多壁碳纳米管固相萃取技术的应用

多壁碳纳米管是一种新型纳米材料,具有独特的管状结构、良好的化学稳定性、热稳定性和高比表面积,是一种优秀的吸附材料。本文综述了多壁碳纳米管的合成,多壁碳纳米管固相萃取技术在农药残留、金属离子、多环芳烃化合物等分离富集方面的应用,以期为多壁碳纳米管固相萃取技术的进一步拓展应用提供参考。      

多壁纳米碳管电极电化学行为的研究

研究了多壁纳米碳管(MWNTs)在碱性电解液中的电化学行为.结果表明:电极集流体结构对其电化学活性有较大影响;循环伏安曲线显示,氢在MWNTs上的电化学反应可逆性随循环次数增加而有一定改善;阴极极化曲线表明了MWNTs不同类型上的氢析出电位有一定差别.认为MWNTs在碱性电解液中氢的电化学反应可逆,氢析出电位与MWNTs类型有关.     

Sensitive electrochemical determination of luteolin in peanut hulls using multi-walled carbon nanotubes modified electrode

A simple and highly sensitive electrochemical method was developed for the determination of trace-level luteolin, based on the multi-walled carbon nanotubes (MWNTs) modified glassy carbon electrode (GCE). The electrochemical behaviours of luteolin indicate that MWNTs modified glassy carbon electrode (MWNTs/GCE) can greatly enhance the electrocatalytic activity towards the redox of luteolin. It leads to a considerable improvement of the redox peak current for luteolin and allows the development of a highly sensitive voltammetric sensor for the determination of luteolin. A series of experimental parameters including the pH of supporting electrolyte, accumulation potential and time were optimised. The results showed that the oxidative peak currents increased linearly with the concentration of luteolin in the range of 2.0 × 10⁻¹⁰ to 3.0 × 10⁻⁹ M, with a detection limit of 6.0 × 10⁻¹¹ M (S/N = 3). The analytical performance of this sensor has been evaluated for detection of luteolin in peanut hulls as a real sample.     

多壁碳纳米管QuEChERS-液相色谱-串联质谱法快速检测茶叶中氯虫苯甲酰胺残留量

目的 建立多壁碳纳米管QuEChERS-高效液相色谱-串联质谱法测定茶叶中氯虫苯甲酰胺残留量的分析方法。方法 样品经乙腈提取,多壁碳纳米管QuEChERS方法净化,经Agilent Eclipse Pluse C₁₈色谱柱( 2.1 mm× 50 mm,1.8 μm),以0.1%甲酸水(A)-乙腈(B)为流动相进行梯度分离,并在串联质谱正离子多反应监测模式(MRM)下进行测定,空白基质配标外标法定量。结果 5种茶叶中氯虫苯甲酰胺在0.100～50.0 ng/mL的范围内线性良好(r＞0.995),检出限为0.50 μg/kg, 定量限为1.2μg/kg, 在0.500、5.00、500 μg/kg添加水平下, 平均加标回收率在84.4%~103.9%之间, 相对标准偏差为0.8%~8.3% (n=6)。结论：该方法具有较高的灵敏度,操作简便,测定结果准确可靠,可用于茶叶中氯虫苯甲酰胺农药残留量的检测。     

多壁碳纳米管固相萃取净化-气相色谱质谱联用 同时测定茶叶中26种农药

目的建立一种多壁碳纳米管固相萃取净化-气相色谱质谱联用同时测定茶叶中26种农药的检测方法。方法样品经乙腈提取,过滤型多壁碳纳米管柱净化后,使用气相色谱质谱仪检测。结果碳纳米管净化能够有效去除茶叶中干扰物质,简化实验步骤,降低前处理过程中农药的分解。26种农药在0.04~1.6μg/m L范围内具有较好的线性。方法的检出限为0.005~0.05 mg/kg,定量下限为0.015~0.15 mg/kg。采用该方法对茶叶样品进行加标回收率实验,加标回收率在66.6%~125.5%,相对标准偏差为0.3%~6.4%(n=5)。结论该方法快速、准确、灵敏,适合茶叶中多种农药的同时测定。     

基于多壁碳纳米管修饰四氧化三钴传感器检测白菜中杀螟硫磷

目的 基于多壁碳纳米管修饰四氧化三钴(Co3O4@MWCNTs)纳米复合物,成功构建了一种用于白菜样品中快速检测杀螟硫磷的电化学传感器。方法 将以醋酸钴水合物为钴源,而采用简便水热法制备的四氧化三钴纳米颗粒与多壁碳纳米管复合成Co3O4@MWCNTs纳米材料,以Co3O4@MWCNTs纳米复合物修饰的玻碳电极(GCE)为工作电极,利用循环伏安法(CV)研究了杀螟硫磷在修饰电极界面的电化学行为;并通过逐步优化支持电解质的PH值、复合材料质量比等检测条件。结果 实验结果表明,Co3O4@MWCNTs/GCE改性电极能够实现对杀螟硫磷的灵敏检测。在最优条件下,该传感器的线性浓度范围为1.0×10-5~1.4×10-4 mol/L,R2=0.991,检出限为7.8×10-8 mol/L(S/N=3);并成功用于实际白菜样品中杀螟硫磷的加标回收实验,回收率为93.7%~97.6%。结论 Co3O4和MWCNTs复合后制备的传感器不仅可以选择性识别杀螟硫磷,达到快速检测目标物的需求。而且,其电化学性能也得到了明显的提升,展现出较高的灵敏度,表明该传感器在现场检测中具有非常大的应用潜力。     

碳纳米管及其复合材料的制备与性能研究进展

介绍了碳纳米管的制备、纯化和功能化修饰方法,碳纳米管/聚合物复合材料的制备主要有溶液共混法、固相加热共融法和原位聚合法,以及复合材料的力学性能、导电性能和光电性能,指出碳纳米管与聚合物的详细复合机理尚待重点研究.     

多壁碳纳米管固相萃取/气相色谱-质谱测定蔬菜中的苯醚甲环唑农药残留

以多壁碳纳米管(MWCNTs)为固相萃取材料,建立了蔬菜中苯醚甲环唑农药残留的气相色谱-质谱联用(GC-MS)分析方法。样品经乙酸乙酯匀浆提取后,以MWCNTs固相萃取柱净化,用GC-MS进行检测。研究了不同提取溶剂和MWCNTs的量对提取净化效率的影响。结果表明:在最优实验条件下,苯醚甲环唑在0.005~2.0 μg/mL范围内呈良好的线性关系,相关系数为0.9997,检出限为0.001 mg/kg,空白蔬菜样品在0.01、0.10、1.00 μg/mL 3个加标水平下的回收率在84.2%~111.3%之间,相对标准偏差(n=5)为5.3%~11.9%。该方法灵敏度高,选择性好,抗干扰能力强,适合蔬菜中苯醚甲环唑残留量的定性确证分析和定量分析。     

Enhancing the flame retardant of polyethylene terephthalate (PET) fiber via incorporation of multi-walled carbon nanotubes based phosphorylated chitosan

Phosphorylated chitosan (PCS) were first deposited on the multi-walled carbon nanotubes (MWNTs) surface via chemical modification to obtain functionalized MWNTs-based PCS (PCS-MWNTs). Then, a series of PET fibers with MWNTs or PCS-MWNTs were prepared via melt spinning. The microstructure and molecular structure of PCS-MWNTs were characterized by field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy. The morphological structures, mechanical, thermal, and flame-retardant properties of the PET fibers containing MWNTs or PCS-MWNTs were analyzed by FESEM, therogravimetry, differential scanning calorimetry, cone and electronic tension meter method. The results showed that MWNTs were coated with PCS. Compared to PET fiber, when the content of PCS-MWNTs was 0.9 wt.%, the PCS-MWNTs/PET fibers exhibited an efficient flame-retardant capacity, with the lower heat release rate and total release rate values of 81.03 kW/m² and 39.05 MJ/m², respectively, decreasing by 130.06 kW/m² and 11.87 MJ/m². The thermal stability of PCS-MWNTs/PET fibers strengthened, and the char residue increased from 7.21 to 13.52%. Compared to MWNTs/PET fiber, the crystallization property and tensile strength of PCS-MWNTs/PET fiber improved, because of the good dispersion and strong interface binding force with the PET fiber. Overall, the PCS layer endowed the MWNTs with good dispersion and flame-retardant characteristics.     

Rapid analysis of phthalates in beverage and alcoholic samples by multi-walled carbon nanotubes/silica reinforced hollow fibre-solid phase microextraction

A novel procedure based on multi-walled carbon nanotubes (MWCNTs)/silica reinforced hollow fibre solid-phase microextraction combined with gas chromatography–mass spectrometry has been developed to analyse trace phthalate acid esters in beverage and alcoholic samples. Because of their excellent adsorption capability towards hydrophobic compounds, functionalized MWCNTs, acting as solid-phase sorbent, were co-deposited with silica particles in the pores of polypropylene hollow fibre through a layer-by-layer self-assembly technique. The parameters influencing the extraction efficiency, such as pH values and ionic strength of sample solution, extraction time, temperature and desorption solvent were optimised. Recoveries for phthalates at spiking levels in different matrices were satisfactory (between 68% and 115%). Moreover, the results were further confirmed by comparing them with those obtained using a solvent extraction method according to the national standard of China.     

碳纳米管/聚偏氟乙烯纳米纤维膜的制备及其压电性能

为提高聚偏氟乙烯(PVDF)的压电性能,采用静电纺丝法将碳纳米管(CNTs)引入到PVDF纳米纤维膜中制备CNTs/PVDF纳米纤维膜,并组装成三明治结构的柔性压电传感器,探究CNTs质量分数对CNTs/PVDF纳米纤维膜压电性能的影响.借助扫描电子显微镜、X射线衍射仪、傅里叶变换红外光谱仪、万能试验机以及数字示波器对...     

Quantification of caffeine in dietary supplements and energy drinks by solid-surface fluorescence using a pre-concentration step on multi-walled carbon nanotubes and Rhodamine B

A new method for the determination of caffeine, a non-fluorescent analyte, based on the enhancement of the fluorescence of Rhodamine B dye on a membrane filter modified with multi-walled carbon nanotubes is proposed. The method comprises pre-concentration of caffeine on a solid support by chemofiltration in buffered solution onto multi-walled carbon nanotubes previously oxidised and dispersed in cationic surfactant admicelles. The effect of experimental parameters, including the nature of the buffer and pH, the nature of the solid support, filtration flow rate, dye and carbon nanotube concentration, and the nature of the surfactant and concentration were investigated by means univariation assays. Under optimum experimental conditions, the pre-concentration system gave detection and quantification limits of 0.3 and 1.1 µg l^?1, respectively. A wide linear range was achieved varying from concentrations of 1.1 to 9.7 × 103 µg l^?1 (r² = 0.999). Satisfactory recovery values were obtained using the method of standard addition, confirming the feasibility of this method for caffeine determination in energising dietary supplements and energy drinks.     

聚酰胺66/氨基化多壁碳纳米管纤维制备及其性能

为提高聚酰胺66(PA66)纤维的力学性能,将羧基化碳纳米管(CMWNTs)与乙二胺(EA)进行功能化反应得到氨基化碳纳米管(AMWNTs),再将AMWNTs与PA66盐原位聚合制备AMWNTs掺杂PA66材料(PACNTs),并通过熔融纺丝制备成纤维。采用热重分析仪、差示扫描量热仪、X射线衍射仪及单纤维强力仪等对PA66和PACNTs纤维进行结构和性能表征。结果表明:PACNTs纤维的熔点随着AMWNTs的加入向低温方向移动,AMWNTs的加入使PA66分子质量下降,PACNTs纤维的结晶温度向高温方向移动,AMWNTs起到异相成核作用;随着AMWNTs的加入,PACNTs纤维的拉伸强度和弹性模量增加,当AMWNTs质量分数为0.5%时,PACNTs纤维的拉伸强度和弹性模量达到最大,比纯PA66纤维分别提高了约157%和455%。     

多壁碳纳米管分散型固相萃取-高效液相色谱测定降糖保健食品中非法添加药物罗格列酮

本文建立多壁碳纳米管分散型固相萃取-高效液相色谱法测定降糖类保健食品中非法添加物罗格列酮的检测方法,重点考察了样品提取溶剂和提取时间、净化剂类型、组成、使用量和净化时间对回收率的影响。结果表明,样品前处理最优条件为:采用无水甲醇超声提取20 min,经多壁碳纳米管（MWCNTs）和N-丙基乙二胺（PSA）净化1 min。所建立的高效液相色谱法测定降糖类保健食品中罗格列酮的线性范围为1.0⁵0.0μg/m L,相关系数为0.9997,检出限和定量限分别是0.02μg/m L和0.06μg/m L。样品加标平均回收率为77.3%⁹3.2%,相对标准偏差（RSD）小于10%。该样品前处理方法简便、快速且成本较低,适用于批量保健食品中罗格列酮的快速检测。      

碳纳米管改性及其在食品检测中的应用进展

碳纳米管(CNT)是纳米碳材料中的一种新型材料,文章主要介绍碳纳米管的非共价键和共价键改性方法,及其在农药兽药残留、重金属检测、食品添加剂检测和转基因食品检测等食品安全领域中的应用,并探讨其在食品检测领域的发展方向。     

钴酞菁与碳纳米管共修饰碳纤维织物传感器的制备及其电化学性能

为探索钴酞菁(CoPc)/碳纳米管(CNT)柔性葡萄糖传感器在葡萄糖检测中的应用,制备了一种CoPc和CNT共修饰的柔性碳纤维织物(CFT)修饰电极,并利用电化学工作站的银/氯化银参比电极和铂对电极与其共同组成三电极体系的葡萄糖传感器.借助扫描电子显微镜对修饰电极进行表征,采用循环伏安法、电化学阻抗图谱法、时间-电流曲...     

基于碳纳米管富集净化作用和电化学特性的真菌毒素检测方法研究进展

真菌毒素污染是造成粮食和食品安全问题的重要因素之一,高效的真菌毒素分析检测方法,能够为真菌毒素的高通量快速筛查提供可靠的技术支持。近年来,碳纳米管成为真菌毒素检测领域的研究热点。碳纳米管具有吸附能力强、表面可修饰、易分离和良好的生物相容性等特点,在很多领域有着广阔的应用前景。本文根据碳纳米管的特性及真菌毒素的污染特点,对真菌毒素的检测现状作了简要介绍,对基于碳纳米管的真菌毒素检测技术研究进行综述,并展望了真菌毒素检测技术发展的新趋势。     

多壁碳纳米管调控聚乳酸-乙醇酸共聚物超细纤维的结构与性能

通过超声处理,将改性后的多壁碳纳米管与聚乳酸-乙醇酸共聚物制成共混纺丝液.将该纺丝液进行静电纺丝即可制备多壁碳纳米管／聚乳酸-乙醇酸共聚物复合超细纤维,并用场发射扫描电镜( FE-SEM)、差热分析( DSC)、热重分析(TGA)、多功能拉伸仪和透射电镜(TEM)对超细纤维的表面形貌、热性能、力学性能和多壁碳纳米管的分...     

碳纳米管固相萃取在食品安全检测中的应用进展

跟一般的吸附材料相比,碳纳米管具有比表面积大、化学性质稳定、机械稳定性和热稳定性好以及吸附能力强的优点,且固相萃取操作简便、萃取时间短、有机溶剂使用量少,碳纳米管作为吸附剂结合固相萃取用于食品样品的前处理显现出较好的效果。本文介绍了碳纳米管的功能化修饰及其吸附特性,主要综述了碳纳米管固相萃取在食品重金属、农药、兽药和有机污染物检测中的应用概况,并对碳纳米管固相萃取的应用现状及前景作了展望。      

Encapsulation of quantum dots and carbon nanotubes with polypyrrole in a syringe needle for automated molecularly imprinted solid phase pre-concentration of ochratoxin A in red wine analysis

Nanometer-sized semiconductor quantum dots (QDs with CdSe core and ZnS shell) and carbon nanotubes (CNTs with multi-walls) were encapsulated inside a stainless steel syringe needle by electrodeposition of polypyrrole (PPy). By cross-linking the PPy with ethylene glycol dimethacrylate (EGDMA) in the presence of ochratoxin A (OTA) as a template, molecularly imprinted polypyrrole (MIPPy) was formed on the nano-hybrid structure at an increased specific surface area. The MIPPy/CNTs/QDs-modified needle was readily adapted in an autosampler for micro-solid phase preconcentration (μSPP) of OTA from a red wine sample. After pulsed elution (PE) with 2% triethylamine (TEA), the OTA was determined by high performance liquid chromatography (HPLC) with fluorescence detection (FD). In comparison with MIPPy/CNTs, this new nano-hybrid structure of MIPPy/CNTs/QDs significantly improved the % recovery of OTA. The method, MIPPy/CNTs/QDs-μSPP-HPLC-FD, demonstrated that the MIPPy was truly a molecularly imprinted polymer (MIP) with specific recognition for OTA. All red wine matrix components could be differentially washed out, prior to accurate determination of the strongly bound OTA.