基于石墨烯修饰碳电极的铜离子印迹电化学传感器的制备与应用

以铜离子为模板,多巴胺为功能单体,采用电聚合法在石墨烯修饰碳电极表面成功制备对铜离子有高选择性和灵敏性的印迹电化学传感器。采用差分脉冲伏安法和循环伏安法对该印迹传感器的电化学行为进行详细研究。在优化检测条件下,该印迹电化学传感器的响应电流与铜离子浓度的负对数在5.0×10~(-6)~5.0×10~(-11)mol/L浓度范围内呈良好的线性关系,最低检测限为1.0×10~(-11)mol/L。该印迹电化学传感器成功用于实际水样中的微量铜离子分析。     

米托蒽醌分子印迹传感器的研究及其应用

在弱酸性条件下, 以邻氨基酚为单体交联剂, 米托蒽醌为模板分子, 用循环伏安法电聚合成米托蒽醌分子印迹聚邻氨基酚敏感膜传感器. 该传感器对米托蒽醌具有良好的选择性和敏感度, 米托蒽醌浓度分别在3.3×10-7~1.0×10-5 mol/L及1.0×10-5~5.0×10-5 mol/L范围内与峰电流减小量呈线性关系, 检测下限为1.6×10-7 mol/L, 同时对分子印迹膜的结构和性能进行了研究.     

还原氧化石墨烯/金纳米修饰电极在新冠病毒检测中的应用

研究使用电化学沉积法在丝网印刷碳电极表面制备了还原氧化石墨烯和金纳米颗粒,构建了一种用于新冠病毒检测的石墨烯电化学传感器。通过扫描电子显微镜(SEM)和相应的电化学方法对纳米复合材料在电极表面的成功修饰进行了表征分析。并采用差分脉冲伏安法对传感器的性能进行检测,实验构建的电化学传感器具有良好的灵敏度,该传感器检线性范围为10_-10^-10_-6^mol/L,具有良好的重复性和特异性。     

基于氯化血红素复合材料的过氧亚硝酸阴离子电化学传感器的构建

构建了一种基于氯化血红素/金纳米粒子/聚三聚氰胺/多壁碳纳米管复合材料修饰玻碳电极的过氧亚硝酸阴离子电化学传感器,并成功用于过氧亚硝酸阴离子的检测.采用循环伏安法和电流-时间曲线考察了过氧亚硝酸阴离子在传感器上的电化学行为,并对传感器的制备条件及过氧亚硝酸阴离子的检测条件进行了优化.结果表明,碳纳米管滴涂量为5 μL,金沉积时间为20 s,工作电位为0.8V时,所制传感器对过氧亚硝酸阴离子的响应最大.在优化实验条件下,此传感器检测过氧亚硝酸阴离子的线性范围为1.0×10-5～3.5×10-4 mol/L和3.5×10-4～1.1×10-3 mol/L,灵敏度为0.13 A/(mol/L),检出限为1.2×10-7 mol/L(S/N=3).     

中性红掺杂SiO2纳米粒子修饰的生物传感器用于大鼠脑渗析液中L-谷氨酸的检测研究

本文以中性红为核，二氧化硅为壳，利用反相微乳液技术，通过正硅酸四乙酯的水解制备了掺杂有中性红的二氧化硅（NR@SiO₂）纳米颗粒。将NR@SiO₂纳米颗粒与_L-谷氨酸氧化酶(GluOx)混合，再通过戊二醛交联修饰于玻碳电极表面，得到以中性红为媒介体的_L-谷氨酸生物传感器。该传感器克服了传统介体型传感器中介体易流失的缺点，而且提高了检测的灵敏度。实验证明，该传感器对_L-谷氨酸的线性检测范围为5.0×10^-7~1.5×10^-4mol/L，检出限为2.0×10^-7 mol/L。与微渗析技术联用，成功地用于检测正常大鼠和患糖尿病大鼠脑中_L-谷氨酸的检测。     

二氧化锆/石墨烯复合材料对亚硝酸盐的电化学传感研究

制备了一种二氧化锆/还原氧化石墨烯(ZrO2NPs/rGO)复合材料修饰电极的亚硝酸盐电化学传感器,并成功用于亚硝酸盐的检测.采用循环伏安法和电流-时间曲线考察了修饰电极的电化学行为.实验结果表明,ZrO2NPs/rGO复合材料修饰电极对亚硝酸盐具有良好的电流响应.在最优实验条件下,电流-时间曲线中的电流响应信号与亚硝酸盐浓度在3.0×10Symbolm@@_7～1.0×10Symbolm@@_6 mol/L和1.0×10Symbolm@@_6～6.0×10Symbolm@@_6 mol/L的范围内呈良好的线性关系,检测限为1.0×10Symbolm@@_7 mol/L(S/N 3).该传感器灵敏性高、稳定性和重现性好.使用此传感器检测实际样品香肠中的亚硝酸盐的回收率为93.7％～110.4％,相对标准偏差为1.6％～2.1％.     

基于Ru(bpy)32+/AuNPs/Nafion电化学发光传感器检测已烯雌酚

利用柠檬酸钠还原氯金酸制得金纳米粒子(AuNPs),基于AuNPs/Nafion与Ru(bpy)32+之间的静电引力,制备了Ru (bpy) 32+/AuNPs/Nafion电化学发光传感器.采用循环伏安法和电化学发光法对该传感器进行了表征,结果表明该传感器具有良好的稳定性和重现性,可实现对已烯雌酚的检测.在pH=7.0的0.1 mol/L磷酸盐缓冲溶液(PBS,含0.05 mol/L三正丙胺)中,当已烯雌酚与修饰电极作用15 min时,电化学发光强度减少值与已烯雌酚浓度的负对数在1.0×10-10～5.0×10-7 mol/L范围内呈良好的线性关系,检出限为6.0 X 10-11 mol/L.对1.0×10-8 mol/L已烯雌酚平行测定11次,相对标准偏差为2.7％.测定已烯雌酚实际样品的加标回收率在98.0％～104.5％之间.     

DNA在Mg/聚2,6-吡啶二甲酸膜上的固定和杂交及其PAT基因片段的电化学阻抗谱测定

以静电吸附法使Mg²⁺修饰于玻碳电极(GCE)上电聚合的2,6-吡啶二甲酸膜(PDC)上, 制得的Mg/PDC/GCE电极, 成为DNA固定及杂交的良好平台. 应用微分脉冲伏安法和电化学阻抗谱对DNA的固定和杂交进行表征. 以电化学阻抗谱免标记法检测目标DNA比以亚甲基蓝为指示剂的微分脉冲伏安法有更高的灵敏度. 固定于电极表面的DNA探针与互补单链DNA杂交后使电负性的[Fe(CN)₆]^3-/4-的表面电子传递电阻值显著增大, 以此作为检测信号可以高灵敏度地测定目标DNA. 电化学阻抗谱检测转基因植物外源PAT基因片段, 线性范围为1.0×10^-9 ~ 1.0×10^-5 mol/L, 检测限为3.4×10^-10 mol/L.     

铜氮杂配合物修饰金电极对抗坏血酸的分析测定

本实验制备了一种新型的氮杂铜配合物修饰金电极,该电极可用于抗坏血酸的测定。采用循环伏安法和扫描电化学显微镜技术对电极进行了表征。该修饰电极可催化氧化抗坏血酸,相对于裸电极抗坏血酸在修饰电极上氧化电位移动了250mV,并且氧化电流在抗坏血酸的浓度为5.0×10−7 to 4.0×10−5 mol/L时呈线性关系,检测限为4.8×10-8 mol/L。用此方法测定抗坏血酸与文献报道的测定结果一致,这表明该电极可用作抗坏血酸测定的电化学传感器。     

自组装碳纳米管-氯洁霉素分子印迹溶胶-凝胶电化学传感器研究

结合自组装技术, 采用电聚合方法在碳纳米管修饰金电极表面制备对氯洁霉素具有特异性识别位点的分子印迹溶胶-凝胶薄膜, 成功构建了一种新型印迹溶胶-凝胶电化学传感器. 通过循环伏安法(CV)、示差脉冲法(DPV)、安培计时法(I-t)和扫描电镜(SEM)表征了该印迹溶胶-凝胶膜的电化学性能和表面形貌. 结果表明, 该传感器具有良好的选择性和灵敏度, 氯洁霉素在多壁碳纳米管修饰的印迹溶胶-凝胶传感器上的响应明显提高. 该印迹溶胶-凝胶传感器对氯洁霉素的浓度响应线性范围为5.0×10^-7~8.0×10^-5 mol/L, 检出限为2.44×10^-8 mol/L. 该传感器被成功地用于人体尿液中氯洁霉素的分析测定.     

A Polypyrrole‐Imprinted Electrochemical Sensor Based on Nano‐SnO2/Multiwalled Carbon Nanotubes Film Modified Carbon Electrode for the Determination of Oleanolic Acid

A sensitive molecularly imprinted electrochemical sensor with specific recognition ability for oleanolic acid was synthesized by modification of multiwalled carbon nanotubes (MWNTs) decorated with tin oxide nanoparticles (nano‐SnO₂/MWNTs) and polypyrrole‐imprinted polymer on a carbon electrode. The morphology and electrochemical performance of the imprinted sensor were investigated by using scanning electron microscope (SEM), X‐ray diffraction (XRD), cyclic voltammetry (CV), linear sweep voltammetry (LSV) and amperometric i–t curve. The results showed that the imprinted sensor displayed excellent selectivity toward oleanolic acid. A linear relationship between the response currents and oleanolic acid concentrations ranging from 5.0×10^?8 g/L to 2.0×10^?5 g/L was obtained for the imprinted sensor. The limit of detection (LOD) of the imprinted sensor toward oleanolic acid was calculated as 8.6×10^?9 g/L at a signal to noise ratio (S/N) of 3. This imprinted sensor was successfully applied to the determination of oleanolic acid in Acitinidia deliciosa root samples.     

Electrochemical Sensor for Sensitive Determination of Ga(III) Ion Based on β‐Cyclodextrin Incorporated Multi‐walled Carbon Nanotubes and Imprinted Sol‐gel Composite Film

A novel sensor for detection of trace gallium ion [Ga(III)] was created by stepwise modification of a gold electrode with β‐cyclodextrin (β‐CD)/multi‐walled carbon nanotubes (MWCNTs) and an ion imprinted polymer (IIP). The sensor surface morphology was characterized by scanning electron microscopy. The electrochemical performance of the imprinted sensor was investigated by cyclic voltammetry, differential pulse voltammetry and chronoamperometry. The sensor displayed excellent selectivity towards the target Ga(III) ion. Meanwhile, the introduced MWCNTs displayed noticeable catalytic activity, and β‐CD demonstrated significant enrichment capacity. A linear calibration curve was obtained covering the concentration range from 5.0×10^?8 to 1.0×10^?4 mol·L^?1, with a detection limit of 7.6×10^?9 mol·L^?1. The proposed sensor was successfully applied to detect Ga(III) in real urine samples.     

Molecularly Imprinted Poly-o-phenylenediamine Electrochemical Sensor for Entacapone

We have developed a molecularly imprinted polymer (MIP) electrochemical sensor for entacapone (ETC) based on an electropolymerised polyphenylenediamine (Po-PD) on a glassy carbon electrode (GCE) surface. The direct electropolymerisation of the o-phenylenediamine monomer (o-PD) was carried out with ETC as a template. The steps of electropolymerization process, template removal and binding of the analyte were tested by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) using [Fe(CN)₆]³⁻/[Fe(CN)₆]^{4 −} as a redox probe. The operation of the sensor has been investigated by differential pulse voltammetry (DPV). Under optimal experimental conditions, the response of the DPV was linearly proportional to the ETC concentration between 1.0×10⁻⁷ and 5.0×10⁻⁶ M ETC with a limit of detection (LOD) of 5.0×10⁻⁸ M. The developed sensor had excellent selectivity without detectable cross-reactivity for levodopa and carbidopa. The MIP sensor was successfully used to detect ETC in spiked human serum samples.     

利巴韦林原位聚合分子印迹电化学传感器的研制

利用原位聚合分子印迹技术,以3-氨基苯硼酸(3-ABBA)为功能单体,利巴韦林(RIB)为目标分子,以硼酸和顺式二醇在不同酸碱度条件下可逆形成环内酯键为原理,在玻碳电极表面原位聚合形成利巴韦林分子印迹膜,研制了测定利巴韦林的分子印迹电化学传感器。采用循环伏安法(CV)和差分脉冲法(DPV)对印迹膜性能进行研究。DPV测试表明:在最优实验条件下,利巴韦林的浓度在5.0×10~(-8)~1.0×10~(-5)mol/L范围内与峰电流呈良好的线性关系,相关系数(r~2)为0.995 3,检出限(S/N=3)为1.5×10~(-8)mol/L。特异性实验表明制备的传感器对利巴韦林的选择性良好。该分子印迹电化学传感器可用于食品中利巴韦林的检测。     

Preparation of Molecularly Imprinted Electrochemical Sensor for Detection of Vincristine Based on Reduced Graphene Oxide/Gold Nanoparticle Composite Film

An innovative molecularly imprinted electrochemical sensor was fabricated based on reduced graphene oxide (RGO) and gold nanocomposite (Au) for rapid detection of vincristine (VCR). The RGO‐Au composite membrane was obtained via direct one‐step electrodeposition technique of graphene oxide (GO) and chloroauric acid (HAuCl₄) on the surface of a glassy carbon electrode (GCE) by means of cyclic voltammetry (CV) in the potential range between ?1.5 and 0.6 V in phosphate buffer solution (PBS) of pH 9.18, which is capable of effectively utilizing its superior electrical conductivity, larger specific surface area due to its synergistic effect between RGO and Au. The molecularly imprinted polymers (MIPs) were synthesized on the RGO‐Au modified glassy carbon electrode surface with VCR as the template molecular, methyl acrylic acid (MAA) as the functional monomer, and ethylene glycol maleic rosinate acrylate (EGMRA) as a cross‐linker. The performance of the sensor was investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) in detail. Under the optimum conditions, the fabricated sensor exhibited a linear relationship between oxidation peak current and VCR concentration over the range of 5.0×10^?8–5.0×10^?6 mol·L ^minus;1 with a correlation coefficient of 0.9952 and a detection limit (S/N=3) of 2.6×10^minus;8 mol·L^minus;1. The results indicated that the imprinted polymer films exhibited an excellent selectivity for VCR. The imprinted sensor was successfully used to determine VCR in real samples with recoveries of 90% –120% by using the standard addition method.     

Development of an Electrochemical Sensor for Selective Determination of Dopamine Based on Molecularly Imprinted Poly(p-aminothiophenol) Polymeric Film

In this study, a molecularly imprinted electrochemical sensor (MIP/DA) was investigated for selective and sensitive determination of dopamine (DA) by electrochemical polymerization of p-aminothiophenol in the presence of DA on gold electrode. According to electrochemical behaviour of the sensor, gained through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), MIP/DA sensor showed distinctive electron transfer characteristics in comparison to the non-imprinted (NIP/DA) sensor. Besides the MIP/DA sensor showed high selectivity for dopamine through its analyte specific cavities. The sensor had a broad working range of 5.0×10⁻⁸–2.0×10⁻⁷ M with a limit of detection (LOD) of 1.8×10⁻⁸ M and the developed sensor was successfully applied for determination of dopamine in pharmaceutical samples.     

A Novel Electrochemical Sensor Based on Copper‐based Metal‐Organic Framework for the Determination of Dopamine

A glassy carbon electrode (GCE) modified with a copper‐based metal‐organic framework (MOF) [HKUST‐1, HKUST‐1 = Cu₃(BTC)₂ (BTC = 1,3,5‐benzenetricarboxylicacid)] was developed as a highly sensitive and simple electrochemical sensor for the determination of dopamine (DA). The MOF was prepared by a hydrothermal process, and the morphology and crystal phase of the MOF were characterized by scanning electron microscopy (SEM) and X‐ray diffraction (XRD), respectively. Meanwhile, the electrochemical performance was investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). Under optimized conditions, the modified electrode showed excellent electrocatalytic activity and high selectivity toward DA. The linear response range was from 5.0 × 10⁻⁷ to 1.0 × 10⁻⁴ M and the detection limit was as low as 1.5 × 10⁻⁷ M. Moreover, the electrochemical sensor was used to detect DA in real samples with excellent results. MOF‐based sensors hold great promise for routine sensing applications in the field of electrochemical sensing.     

钯纳米粒子修饰的三甲氧苄啶分子印迹膜传感器的制备及其识别性能研究

采用N,N′-亚甲基双丙烯酰胺(MBA)为功能单体、钯纳米粒子为掺杂剂、马来松香丙烯酸乙二醇酯为交联剂,在玻碳电极上热聚合具有三甲氧苄啶(TMP)识别性能的钯纳米材料修饰的分子印迹传感膜.采用扫描电镜及红外光谱对合成的钯纳米材料、印迹传感膜的形貌及其结构进行了表征;采用循环伏安法(CV)、交流阻抗法(EIS)对钯纳米粒子掺杂的印迹电极与无掺杂电极的电化学性能进行了研究.结果表明,纳米粒子掺杂的印迹电极与无掺杂电极的表面形貌及电化学性能明显不同.差分脉冲伏安法(DPV)表征结果表明,TMP的浓度在5.0×10-7~4.0 ×10-3 mol/L范围内与脉冲峰电流呈良好的线性关系(R=0.9995),检出限为3.2×10-8 mol/L (S/N=3).此钯纳米粒子掺杂的印迹传感器具有较高的灵敏度.即时电流测定结果表明,新诺明(SMZ)、磺胺嘧啶(SDZ)、葡萄糖 (Glu)、尿素 (Urea)对三甲氧苄啶(TMP)的测定不产生干扰.将此印迹传感器用于实际样品中TMP的检测,加标回收率为96.8%~102.0%.     

Electrochemical sensor for determination of aflatoxin B1 based on multiwalled carbon nanotubes-supported Au/Pt bimetallic nanoparticles

A sensitive and selective imprinted electrochemical sensor for the determination of aflatoxin B₁ (AFB₁) was constructed on a glassy carbon electrode by stepwise modification of functional multiwalled carbon nanotubes (MCNTs), Au/Pt bimetallic nanoparticles (Au/PtNPs), and a thin imprinted film. The fabrication of a homogeneous porous poly o-phenylenediamine (POPD)-grafted Au/Pt bimetallic multiwalled carbon nanotubes nanocomposite film was conducted by controllable electrodepositing technology. The sensitivity of the sensor was improved greatly because of the nanocomposite functional layer; the proposed sensor exhibited excellent selectivity toward AFB₁ owing to the porous molecular imprinted polymer (MIP) film. The surface morphologies of the modified electrodes were characterized using a scanning electron microscope. The performance of the imprinted sensor was investigated by cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy in detail. A linear relationship between the sensor response signal and the logarithm of AFB₁ concentrations ranging from 1?×?10^?10 to 1?×?10^?5 mol L^?1 was obtained with a detection limit of 0.03 nmol L^?1. It was applied to detect AFB₁ in hogwash oil successfully.     

Selective and sensitive molecularly imprinted sol–gel film-based electrochemical sensor combining mercaptoacetic acid-modified PbS nanoparticles with Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>@Au–multi-walled carbon nanotubes–chitosan

A sensitive molecularly imprinted electrochemical sensor was developed for selective detection of streptomycin by combination of mercaptoacetic acid-modified PbS nanoparticles with Au-coated Fe₃O₄ magnetic nanoparticles dispersed multi-walled carbon nanotubes doped chitosan film. The imprinted sensor was fabricated onto the Au electrode via stepwise modification of nanocomposites and an electrodeposited thin film of molecularly imprinted polymers via sol–gel technology. The morphologies and electrochemical behaviors of the imprinted sensor were characterized by scanning electron microscope, cyclic voltammetry, and differential pulse voltammetry, respectively. The prepared sensor showed very high recognition ability and selectivity for streptomycin. Under optimal conditions, the imprinted sensor displayed good electrocatalytic activity to the redox of streptomycin. And the differential voltammetric anodic peak current was linear to the logarithm of streptomycin concentration in the range from 1.0 × 10⁻⁶ to 1.0 × 10⁻³ mol L⁻¹, and the detection limit obtained was 1.5 × 10⁻⁹ mol L⁻¹. This proposed imprinted sensor was used successfully for streptomycin determination in different injection solution samples.