A new type of sol-gel/organic hybrid composite film based on chitosan(CS) with methytrimethoxysilane(MTOS) was developed for the fabrication of an amperometric glucose biosensor. The hybrid composite film was used to ...A new type of sol-gel/organic hybrid composite film based on chitosan(CS) with methytrimethoxysilane(MTOS) was developed for the fabrication of an amperometric glucose biosensor. The hybrid composite film was used to immobilize glucose oxidase(GOD) on the surface of Prussian Blue(PB)-modified glass carbon electrode. Effects of some experimental conditions such as pH, temperature and applied potential etc. on the current response of the biosensor were investigated. The biosensor has a fast response less than 10 s and linear calibration range from 5.0×10 -6 to 2.4×10 -3 mol/L with detection limit of 1.0×10 -6 mol/L. The apparent Michaelis-Menten constant K m is found to be 3.2×10 -3 mol/L. The activation energy for enzymatic reaction is calculated to be 21.9 kJ/mol. The biosensor has a high sensitivity(420 μA·mol -1·L), long-term stability and good selectivity. This method has been used to determine the content of glucose in the real blood samples.展开更多
Collagen-glucomannan-chitosan blend films were prepared successfully by the solvent-casting method.The binding energies of C,O,N of the blend films surface,and the half-peak width,C1S energy spectra as well as the con...Collagen-glucomannan-chitosan blend films were prepared successfully by the solvent-casting method.The binding energies of C,O,N of the blend films surface,and the half-peak width,C1S energy spectra as well as the contents of C,O,N of the blend film,surface were determined by XPS.Furthmore,surface energies were calculated by the measurement of contact angle in order to further understand the surface properties of blend films This provided the theoretical basis for the application of this kind of blend film in biomedicine.展开更多
壳聚糖-果胶凝胶珠(Chitosan-pectin gel beads,CPB)吸附去除食品中重金属具有较高的潜力,为提高其稳定性、再生利用性及吸附能力,本文采用明胶(Gel)和羧甲基纤维素钠(CMC)对CPB进行改性,利用扫描电镜(SEM)、比表面积与孔隙度分析(BET)...壳聚糖-果胶凝胶珠(Chitosan-pectin gel beads,CPB)吸附去除食品中重金属具有较高的潜力,为提高其稳定性、再生利用性及吸附能力,本文采用明胶(Gel)和羧甲基纤维素钠(CMC)对CPB进行改性,利用扫描电镜(SEM)、比表面积与孔隙度分析(BET)、傅里叶变换红外光谱(FTIR)、热重分析(TG)、Zeta电位仪、X射线光电子能谱(XPS)及等技术表征其结构特性,优化吸附解析条件,并评估其对藻蓝蛋白中Pb(Ⅱ)的实际去除效果。结果显示,与CPB和Gel-CPB相比,CMC改性的CPB(CMC-CPB)热稳定性高、表面粗糙多孔、比表面积大(20.28±1.35 m^(2)/g)及Zeta电位低,对金属离子吸附能力强,且解析再生利用率高。FTIR图谱分析显示改性前后CPB官能团结构未发生明显变化,其主要结构官能团为羧基、羟基和氨基。TG分析表明改性前后的CMC-CPB的热稳定性显著高于CPB和Gel-CPB(P<0.05)。XPS光谱分析表明三种吸附剂成功吸附了Pb(Ⅱ),其中CMC-CPB对Pb(Ⅱ)的吸收峰最强。三种吸附剂(CPB、Gel-CPB和CMC-CPB)去除Pb(Ⅱ)的最佳pH和温度分别为6.0和60℃,对Pb(Ⅱ)的吸附过程均符合Langmuir吸附等温模型(R^(2)=0.9543~0.9811)和准二级动力学模型(R^(2)=0.9963~0.9991),该吸附属于单分子层化学吸附,即-COO、-OH、-CO-NH与Pb(Ⅱ)之间的络合作用。根据Langmuir模型曲线评估,CMC-CPB对Pb(Ⅱ)的最大吸附容量q_(max)为69.37 mg/g,显著高于Gel-CPB和CPB(P<0.05)。综合在藻蓝蛋白中的应用效果,CMC-CPB低成本高效安全地去除藻类和藻蓝蛋白食品中Pb(Ⅱ)具有更广阔的前景。展开更多
文摘A new type of sol-gel/organic hybrid composite film based on chitosan(CS) with methytrimethoxysilane(MTOS) was developed for the fabrication of an amperometric glucose biosensor. The hybrid composite film was used to immobilize glucose oxidase(GOD) on the surface of Prussian Blue(PB)-modified glass carbon electrode. Effects of some experimental conditions such as pH, temperature and applied potential etc. on the current response of the biosensor were investigated. The biosensor has a fast response less than 10 s and linear calibration range from 5.0×10 -6 to 2.4×10 -3 mol/L with detection limit of 1.0×10 -6 mol/L. The apparent Michaelis-Menten constant K m is found to be 3.2×10 -3 mol/L. The activation energy for enzymatic reaction is calculated to be 21.9 kJ/mol. The biosensor has a high sensitivity(420 μA·mol -1·L), long-term stability and good selectivity. This method has been used to determine the content of glucose in the real blood samples.
文摘Collagen-glucomannan-chitosan blend films were prepared successfully by the solvent-casting method.The binding energies of C,O,N of the blend films surface,and the half-peak width,C1S energy spectra as well as the contents of C,O,N of the blend film,surface were determined by XPS.Furthmore,surface energies were calculated by the measurement of contact angle in order to further understand the surface properties of blend films This provided the theoretical basis for the application of this kind of blend film in biomedicine.
文摘壳聚糖-果胶凝胶珠(Chitosan-pectin gel beads,CPB)吸附去除食品中重金属具有较高的潜力,为提高其稳定性、再生利用性及吸附能力,本文采用明胶(Gel)和羧甲基纤维素钠(CMC)对CPB进行改性,利用扫描电镜(SEM)、比表面积与孔隙度分析(BET)、傅里叶变换红外光谱(FTIR)、热重分析(TG)、Zeta电位仪、X射线光电子能谱(XPS)及等技术表征其结构特性,优化吸附解析条件,并评估其对藻蓝蛋白中Pb(Ⅱ)的实际去除效果。结果显示,与CPB和Gel-CPB相比,CMC改性的CPB(CMC-CPB)热稳定性高、表面粗糙多孔、比表面积大(20.28±1.35 m^(2)/g)及Zeta电位低,对金属离子吸附能力强,且解析再生利用率高。FTIR图谱分析显示改性前后CPB官能团结构未发生明显变化,其主要结构官能团为羧基、羟基和氨基。TG分析表明改性前后的CMC-CPB的热稳定性显著高于CPB和Gel-CPB(P<0.05)。XPS光谱分析表明三种吸附剂成功吸附了Pb(Ⅱ),其中CMC-CPB对Pb(Ⅱ)的吸收峰最强。三种吸附剂(CPB、Gel-CPB和CMC-CPB)去除Pb(Ⅱ)的最佳pH和温度分别为6.0和60℃,对Pb(Ⅱ)的吸附过程均符合Langmuir吸附等温模型(R^(2)=0.9543~0.9811)和准二级动力学模型(R^(2)=0.9963~0.9991),该吸附属于单分子层化学吸附,即-COO、-OH、-CO-NH与Pb(Ⅱ)之间的络合作用。根据Langmuir模型曲线评估,CMC-CPB对Pb(Ⅱ)的最大吸附容量q_(max)为69.37 mg/g,显著高于Gel-CPB和CPB(P<0.05)。综合在藻蓝蛋白中的应用效果,CMC-CPB低成本高效安全地去除藻类和藻蓝蛋白食品中Pb(Ⅱ)具有更广阔的前景。
