纳米氧化铜修饰的苯巴比妥分子印迹传感器的制备及其电化学性能

为了改善分子印迹传感器的灵敏度,在四丁基高氯酸铵的支持电解质溶液中,以甲基丙烯酸为功能单体,马来松香丙烯酸乙二醇酯为交联剂在纳米氧化铜修饰过的玻碳电极上电聚合了一种苯巴比妥(PB)识别性能的分子印迹传感膜.采用循环伏安(CV)法、差分脉冲伏安(DPV)法及交流阻抗(EIS)法对这种纳米氧化铜修饰过的印迹及非印迹电极的电化学性能进行了研究,结果显示纳米氧化铜修饰过的印迹及非印迹电极的电化学性能完全不同.X射线衍射(XRD)证实纳米粒子为氧化铜.采用扫描电镜(SEM)对纳米氧化铜修饰过的印迹传感器的形貌进行分析,发现纳米氧化铜分散在电极表面,改善了修饰印迹传感器的识别点.差分脉冲伏安法(DPV)表明苯巴比妥的浓度在1.0×10-8-1.8×10-4mol·L-1范围内呈现良好的线性关系(线性相关系数R=0.9994);检出限2.3×10-9mol·L-1(信噪比(S/N)=3).研究结果表明纳米氧化铜修饰过的印迹传感器具有较高灵敏度及选择性.此印迹传感器能用于实际样品中苯巴比妥的检测,加标回收率在95.0%-102.5%.     

纳米氧化铜修饰的苯巴比妥分子印迹传感器的制备及其电化学性能

为了改善分子印迹传感器的灵敏度, 在四丁基高氯酸铵的支持电解质溶液中, 以甲基丙烯酸为功能单体, 马来松香丙烯酸乙二醇酯为交联剂在纳米氧化铜修饰过的玻碳电极上电聚合了一种苯巴比妥(PB)识别性能的分子印迹传感膜. 采用循环伏安(CV)法、差分脉冲伏安(DPV)法及交流阻抗(EIS)法对这种纳米氧化铜修饰过的印迹及非印迹电极的电化学性能进行了研究, 结果显示纳米氧化铜修饰过的印迹及非印迹电极的电化学性能完全不同. X射线衍射(XRD)证实纳米粒子为氧化铜. 采用扫描电镜(SEM)对纳米氧化铜修饰过的印迹传感器的形貌进行分析, 发现纳米氧化铜分散在电极表面, 改善了修饰印迹传感器的识别点. 差分脉冲伏安法(DPV)表明苯巴比妥的浓度在1.0×10^-8-1.8×10^-4 mol·L^-1 范围内呈现良好的线性关系(线性相关系数R=0.9994); 检出限2.3×10^-9 mol·L^-1 (信噪比(S/N)=3). 研究结果表明纳米氧化铜修饰过的印迹传感器具有较高灵敏度及选择性. 此印迹传感器能用于实际样品中苯巴比妥的检测, 加标回收率在95.0%-102.5%.     

基于纳米银/碳纳米纤维复合材料的增强效应电化学测定多贝斯

将银纳米粒子(AgNPs)电沉积在碳纳米纤维(CNFs)修饰玻碳电极表面制备纳米银/碳纳米纤维修饰玻碳电极(AgNPs/CNFs/GCE).采用扫描电镜考察其表面形态,在K3[Fe(CN)6]-K4[Fe(CN)6]体系中用循环伏安法和电化学阻抗法研究AgNPs/CNFs/GCE的电化学行为.采用循环伏安法和方波伏安法...     

铂-钯纳米簇/石墨烯修饰电极的制备及其在氯霉素传感中的应用

通过电沉积法制备了铂-钯纳米簇/石墨烯修饰电极(Pt-Pd/RGO/GCE).利用扫描电子显微镜(SEM)和X射线能量色散光谱(EDS)对铂-钯纳米簇/石墨烯修饰电极进行了表征;采用循环伏安法(CV)对修饰电极电化学性质进行了研究,探究了铂钯原子比例和电沉积圈数对制备修饰电极的影响,研究了修饰电极对氯霉素(CAP)电催...     

三维纳米枝状物表面制备蛋白质印迹聚合物及其性能

在金电极表面制备了3D金/铜纳米枝状物,并以丙烯酰胺为功能单体,N,N-亚甲基双丙烯酰胺为交联剂,血红蛋白为模板分子,在枝状物表面成功制备了蛋白质印迹聚合物。利用循环伏安法和扫描电子显微镜对制备的聚合物修饰电极进行了表征,通过微分脉冲伏安法、利用制备的聚合物修饰电极可对溶液中的血红蛋白进行检测,得到比已报道的类似印迹传感器更宽的检测范围和更低的检测下限,其线性范围为1.0×10~(-14)~1.0×10~(-1)mg/L,检测限为1.9×10~(-15)mg/L(S/N=3),相关系数为0.9975。实验结果表明,在电极表面制备的金/铜纳米枝状物,大大提高了电极的电子传递能力,也提高了印迹聚合物修饰电极的检测范围。     

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%.     

TiO2/HAP/MWCNT纳米复合薄膜修饰电极伏安法测定工业废水中邻苯二胺

利用壳聚糖溶液分散纳米二氧化钛(TiO2),纳米羟基磷灰石(HAP)和多壁碳纳米管(MWCNT)制备了新型纳米复合薄膜修饰电极.基于此电极建立了一种无汞、高灵敏度测定痕量邻苯二胺(o-PDA)的方法.采用扫描电镜(SCE)、循环伏安(CV)和交流阻抗(EIS)等方法对修饰电极进行了表征；并研究了o-PDA在修饰电极上的...     

基于立方体纳米氧化亚铜修饰的安培型葡萄糖生物传感器的制备及性能研究

将合成的立方体纳米氧化亚铜用于修饰玻碳电极,在其上固定葡萄糖氧化酶,构建了高灵敏的安培型葡萄糖生物传感器.采用X射线衍射(X RD)、扫描电镜(SEM)对合成的立方体纳米氧化亚铜及其修饰电极进行了表征.结果表明,合成的纳米氧化亚铜为均匀的立方体形状.采用循环伏安法(CV)、交流阻抗谱(EIS)、差分脉冲伏安法(DPV)及计时电流法(CA)考察了修饰电极的电化学行为.在含0.1 mmol/L葡萄糖的磷酸盐缓冲溶液(pH 7.4)中研究了立方体纳米氧化亚铜修饰电极的循环伏安(CV)响应,实验结果表明,此修饰电极对葡萄糖显示出良好的电催化性能.DPV响应电流与葡萄糖的浓度在5.0×10-6 ～4.0× 10-3mol/L范围内呈良好的线性关系,线性相关系数R2=0.9983,检出限为6.8×10-7 mol/L(S/N=3).CA实验结果表明,尿酸、抗坏血酸、D-果糖对传感器不产生干扰.本传感器具有较好的重现性和稳定性,可用于实际样品中葡萄糖的检测.     

氧化锌纳米簇-金纳米颗粒-壳聚糖复合膜修饰电极用于示差脉冲伏安法测定吗啡

将制备的氧化锌纳米簇和金纳米颗粒分散在壳聚糖中并滴涂在玻碳电极表面,制备了氧化锌纳米簇-金纳米颗粒-壳聚糖复合膜修饰电极(Au-ZnO-CHIT/GCE)。采用循环伏安法研究了吗啡在修饰电极上的电化学行为。结果表明:吗啡在该修饰电极上出现了一个氧化峰,提出了用示差脉冲伏安法测定吗啡的方法。吗啡浓度在5.3×10-6~6.5×10-4mol.L-1范围内与氧化峰电流呈线性关系,检出限(3S/N)为1.8×10-6mol.L-1。修饰电极用于尿液中吗啡的测定,回收率在80.0%~99.6%之间。     

碳纤维微电极负载金纳米粒子用于绿茶中儿茶素的检测

本文开发了基于纳米金修饰的碳纤维超微电极(CFME)用于儿茶素的定量检测。通过使用柠檬酸三钠还原氯金酸制得纳米金粒子(AuNPs),采用恒电位电沉积法将纳米金修饰在CFME表面。在pH 2.00的Tris-HCl缓冲溶液中,采用差分脉冲法和循环伏安法考察了修饰前后电极对儿茶素的电催化性能。结果表明,纳米金修饰电极对儿茶素具有明显的电催化效果。在优化实验条件下,纳米金修饰的碳纤维超微电极(AuNPs/CFME)与儿茶素浓度在1.00×10^-3~10.0μmol/L范围内呈良好的线性关系,且AuNPs/CFME的电化学性能非常稳定,具有良好的重现性。该方法操作简单,准确性高,可用于对儿茶素进行定量检测。     

新型多壁碳纳米管/白藜芦醇印迹溶胶-凝胶层层组装电化学传感器研究

采用电化学沉积方法将印迹溶胶-凝胶膜沉积到功能化碳纳米管(MWNT-COOH)修饰的碳电极表面,成功研制一种新型多壁碳纳米管/白藜芦醇印迹溶胶-凝胶电化学传感器.采用扫描电镜(SEM),循环伏安法(CV),方波伏安法(SWV)和计时电流法(i-t)详细考察该印迹溶胶-凝胶膜的形态和电化学性能.结果表明该传感器对白藜芦醇具有较高的选择性和亲和性.与无多壁碳纳米管修饰的印迹传感器比较,MWNT层修饰的印迹传感器电流响应信号明显提高.白藜芦醇与印迹溶胶-凝胶膜的特异性结合使该传感器的电流发生变化,电流变化与白藜芦醇浓度在5.0×10-7～8.0×10-5mol?L-1范围内呈良好线性关系,检测限为5.1×10-8mol?L-1,该传感器成功应用于葡萄酒中白藜芦醇含量的检测.     

新型乙基溴硫磷印迹膜/纳米金化学修饰电极的研制及应用

以恒电位将金纳米粒子(AuNP)沉积于玻碳电极表面,在模板分子乙基溴硫磷存在下通过循环伏安法将L-半胱氨酸组装到金纳米粒子修饰的玻碳电极上,制备了可选择性识别乙基溴硫磷的L-Cys/ AuNP/ GCE印迹膜电极.结果表明,该电极具有良好的稳定性和重现性,对乙基溴硫磷的线性响应范围为2.5 ～17.5μmol/L,检出...     

盐酸普萘洛尔分子印迹电化学传感器的制备与研究

以盐酸普萘洛尔为目标模板分子,通过电聚合多巴胺,在多壁碳纳米管修饰的玻碳电极表面制备了对目标分子有特异响应的分子印迹电化学传感器.利用扫描电子显微镜、循环伏安法和差示脉冲伏安法对此传感器的表面形貌及性能进行了表征,并且优化了检测条件,研究了印迹传感器对模板分子及其结构类似物的选择性响应.结果表明:此传感器具有较好的选择性响应,而且碳纳米管的存在显著提高了传感器的灵敏度.盐酸普萘洛尔的浓度在0.20～100 μmol/L范围内与峰电流呈良好的线性关系;检出限为2.53×10-8 mol/L(S/N=3).此传感器还具有良好的稳定性和重现性.     

磁性石墨烯修饰辛基酚印迹传感器制备及应用研究

以辛基酚(4-OP)为模板分子,多巴胺为功能单体,采用电聚合技术在磁性石墨烯修饰碳电极表面制备对辛基酚具有高选择性与灵敏性的印迹电化学传感器。采用循环伏安法(CV)和差分脉冲伏安法(DPV)对此印迹传感器的电化学性能进行详细表征;采用扫描电子显微技术对修饰电极的形貌进行表征。结果表明,此印迹电化学传感器对辛基酚具有良好的特异识别性能。采用 DPV 法考察了孵化时间和洗脱溶剂对印迹传感器性能影响,结果表明,最佳孵化时间为14 min。此印迹电化学传感器的响应电流(△IR )与辛基酚在5.0×10-6~5.0×10-9 mol/ L 范围内浓度的负对数(-lgC)呈良好的线性关系,线性方程为△IR ( mA)=-0.25lgC(mol/ L)+2.35,检出限为3.64×10-10 mol/ L (S/ N=3)。此印迹电化学传感器对辛基酚具有良好的选择性和灵敏性,成功用于实际水样中辛基酚的检测,回收率为96.0%~104.0%。     

Molecularly Imprinted Polypyrrole for DNA Determination

In this study graphite electrodes modified by a thin DNA‐imprinted polypyrrole layer, which was able to bind specific target‐DNA, are reported. For this aim, electrochemical synthesis of polypyrrole was performed on a pencil graphite electrode by cyclic voltammetry (CV) or by potential pulse sequences (PPS). The modified electrode surface was used for electrochemical determination of target‐DNA by differential pulse voltammetry. According to our best knowledge this is a first report on the application of DNA‐imprinted polymer for the determination of target‐DNA. The results showed that the molecularly imprinted polypyrrole (MIPPy) layer that formed on the carbon electrode surface was sensitive for target‐DNA, while the nonimprinted polypyrrole layer was not sensitive to the same target‐DNA. Comparison of electrodes modified using PPS and CV techniques is presented.     

A Novel DNA Probe Based on Molecularly Imprinted Polymer Modified Electrode for the Electrochemical Monitoring of DNA

A DNA probe that was based on methylene blue (MB) imprinted polyvinyl pyridine polymer (MIP) modified carbon paste electrodes were developed for the first time for electrochemical monitoring of DNA. Probes were built up by adsorbing MB onto modified electrodes prior to DNA immobilization. It was shown that DNA strongly immobilizes on MIP modified electrodes when MB was adsorbed in advance of DNA immobilization. The performance of the MB imprinted polymer modified carbon paste electrodes (MIP‐CPE) to rebind the template molecule (MB) were compared to those of control polymer modified (non‐imprinted polymer NIP‐CPE) and bare (CPE) electrodes. Electrochemical signal resulting from the oxidation of guanine moiety of the immobilized probe DNA was high enough on the constructed platform, implicating that probes of this kind could be favorably used for DNA analysis. These probes exhibited high selectivity for its complementary DNA sequences (target). HBV‐DNA hybridization was studied to evaluate the selectivity of the probes for complementary, non‐complementary and mismatch sequences. The detection limit of the probe for the target DNA was 8.72 µg/mL (1.38 µM), which was better than those attained by some earlier DNA sensor studies.     

Determination of Oxytetracycline with a Gold Electrode Modified by Chitosan-Multiwalled Carbon Nanotube Multilayer Films and Gold Nanoparticles

A molecularly imprinted electrochemical sensor was fabricated based on a gold electrode modified by chitosan-multiwalled carbon nanotube composite (CS-MWCNTs) multilayer films and gold nanoparticles (AuNPs) for convenient and sensitive determination of oxytetracycline (OTC). The multilayer of CS-MWCNTs composites and AuNPs were used to augment electronic transmission and sensitivity. The molecularly imprinted polymers (MIPs) were synthesized using OTC as the template molecule and o-phenylenediamine (OPD) as the functional monomer. They were modified on a gold electrode by electropolymerization. The electrochemical behavior of OTC at the imprinted sensor was characterized by cyclic voltammetry (CV), scanning electron microscopy (SEM), and amperometry. The molecularly imprinted sensor showed high selectivity and excellent stability toward OTC. The linear range was from 3.0 × 10^?8 to 8.0 × 10^?5 mol/L, with a limit of detection (LOD) of 2.7 × 10^?8 mol/L (S/N = 3). The developed sensor showed good recovery in spiked samples analysis.     

Selective Electrochemical Determination of Salicylic Acid in Wheat Using Molecular Imprinted Polymers

Salicylic acid is a phytohormone, playing crucial roles in signal transduction, crop growth, and development, and defense to environmental challenges. In this study, a highly selective electrochemical sensor was designed and used to determine salicylic acid using molecularly imprinted polymers for recognition. The electrochemical sensor was fabricated via stepwise modification of gold nanoparticle–graphene–chitosan and molecularly imprinted polymers on a glassy carbon electrode. With electrochemical deposition, a gold nanoparticle–graphene–chitosan film was deposited on the glassy carbon electrode and enhanced the sensitivity. Molecularly imprinted polymers with adsorbed template salicylic acid were added to the surface of the modified electrode. Cyclic voltammetry and electrochemical impedance spectroscopy were used to characterize the modified electrodes. Salicylic acid in wheat was quantified by the sensor using the molecularly imprinted polymer/gold nanoparticle–graphene–chitosan/glassy carbon electrode. Concentrations of salicylic acid from 5?×?10^?10 to 5?×?10^?5?mol?L^?1 were determined showing that the developed sensor was suitable for the analysis of food.     

碳纳米管修饰电极分子印迹传感器快速测定沙丁胺醇

以单壁碳纳米管(SWNTs)为电极材料,应用分子印迹技术,以邻苯二胺为功能单体、沙丁胺醇为模板,采用电化学聚合法制备了一种新型的快速检测沙丁胺醇分子印迹传感器,并运用电化学方法去除模板.在磷酸盐缓冲溶液(PBS)中,利用线性溶出伏安法对印迹和非印迹膜的性能进行了比较,对分子印迹膜的影响因素进行了优化.实验表明,本传感器...     

分子印迹电化学传感器检测水杨酸

以水杨酸(SA)为模板分子,邻苯二胺(o-PPD)及吡咯(Py)为复合功能单体,在石墨烯修饰的玻碳电极表面制备分子印迹电化学传感器(MIP/GO/GCE),用扫描电镜(SEM)观察印迹膜的表面形貌,方波伏安法(SWV)和循环伏安法(CV)对分子印迹传感器的性能进行表征。通过优化实验条件,显示SA浓度在1.0×10-8~1.0×10-2 mol/L范围内,分子印迹传感器峰电流与SA浓度负对数具有良好的线性关系,检出限为8.6×10-9 mol/L。该传感器对SA具有良好的选择性,样品回收率为101%~106%,相对标准偏差(RSD)为3.8%。SA分子印迹传感器的制备简单、抗干扰性好、灵敏度高、成本低廉,具有较好实用价值。