新型高强度荧光水凝胶探针制备及铁离子检测

Preparation of a novel high strength fluorescent hydrogel sensor and detection of Fe ion

为制备具有优异力学性能的荧光水凝胶,以丙烯酰胺(AM)、聚乙二醇(PEG)和双丙烯酰氧基荧光素(BAcF)为原料,N,N′-亚甲基双丙烯酰胺、过硫酸铵-四甲基乙二胺(APS-TEMED)为氧化还原引发体系,通过自由基聚合制备P(BAcF-AM)/PEG水凝胶.对单体和凝胶的结构进行红外、核磁表征,考察AM浓度、PEG添加量对水凝胶力学性质的影响.结果表明,PEG的加入明显提高了水凝胶的力学性能,当PEG的添加量为AM质量的8%时,水凝胶的拉伸强度达到0.45 MPa,应变达到1190%.同时,该水凝胶在365 nm紫外灯下显现明亮的绿色荧光,并且对水中的一定浓度范围内的Fe3+具有显著的荧光猝灭响应,可以作为潜在的便携式荧光探针材料,检测水中金属离子的浓度.

To prepare fluorescent hydrogels with excellent properties, P(BAcF-AM)/PEG was prepared by free radical solution polymerization with acrylamide(AM), PEG and bis-acryloxyfluorescein(BAcF) as raw material and N,N′-methylene bis-acrylamide, ammonium persulfate-N,N,N′,N′-tetramethylethylenediamine(APS-TEMED)as redox initiator. The structure of monomer and gel were characterized by FTIR and 1HNMR, and the effects of the concentration of AM and amounts of PEG on mechanical properties of hydrogels was studied. The results show that the mechanical properties of the hydrogels are significantly improved by the addition of PEG. When the amount of PEG added is 8% of AM mass, the tensile strength of the hydrogel reaches up to 0.45 MPa, and the strain is about 1190%. At the same time, the hydrogel show bright green fluorescence under 365 nm ultraviolet lamp, and obviously quenches in a certain concentrations range of Fe3+ in water, which can be used to detect the concentration of Fe3+ ions in water as a portable fluorescent probe.