The significance of easily detecting rare earth elements (REEs) has increased due to the growing demand for REEs. Addressing this need, we present an innovative electrochemical biosensor, focusing on cerium as a model REE. This biosensor utilizes a modified EF-hand loop peptide sequence, incorporating cysteine for covalent attachment to a gold working electrode and tyrosine as an electrochemically active amino acid. The sensor was designed such that binding to cerium induces a conformational change in the peptide, affecting tyrosine's proximity to the electrode surface, modulating the current. A calibration curve was generated from cyclic voltammetry current peaks at ~0.55–0.65 V versus a silver pseudo-reference electrode, with cerium concentrations ranging from 0 to 67 μM in artificial urine. The sensor exhibited a biologically relevant limit of detection of 35 μM and a sensitivity of −0.0024 ± 0.002 (μA μM)⁻¹. These findings offer insights into designing peptide sequences for electrochemical biosensing.

中文翻译：

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使用酪氨酸功能化的 EF 手环肽对铈进行电化学生物传感


由于对稀土元素的需求不断增长，轻松检测稀土元素 （REE） 的重要性也随之增加。为了满足这一需求，我们提出了一种创新的电化学生物传感器，专注于铈作为模型 REE。该生物传感器利用修饰的 EF 手环肽序列，结合半胱氨酸以共价连接到金工作电极上，并结合酪氨酸作为电化学活性氨基酸。该传感器的设计使得与铈结合会诱导肽的构象变化，从而影响酪氨酸靠近电极表面，从而调节电流。根据 ~0.55–0.65 V 的循环伏安电流峰值与银伪参比电极的对比生成校准曲线，人工尿液中的铈浓度范围为 0 至 67 μM。该传感器的生物学相关检测限为 35 μM，灵敏度为 -0.0024 ± 0.002 （μA μM）^-1。这些发现为设计电化学生物传感的肽序列提供了见解。