Design and Development of a Novel Glucose Biosensor Based on the Ferrocene-Functionalized Fe3O4 Nanoparticles/Carbon Nanotubes/Chitosan Nanocomposite Film Modified Electrode

采用交联法制备了羧基二茂铁功能化Fe3O4纳米粒子（FMC-AFNPs）复合材料，并将该复合纳米材料与多壁碳纳米管（MWNTs）、壳聚糖（CS）及葡萄糖氧化酶（GOD）混合修饰于自制的磁性玻碳基底(MGC)表面，制备了GOD/FMC-AFNPs/MWNTs/CS复合膜生物传感器电极. 实验结果表明，FMC-AFNPs复合材料有效地克服了二茂铁在电极表面的泄漏，且FMC-AFNPs/MWNTs/CS复合膜良好的生物兼容性较大地改善了固定化GOD的生物活性. MWNTs具有良好的导电性和大比表面积，在修饰膜内可作为电子传递“导线”，极大地促进电极的电子传递速率，提高电极的电催化活性和灵敏度. 该电极的葡萄糖检测的线性范围为1.0×10-5 ~ 6.0×10-3 molL-1，检测限为3.2×10-6 mmolL-1（S/N=3），表观米氏常数为5.03×10-3 mmolL-1，且有较好的稳定性和重现性.A novel platform for the fabrication of glucose biosensor was successfully constructed by entrapping glucose oxidase (GOD) in a ferrocene monocarboxylic acid-aminated Fe3O4 magnetic nanoparticles conjugate (FMC-AFNPs)/chitosan (CS)/multiwall carbon nanotubes (MWNTs) nanocomposite. The formation of FMC-AFNPs could effectively prevent the leakage of ferrocene and retain its electrochemical activity. This GOD/FMC-AFNPs/CS/MWNTs matrix provided a biocompatible microenvironment for retaining the native activity of the immobilized GOD. Moreover, the presence of MWNTs enhanced the charge-transport properties of the composite and facilitated electron transfer between the GOD and the electrode for the electrocatalysis of glucose. Under the optimal conditions the designed biosensor to glucose exhibited a wide and useful linear range of 1.0×10-5 to 6.0×10-3 molL-1 with a low detection limit of 3.2×10-6 molL-1（S/N=3）. The value of was 5.03×10-3 molL-1, indicating that the biosensor possesses higher biological affinity to glucose. Furthermore, the biosensor possesses satisfactory stability and good reproducibility.国家863计划资助项目(No. 2012AA022604)、国家自然科学基金（No. 20975021，No. 21275028）、福建省高校产学研科技重点项目(No. 2010Y4003)、福建省自然科学基金资助项目(No. 2010J06011)和福建医科大学博士启动基金（No. 2011BS005）资助作者联系地址：1. 福建医科大学药学院药物分析系，福建 福州 350004；2. 南昌大学高等研究院，江西 南昌 330031Author's Address: 1. Department of Pharmaceutical Analysis of the Fujian Medical University，Fuzhou 350004，China；2. Institute for Advanced Study of Nanchang University，Nanchang 330031，China通讯作者E-mail：[email protected]; [email protected]

Fabrication of Riboflavin Electrochemical Sensor Based on Au Nanoparticles/Polydopamine/Carbon Nanotubes Modified Glassy Carbon Electrode

采用原位还原法制备金纳米粒子/聚多巴胺/碳纳米管（Au-PDA-MWNTs）复合材料，并将其用于建立高灵敏检测核黄素的电化学方法.采用紫外–可见光谱、扫描电镜、x-射线能谱对Au-PDA-MWNTs复合材料进行表征，采用循环伏安法和差示脉冲伏安法探讨核黄素（RF）在Au-PDA-MWNTs修饰的玻碳电极上的电化学行为，并对RF含量进行测定.该方法对核黄素的检测在5×10-9 mol·L-1～1×10-5 mol·L-1的范围内呈良好的线性关系（R=0.9906），检测限为1.7×10-9 mol·L-1.本方法操作简便、抗干扰能力强，方法可行，因此该方法成功实现了维生素药片中RF含量的测定.A novel electrochemical platform for the high sensitivity detection of riboflavin was constructed by Au nanoparticles/polydopamine/carbon nanotubes (Au-PDA-MWCNTs) nanocomposite modified glassy carbon electrode. The Au-PDA-MWCNTs nanocomposite was synthesized by in situ reduction method. The characteristics of the as-prepared Au-PDA-MWCNTs nanocomposite modified electrodes were investigated by using UV-Vis spectroscopy, scanning electron microscopy (SEM) and electrochemical methods. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to study the electrochemical behavior of riboflavin (RF) at Au-PDA-MWCNTs nanocomposite modified electrodes. The results demonstrated that the present electrochemical sensor exhibited a wide linear range from 5×10-9 mol•L-1to 1×10-5 mol•L-1 for detection of riboflavin, with a detection limit of 1.7×10-9 mol•L-1 (S/N = 3). The present method for high sensitivity determination of riboflavin by electrochemical method at Au-PDA-MWCNTs nanocomposite modified electrodes is simple, accurate, reliable and feasible with an excellent anti-interference ability against electroactive species and metal ions. Accordingly, the present method proved to be useful for the estimation of the RF content in pharmaceutical samples with satisfactory recovery.国家863计划资助项目（2012AA022604）；国家自然科学基金（21405015,21275028）；福建省自然科学基金资助项目（2014J05092）；福建省教育厅项目（JA13147）；大学生创新创业训练计划项目基金（201410392030）作者联系地址：1. 福建医科大学药学院药物分析系, 福建 福州 350108; 2. 福建省高等学校纳米医药技术重点实验室，福建 福州 350108Author's Address: 1. Department of Pharmaceutical Analysis of the Fujian Medical University，Fuzhou 350004，China；2. The higher educational key laboratory for Nano Biomedical Technology of Fujian Province, Fujian Medical Univeristy，Fuzhou 350004，China通讯作者E-mail：[email protected]

Direct Electrochemistry of Glucose Oxidase Based on WS2 Quantum Dots and its Biosensing Application

采用水热法制备水溶性WS2量子点（WS2 QDs）材料，并将该材料进一步用于葡萄糖氧化酶（GOx）的有效固定，构建GOx/W2 QDs/GCE传感界面. 采用透射电镜、紫外-可见光谱和电化学等方法对材料的形貌、GOx的固定化过程，以及传感器的直接电化学和电催化性能进行了表征. 结果表明，WS2 QDs材料能够有效促进GOx与电极之间的直接电子转移. 并且，基于该传感器对葡萄糖良好的电催化作用，该方法有效实现了对葡萄糖的高灵敏检测，其线性范围为25 ~ 100 μmol·L-1和100 ~ 600 μmol·L-1，检测限为5.0 μmol·L-1（S/N=3）. 该传感器具有良好的选择性、重现性和稳定性，可用于实际样品血糖的分析测定.In this study, a novel electrochemical glucose biosensor has been developed by immobilizing glucose oxidase (GOx) on tungsten disulfide quantum dots (WS2 QDs) on the surface of glassy carbon electrode (GCE). Transmission electron microscopy, UV-vis spectroscopy and cyclic voltammetry were employed to characterize the morphology, structure, and electrochemical behaviors of the as-prepared WS2 QDs and the biofilm modified electrode. The results suggested that the WS2 QDs could accelerate the electron transfer between the electrode and the immobilized enzyme, which enabled the direct electrochemistry of GOx without any electron mediator. Besides, the immobilized GOx in WS2 QDsfilm exhibited excellent electrocatalytic activity toward oxidation of glucose due to the excellent biocompatibility of the WS2 QDs. The proposed GOx/WS2 QDs biofilm electrode exhibited a linear response to glucose concentration in the ranges of 25 ~ 100 μmol·L-1 and 100 ~ 600 μmol·L-1, and the detection limit of the biosensor was as low as 5.0 μmol·L-1. The biosensor also exhibited good selectivity, reproducibility and long-term stability, which might be potenially used for the detection of the real samples.国家自然科学基金项目（No.21405015, No.81400805），福建省自然科学基金资助项目（No.2014J05092, No.2016J01449），大学生创新创业训练项目基金（No.C1634）资助作者联系地址：1. 福建医科大学附属第一医院高压氧室，福建 福州 350005; 2. 福建医科大学药学院药物分析系，福建 福州 350122; 3. 福建医科大学附属第一医院内分泌科，福建 福州 350005Author's Address: 1. Department of high pressure oxygen,, The Affiliated First Hospital, Fujian Medical University, Fuzhou 350005 , China;2. Department of Pharmaceutical Analysis of the Fujian Medical University，Fuzhou 350122，China；3. Department of Endocrinology, The Affiliated First Hospital, Fujian Medical University, Fuzhou 350005 , China通讯作者E-mail：[email protected], [email protected]

Electrocatalytic Activities of Mb/AuNPs/MWNTs/GC Electrode for Hydrogen Peroxide Reduction

采用还原法制备了AuNPs/MWNTs复合材料，并构建了氧化还原蛋白质的固定化和生物传感界面AuNPs/MWNTs/GC电极. 以肌红蛋白（Myoglobin，Mb）为例，研究了固定化蛋白质在AuNPs/MWCNTs/GC电极上的直接电化学. 结果表明，AuNPs/MWCNTs复合材料不仅能有效地促进Mb与电极表面的直接电子转移，而且能很好地保持固定化Mb的生物催化活性. Mb/AuNPs/MWCNTs/GC电极对H2O2具有良好的电催化还原性能，其线性响应范围为1 ~ 138 μmol.L-1，检测下限为0.32 μmol.L-1（S/N=3），并具有较低的米氏常数（0.143 mmol.L-1）. 该电极操作简单，响应迅速，稳定性和重现性好，有望用于蛋白质的固定化及第三代生物传感器的制备.A novel matrix, multiwalled carbon nanotubes supported Au nanoparticles composite nanomaterial (AuNPs/MWNTs), for immobilization of protein and biosensing was designed using a simple and effective one-step in situ synthesis route. Using myoglobin (Mb) as a model, the direct electrochemistry of the immobilized proteins on the AuNPs/MWNTs composite was studied. The results showed that the AuNPs/MWNTs composite can maintain the bioactivity and facilitate the direct electrochemistry of Mb in the Mb/AuNPs/MWNTs/GC electrode. Based on the direct electron transfer of the immobilized Mb, the protein electrode exhibited excellent electrocatalytic activity to the reduction of H2O2 with a linear range of 1 ~ 138 μmol.L-1，low detection limit of 0.32 μmol.L-1 (S/N=3) and a low apparent Kmapp value of 0.143 mmol.L-1. The simple operation, fast response and well reproducibility of the proposed biosensor indicated its promising application in protein immobilization and preparation of the third generation biosensors.国家863计划资助项目(No. 2008AA02Z433)，国家自然科学基金资助项目(No. 20975021，No. 81171668)，福建省高校产学研科技重点项目(No. 2010Y4003)，福建省自然科学基金资助项目(No. 2010J06011)，福建医科大学校重大项目(No. 09ZD013)，福建省教育厅科技项目(No. JA10126，No. JA11110)和福建医科大学博士启动基金（No. 2011BS005）资助作者联系地址：1. 福建医科大学药学院药物分析系，福建 福州 350004； 2. 南昌大学高等研究院，江西 南昌 330031；3. 福建省药品检验所，福建 福州350001Author's Address: 1. Department of Pharmaceutical Analysis of the Fujian Medical University，Fuzhou 350004，China；2. Institute for Advanced Study of Nanchang University，Nanchang 330031，China；3. Fujian Provincial Institute for Drug Control，Fuzhou 350001，China通讯作者E-mail：[email protected]；[email protected]

Electrochemical Behaviors and Determinations of Terbutaline Sulfate at Poly Eriochrome Black T Modified Electrode

采用电化学聚合法制备了聚铬黑T膜修饰电极，应用扫描电镜、交流阻抗法和循环伏安法对修饰电极进行表征，以循环伏安法研究硫酸特布他林在修饰电极上的电化学行为，并以差示脉冲伏安法对其含量进行测定.该方法对硫酸特布他林有明显的电催化作用，在pH 7.0磷酸盐缓冲液中，氧化峰电流与硫酸特布他林浓度在1.2x10-7~2.0x10-6 mol•L-1范围内呈良好的线性关系，检测限为1.5x10-8 mol•L-1，回收率在97.9%～104.6%之间，RSD在2.8 % (C=8x10-7 mol•L-1，n=11).该方法简便灵敏，结果准确可靠，方法重复性好，可用于硫酸特布他林及其片剂的质量控制.The poly eriochrome black T modified electrode was prepared by electropolymerization. This modified electrode was characterized by scanning electron microscopy(SEM), electrochemical impedance spectroscopy(EIS) and cyclic voltammetry (CV). The electrochemical behaviors of terbutaline sulfate were studied by CV, while the recoveries were measured by differential pulse voltammetry (DPV). The modified electrode shows excellent electrocatalytic characteristics for terbutaline sulfate. In pH 7.0 phosphate buffer solution, the oxidation peak currents obtained by DPV were linear to the terbutaline sulfate concentrations over the range of 1.2x10-7~2.0x10-6 mol•L-1. The detection limit was estimated to be 1.5x10-8  mol•L-1 and the average recovery was 97.9%～104.6%. The relative standard deviation (RSD) was 2.8% for 8x10-7mol•L-1terbutaline sulfate (n=11). This method is simple, sensitive, and accurate with good repeatability, and can be used for the determination of terbutaline sulfate and the corresponding tablets.国家863计划项目（2012AA022604）；国家自然科学基金（81171668，21405015 ）；福建省教育厅科技A类项目（JA13147）；大学生创新创业训练计划项目（201410392034，201510392099）资助.作者联系地址：1. 福建医科大学药学院药物分析系, 福建 福州 350108; 2. 福建省高等学校纳米医药技术重点实验室，福建 福州 350108Author's Address: 1. Department of Pharmaceutical Analysis of Fujian Medical University，Fuzhou 350108，China; 2. The Higher Educational Key Laboratory for Nano Biomedical Technology of Fujian Province, Fujian Medical University，Fuzhou 350108，China通讯作者E-mail：[email protected]