Abstract This paper presents an iodine ions fluorescence quenching sensor based on hydrogel fiber doped with fluorescein. The hydrogel fiber was made by photo-crosslinking with core-cladding structure made from PEGDA precursor solutions with different concentration. Compared with calcium alginate cladding material, this structure is less susceptible to damage and the thickness of the cladding is controllable, which significantly reduces the loss of the hydrogel fiber. Experimental results show that the loss of the cladding-free hydrogel is 1.669 dB/cm ± 0.4 dB/cm, and the loss of the core-cladding hydrogel fiber is 0.597 dB/cm ± 0.2 dB/cm. By analyzing the properties of different hydrogel precursor solutions before and after photo-crosslinking, a functional hydrogel fiber doped with fluorescein for measuring iodine ions with numerical aperture of 0.3932 and mode number about 17 was fabricated. The hydrogel fiber shows high coupling efficiency with PMMA plastic optical fiber. The sensor of iodine ions exhibited a linear range of 0 ∼ 36 mM and the detection limit was calculated to be 26nM. The system also shows good stability and repeatability. Hydrogel fibers shows good biocompatibility and flexibility, which will have broad application prospects in biological area in the future.

中文翻译：

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基于荧光猝灭法和荧光素掺杂水凝胶光纤的碘离子传感

摘要 本文提出了一种基于掺杂荧光素的水凝胶光纤的碘离子荧光猝灭传感器。水凝胶纤维是通过光交联与由不同浓度的 PEGDA 前驱体溶液制成的芯包层结构制成的。与海藻酸钙包层材料相比，这种结构不易损坏，包层厚度可控，显着降低了水凝胶纤维的损耗。实验结果表明，无包层水凝胶的损耗为1.669 dB/cm ± 0.4 dB/cm，纤芯包层水凝胶光纤的损耗为0.597 dB/cm ± 0.2 dB/cm。通过分析光交联前后不同水凝胶前驱体溶液的性质，制备了一种掺有荧光素的功能性水凝胶光纤，用于测量碘离子，数值孔径为 0.3932，模数约为 17。水凝胶光纤与 PMMA 塑料光纤显示出高耦合效率。碘离子传感器的线性范围为 0 ∼ 36 mM，计算出的检测限为 26nM。该系统还显示出良好的稳定性和可重复性。水凝胶纤维显示出良好的生物相容性和柔韧性，未来在生物领域具有广阔的应用前景。