College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming 650092, China.
College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming 650092, China.
Int J Biol Macromol. 2023 Apr 1;233:123570. doi: 10.1016/j.ijbiomac.2023.123570. Epub 2023 Feb 8.
Hybrid hydrogels containing biomacromolecules have been widely used in sensors, fluorescent probes, and other fields due to their high biocompatibility and nontoxicity. In this paper, tough hydrogels with interconnected macro-pores have been fabricated by freeze-induced chemical cross-linking of microfibrillated cellulose (MFC) and organic modified chitosan (CS). In this hydrogel materials, three-dimensional networks were formed by abundant hydrogen bonds and chemical cross-linking. Luminescent lanthanide complexes were covalently bonded to the hydrogel networks through coordination of Eu ions with 2, 3-pyridine dicarboxylic acid modified chitosan. The luminescence of hydrogel materials was further improved by the replacement of coordination water with 2-thiophenyltrifluoroacetone (TTA). The prepared hydrogels showed excellent shape memory properties both under water and in air. The stress of the hybrid hydrogel at 80 % strain can reach 159 kPa, which is much higher than that of the traditional microfibrillated cellulose-based hydrogels. The obtained luminescent hybrid hydrogels exhibited an excellent fluorescence detection effect on formaldehyde. The detection limit for formaldehyde is 45.7 ppb, which is much lower than the WHO standard (80 ppb for indoor air). The novel, facile preparing procedure may extend the potential applications of hybrid lanthanide luminescent hydrogel as fluorescence probes for pollution monitoring, especially for formaldehyde and other organic aldehydes.
由于具有生物相容性和低毒性，含有生物大分子的杂化水凝胶已广泛应用于传感器、荧光探针等领域。本文通过冷冻诱导的微纤化纤维素（MFC）和有机改性壳聚糖（CS）的化学交联制备了具有互穿大孔的坚韧水凝胶。在这种水凝胶材料中，丰富的氢键和化学交联形成了三维网络。通过 Eu 离子与 2,3-吡啶二甲酸改性壳聚糖的配位，将发光镧系配合物共价键合到水凝胶网络中。通过用 2-噻吩三氟乙酰丙酮（TTA）取代配位水，进一步提高了水凝胶材料的发光性能。所制备的水凝胶在水和空气中均表现出优异的形状记忆性能。杂化水凝胶在 80%应变下的应力可达 159 kPa，远高于传统的基于微纤化纤维素的水凝胶。所得发光杂化水凝胶对甲醛表现出优异的荧光检测效果。甲醛的检测限为 45.7 ppb，远低于世界卫生组织标准（室内空气 80 ppb）。这种新颖、简便的制备方法可能会扩展杂化镧系发光水凝胶作为荧光探针用于污染监测的潜在应用，特别是用于检测甲醛和其他有机醛。
