环境监测、食品工业、临床、制药等领域对过氧化氢(H_2O_2)的快速、准确检测有极大的需求,而电化学检测方法由于灵敏度高、响应快、检测限低等特点被认为是最理想的H_2O_2检测方法.本文利用电化学沉积的方法将Pd纳米颗粒沉积到四氧化三...环境监测、食品工业、临床、制药等领域对过氧化氢(H_2O_2)的快速、准确检测有极大的需求,而电化学检测方法由于灵敏度高、响应快、检测限低等特点被认为是最理想的H_2O_2检测方法.本文利用电化学沉积的方法将Pd纳米颗粒沉积到四氧化三铁/石墨烯(Fe_3O_4/rGO)纳米复合材料修饰的玻碳电极表面,形成基于新型磁性纳米复合材料的H_2O_2无酶传感器;并采用循环伏安和计时安培电流等方法对修饰电极的电化学性能进行了表征.结果表明:制备的Pd/Fe_3O_4/r GO/GCE对H_2O_2的催化还原显示出较好的电催化活性,Pd纳米颗粒和Fe_3O_4/rGO在催化H_2O_2还原的过程中表现出了良好的协同作用.测定H_2O_2的线性范围为0.05~1 m M和1~2.6 m M两段,最低检测限达到3.918μM(S/N=3).并且该传感器具有较高的灵敏度和较好的重现性和抗干扰性,具有一定的实际应用价值.展开更多
An electrochemical biosensing platform was developed based on glucose oxidase(GOx)/Fe3O4-reduced graphene oxide(Fe3O4-RGO) nanosheets loaded on the magnetic glassy carbon electrode(MGCE).With the advantages of the mag...An electrochemical biosensing platform was developed based on glucose oxidase(GOx)/Fe3O4-reduced graphene oxide(Fe3O4-RGO) nanosheets loaded on the magnetic glassy carbon electrode(MGCE).With the advantages of the magnetism, conductivity and biocompatibility of the Fe3O4-RGO nanosheets, the nanocomposites could be facilely adhered to the electrode surface by magnetically controllable assembling and beneficial to achieve the direct redox reactions and electrocatalytic behaviors of GOx immobilized into the nanocomposites. The biosensor exhibited good electrocatalytic activity, high sensitivity and stability. The current response is linear over glucose concentration ranging from 0.05 to 1.5 m M with a low detection limit of0.15 μM. Meanwhile, validation of the applicability of the biosensor was carried out by determining glucose in serum samples. The proposed protocol is simple, inexpensive and convenient, which shows great potential in biosensing application.展开更多
Reduced graphene oxide-Fe3O4(rGO—Fe3O4) composite has been prepared via a facile and effective hydrothermal method by synthesizing Fe3O4 nanospheres on the planes of reduced graphene oxide(rGO).Characterizations ...Reduced graphene oxide-Fe3O4(rGO—Fe3O4) composite has been prepared via a facile and effective hydrothermal method by synthesizing Fe3O4 nanospheres on the planes of reduced graphene oxide(rGO).Characterizations suggest the successful attachment of Fe3O4 nanospheres to rGO sheets.The rGO—Fe3O4composite(66.7 wt%of Fe3O4 in the composite) exhibits a stable capacity of 668 mAh g-1 without noticeable fading for up to 200 cycles in the voltage range of 0.001—3.0 V,and the superior performance of rGO-Fe3O4 is clearly established by comparison of the results with those from bare Fe3O4 nanospheres(capacity declined to 117 mAh g-1 only at the 200 th cycle).The excellent electrochemical performance of rGO—Fe3O4 composite can be attributed to the fact that the uniform dispersion of the Fe3O4 nanospheres growing on the rGO sheets avoids aggregation during Li uptake-release cycling,which is desired for cycle stability.Meanwhile,the rGO sheets afford not only elastic buffer to alleviate the volume variations of Fe3O4nanospheres,but also good ionic and electronic transport medium in the electrode.展开更多
文摘环境监测、食品工业、临床、制药等领域对过氧化氢(H_2O_2)的快速、准确检测有极大的需求,而电化学检测方法由于灵敏度高、响应快、检测限低等特点被认为是最理想的H_2O_2检测方法.本文利用电化学沉积的方法将Pd纳米颗粒沉积到四氧化三铁/石墨烯(Fe_3O_4/rGO)纳米复合材料修饰的玻碳电极表面,形成基于新型磁性纳米复合材料的H_2O_2无酶传感器;并采用循环伏安和计时安培电流等方法对修饰电极的电化学性能进行了表征.结果表明:制备的Pd/Fe_3O_4/r GO/GCE对H_2O_2的催化还原显示出较好的电催化活性,Pd纳米颗粒和Fe_3O_4/rGO在催化H_2O_2还原的过程中表现出了良好的协同作用.测定H_2O_2的线性范围为0.05~1 m M和1~2.6 m M两段,最低检测限达到3.918μM(S/N=3).并且该传感器具有较高的灵敏度和较好的重现性和抗干扰性,具有一定的实际应用价值.
基金supported by the National Natural Science Foundation of China (21373138)Shanghai Sci. & Tech. Committee (12JC1407200)Program for Changjiang Scholars and Innovative Research Team in University (IRT1269)
文摘An electrochemical biosensing platform was developed based on glucose oxidase(GOx)/Fe3O4-reduced graphene oxide(Fe3O4-RGO) nanosheets loaded on the magnetic glassy carbon electrode(MGCE).With the advantages of the magnetism, conductivity and biocompatibility of the Fe3O4-RGO nanosheets, the nanocomposites could be facilely adhered to the electrode surface by magnetically controllable assembling and beneficial to achieve the direct redox reactions and electrocatalytic behaviors of GOx immobilized into the nanocomposites. The biosensor exhibited good electrocatalytic activity, high sensitivity and stability. The current response is linear over glucose concentration ranging from 0.05 to 1.5 m M with a low detection limit of0.15 μM. Meanwhile, validation of the applicability of the biosensor was carried out by determining glucose in serum samples. The proposed protocol is simple, inexpensive and convenient, which shows great potential in biosensing application.
基金supported by the Fundamental Research Funds for the Central Universities(FRF-SD-12-007A)the National Natural Science Foundation of China(No.21276023)
文摘Reduced graphene oxide-Fe3O4(rGO—Fe3O4) composite has been prepared via a facile and effective hydrothermal method by synthesizing Fe3O4 nanospheres on the planes of reduced graphene oxide(rGO).Characterizations suggest the successful attachment of Fe3O4 nanospheres to rGO sheets.The rGO—Fe3O4composite(66.7 wt%of Fe3O4 in the composite) exhibits a stable capacity of 668 mAh g-1 without noticeable fading for up to 200 cycles in the voltage range of 0.001—3.0 V,and the superior performance of rGO-Fe3O4 is clearly established by comparison of the results with those from bare Fe3O4 nanospheres(capacity declined to 117 mAh g-1 only at the 200 th cycle).The excellent electrochemical performance of rGO—Fe3O4 composite can be attributed to the fact that the uniform dispersion of the Fe3O4 nanospheres growing on the rGO sheets avoids aggregation during Li uptake-release cycling,which is desired for cycle stability.Meanwhile,the rGO sheets afford not only elastic buffer to alleviate the volume variations of Fe3O4nanospheres,but also good ionic and electronic transport medium in the electrode.