Herein, we report a polyaniline-nickel oxide (PANI-NiO) nanocomposite as an efficient immobilization matrix for development the optical fiber urea biosensor. Optical fiber sensing probe was developed by removing some portion of optical fiber at middle and modified with PANI-NiO matrix. After the modification of cladding removed portion, it was immobilized with enzyme urease via glutaraldehyde as a bi-functional cross-linking agent. The physicochemical and optical properties of the PANI-NiO matrix were explored by X-ray diffraction, scanning electron microscopy, ultraviolet–visible, and Fourier transform infrared spectroscopic techniques. The characteristic features and performance of the developed sensor were evaluated via recording the output power and modal power distribution by means of a charge-coupled device camera. The developed urea biosensor exhibits a selective response towards urea concentrations in the linear range 1 nM–100 mM with a lower detection limit of 1 nM. Sensor recorded as a 40 days stability and response time ~1 min. Thus, the obtained experimental results of the developed sensor promote its applicability with practical prospects in diverse field.

中文翻译：

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脲酶固定本征光纤尿素生物传感器修饰的超灵敏聚苯胺-氧化镍包层

在此，我们报告了聚苯胺-氧化镍 (PANI-NiO) 纳米复合材料作为开发光纤尿素生物传感器的有效固定基质。光纤传感探头是通过去除中间部分光纤并用PANI-NiO基体改性而开发的。包层去除部分修饰后，通过戊二醛作为双功能交联剂用脲酶固定。通过 X 射线衍射、扫描电子显微镜、紫外-可见光和傅里叶变换红外光谱技术研究了 PANI-NiO 基体的物理化学和光学性质。通过电荷耦合器件相机记录输出功率和模态功率分布来评估所开发传感器的特性和性能。开发的尿素生物传感器对线性范围 1 nM–100 mM 的尿素浓度具有选择性响应，检测下限为 1 nM。传感器记录为 40 天的稳定性和响应时间 ~1 分钟。因此，所开发的传感器获得的实验结果促进了其在不同领域的实用性和实际前景。