Electroanalytical Chemistry Research Laboratory, Department of Analytical Chemistry, Faculty of Chemistry, University of Mazandaran, Babolsar, Iran.
Electroanalytical Chemistry Research Laboratory, Department of Analytical Chemistry, Faculty of Chemistry, University of Mazandaran, Babolsar, Iran.
Int J Biol Macromol. 2018 Jul 1;113:648-654. doi: 10.1016/j.ijbiomac.2018.02.060. Epub 2018 Feb 12.
In this paper, a new and facile method for the electrochemical determination of l-tyrosine was designed. First, 3-mercaptopropyl trimethoxysilane-functionalized silica nanoparticles were added to a paper disc. Then, the banana peel tissue and the mediator potassium hexacyanoferrate were dropped onto the paper, respectively. The modified paper disc was placed on the top of the graphite screen printed electrode and electrochemical characterization of this biosensor was studied by cyclic voltammetry and electrochemical impedance spectroscopy methods. The effective parameters like pH, banana peel tissue percentage, and the amount of mediator loading were optimized. l-tyrosine measurements were done by differential pulse voltammetry with a little sample (3 μL) for analysis. The biosensor showed a linear response for l-tyrosine in the wide concentration range of 0.05-600 μM and a low detection limit about 0.02 μM because of the co-catalytic effect of enzyme and nanoparticles. The stability of the biosensor and its selectivity were evaluated. This biosensor was applied for the voltammetric determination of l-tyrosine in the blood plasma sample. The results of the practical application study were comparable with the standard method (HPLC). In conclusion, a simple, inexpensive, rapid, sensitive and selective technique was successfully applied to the l-tyrosine analysis of the little samples.
本文设计了一种新的、简便的电化学测定 l-酪氨酸的方法。首先，将 3-巯丙基三甲氧基硅烷功能化的硅胶纳米粒子添加到纸盘上。然后，分别将香蕉皮组织和介体铁氰化钾滴到纸上。将修饰后的纸盘放在石墨印刷电极的顶部，通过循环伏安法和电化学阻抗谱法研究该生物传感器的电化学特性。优化了有效参数，如 pH 值、香蕉皮组织的百分比和介体加载量。通过差分脉冲伏安法对 l-酪氨酸进行了测量，只需分析少量样品（3μL）。由于酶和纳米粒子的协同催化作用，该生物传感器在 0.05-600μM 的宽浓度范围内对 l-酪氨酸表现出线性响应，检测限约为 0.02μM。评估了生物传感器的稳定性和选择性。该生物传感器已应用于测定血浆样品中的 l-酪氨酸。实际应用研究的结果与标准方法（HPLC）相当。总之，成功地将一种简单、廉价、快速、灵敏和选择性的技术应用于小样本的 l-酪氨酸分析。
