表面，方法是将酶固定在磁性镍铁氧体纳米颗粒上，并在FET栅下施加永久磁铁。通过将耐热脂肪酶固定在纳米颗粒上，我们能够估计甘油三酯浓度在0.1-1.5%的范围内。三丁酸三酯、三辛酸酯和三酸三油酯也给出了类似的结果。反应体积可以缩小到0.2ml，而不会损失斜率或灵敏度。离子强度(>；150 mMNaC l)对测量的灵敏度有很大影响。这种结构的酶生物传感器的优点是减少了传质问题，增加了门表面的酶的量，并提供了使用单个FET设备检测多个分析物的机会。
Ion-selective field effect transistor (ISFET) is a robust platform to develop biosensors. A variety of methods are used including covalent attachment or polymer entrapment, to associate enzymes or antibodies to the gate surface of a FET. We have employed a novel method of retaining the enzyme molecules at the gate surface by immobilizing the enzyme on magnetic nickelferrite nanoparticles and applying a permanent magnet below the gate of the FET. We were able to estimate the triglyceride concentrations in the range of 0.1–1.5% by immobilizing a thermostable lipase on nanoparticles. Tributyrin, trioctanoate and triolein have given similar results. The reaction volume could be scaled down to 0.2ml without a loss in slope or sensitivity. Ionic strength (>150mM NaCl) has a strong influence on the sensitivity of the measurement. The advantages of this configuration of enzyme biosensor are reduction of mass transfer problems, increasing the amount of enzyme at the gate surface besides providing an opportunity to use a single FET device for multiple analyte detection.