Wu Zhongli, Xu Heng, He Wenjing, Jian Xiaomin, Zhou Kaicheng, Wang Ya
School of Chemical Engineering, Guizhou Minzu University, Guiyang, 550025, Guizhou, China.
J Fluoresc. 2025 Aug 28. doi: 10.1007/s10895-025-04532-3.
Fluorescent hydrogels have attracted much attention due to their excellent and unique photoluminescent properties, which makes it very necessary to explore their luminescent properties. In this study, a three-dimensional hydrogel system of polyacrylamide-konjac mannan - 2,6-pyridine dicarboxylic acid (PAM-KG-Ln) was constructed using the rare earth element Eu as the luminescence unit, and a series of PKL: xEu fluorescent hydrogels were prepared by in-situ polymerization. The prepared hydrogels had excellent luminescence properties and a color purity of 99.4%. It was found that the strongest emission peaks of PKL: xEu fluorescent hydrogels were located at 700 nm under excitation at 295 and 398 nm., which were derived from the D→F transition. In addition, it was found that the fluorescence quenching phenomenon occurred under the ultraviolet lamp with the increase of Eu doping concentration, and then the spectral analysis combined with Van Uitert modeling revealed that the D energy level quenching mechanism of Eu was dominated by electric dipole-electric dipole interaction (Q ≈ 6), which provides a new paradigm for the design of dynamic fluorescent hydrogels, and is expected to promote the development of applications such as high-resolution biological probes and stimuli-responsive soft drives.
荧光水凝胶因其优异独特的光致发光性能而备受关注，这使得探索其发光性能变得非常必要。在本研究中，以稀土元素铕作为发光单元构建了聚丙烯酰胺-魔芋甘露聚糖-2,6-吡啶二甲酸（PAM-KG-Ln）三维水凝胶体系，并通过原位聚合法制备了一系列PKL:xEu荧光水凝胶。所制备的水凝胶具有优异的发光性能，色纯度达99.4%。研究发现，PKL:xEu荧光水凝胶在295和398nm激发下最强发射峰位于700nm，源于D→F跃迁。此外，研究发现随着铕掺杂浓度增加，在紫外灯下出现荧光猝灭现象，随后结合范乌伊特模型的光谱分析表明，铕的D能级猝灭机制以电偶极-电偶极相互作用为主（Q≈6），这为动态荧光水凝胶的设计提供了新范例，有望推动高分辨率生物探针和刺激响应软驱动器等应用的发展。
