基于MoS_(2)-Fe_(3)O_(4)复合物水凝胶的过氧化氢比色检测

Colorimetric detection of H2O2 based on MoS_(2)-Fe_(3)O_(4) composite hydrogel

水体中残留的H_(2)O_(2)进入人体后会转化为含氧自由基,进而对机体造成氧化损伤并引发病变,因此实现水体中的H_(2)O_(2)检测具有重要意义.制备了具有较高类过氧化物酶活性的MoS_(2)-Fe_(3)O_(4)复合物水凝胶,并构建比色传感平台实现了水体中H_(2)O_(2)的灵敏检测.在H_(2)O_(2)-TMB显色体系中,Fe_(3)O_(4)与MoS_(2)纳米片复合协同催化H_(2)O_(2)产生含氧自由基,水凝胶三维结构可有效抑制MoS_(2)-Fe_(3)O_(4)堆叠,促进活性位点的暴露,进一步提高对H_(2)O_(2)的催化能力.动力学常数显示,MoS_(2)-Fe_(3)O_(4)复合物水凝胶催化H_(2)O_(2)底物的最大速度是辣根过氧化物酶(HRP)的1.5倍.基于较高的H_(2)O_(2)催化活性,水体中H_(2)O_(2)检测限达到0.28μmol/L,检测线性范围为3.0~200μmol/L,并采用加标回收法对自来水、湖水和海水等实际水体中的H_(2)O_(2)进行了检测.

H_(2)O_(2)residual in water will be converted into oxygen-containing free radicals after entering body,which will cause oxidative damage to body and pathological changes.Therefore,it is of great significance for H_(2)O_(2)detection in water.MoS_(2)-Fe_(3)O_(4)composite hydrogel with remarkably enhanced peroxidase-like catalytic activity is synthesized,and the sensitive detection of H_(2)O_(2)in water is realized through the construction of colorimetric sensors platform.In the H_(2)O_(2)-TMB color system,the generation of oxygen-containing free radicals by H_(2)O_(2)is catalyzed by MoS_(2) and Fe_(3)O_(4) nanosheets synergistically.Meanwhile,the construction of 3D structure of hydrogel can inhibit the stacking of MoS_(2)-Fe_(3)O_(4),which is benefit for the exposure of active sites,and highly enhance catalytic activity for H_(2)O_(2).The kinetic constants show that MoS_(2)-Fe_(3)O_(4)composite hydrogel has maximum catalytic velocity for substrates of H_(2)O_(2),which is about 1.5 times higher than that of HRP(horseradish peroxidase).Based on high catalytic activity for H_(2)O_(2),detection is conducted with a linear relationship between absorbance and H_(2)O_(2)concentrations,ranging from 3.0 to 200μmol/L,and the limit of detection(LOD)is 0.28μmol/L.H_(2)O_(2)in running water,lake,sea is detected by marking recovery method.