Rapid detection of chlorpheniramine maleate by an electrochemical sensor based on metal-organic frameworks CHP@Cu3（BTC）2 /MWCNTsEI北大核心CSCD

Copper hydroxyphosphate@metal-organic frameworks/multi-wall carbon nanotube composites （CHP@Cu3 （BTC）2 /MWCNTs）were prepared by a new in-situ template method and then an electrochemical sensor was developed based on the composites. The crystal structure and morphology of the material were characterized by X-ray diffraction and scanning electron microscope. Cyclic voltammetry and linear sweep voltammetry were used to study the electrochemical catalytic performance,and the determination conditions were optimized. The rapid and sensitive detection of chlorphenamine maleate was realized. There was a good linear relationship between the oxidation peak current and concentration of chlorphenamine maleate in the ranges from 5 to 100 µμmol/L and from 150 to 800 µμmol/L,and the linear equations were as Ipa （µμA）=0.1559c（µμmol/L）-0.3533 （R2 =0.9973）and Ipa （µμA）=0.02328c（µμmol/L）+16.63（R2 =0.9594）,and the detection limit was 1.67 µμmol/L. The recoveries of the actual drug ranged from 91.0% to 109.1%. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

A Novel Cholesterol Oxidase Biosensor Based on Pt-nanoparticle /Carbon Nanotube Modified Electrode

A variety of electrochemical biosensors for cholesterol detection have been proposed because of its importance in clinic and food analysis 1-2. Classical devices for the detection were based on monitoring either the consumption of oxygen or the production of H2O2. The amperometric determination of H2O2 oxidation is sensitive and stable, but it requires a high anodic potential (over 0.6 V vs Ag/AgCl) and is affected by co-oxidable substances such as ascorbic acid and uric acid usually presen…     

基于纳米MnO2-MWCNTs复合材料修饰的葡萄糖传感器

采用水热法制备了纳米MnO2,并用红外光谱,X射线衍射(XRD)和扫描电子显微镜(SEM)对其进行了表征。将碳纳米管和纳米MnO2分散在壳聚糖溶液中,用滴涂法固定到玻碳电极表面,制成修饰电极。利用计时电流法对该葡萄糖传感器的性能进行了研究,纳米MnO2-MWCNTs复合物对葡萄糖的氧化有明显的催化作用。在优化的条件下,葡萄糖在5.0×10-5～3.0×10-2mol/L浓度范围内,计时电流与浓度之间呈线性关系,检出限为1.5×10-5 mol/L(S/N=3)。对1.0×10-3 mol/L葡萄糖溶液平行测定8次的相对标准偏差(RSD)为2.1%。该传感器可成功用于葡萄糖注射液中葡萄糖的测定,回收率在96.4%～98.6%之间。     

基于聚多巴胺球负载Cu纳米粒子的催化作用分光光度法测定人血中葡萄糖含量北大核心CSCD

用水热法在聚多巴胺球(PDA)表面负载了Cu纳米粒子(Cu@PDA),制备了具有过氧化物酶活性的Cu@PDA复合物。此复合物能催化过氧化氢快速氧化无色还原态的四甲基联苯胺(TMB),使其转变为蓝色的氧化态TMB,其吸收峰波长为652 nm,其吸光度与过氧化氢的浓度有关。利用此催化反应结合葡萄糖氧化酶(Gox)催化经氧气氧化葡萄糖而产生过氧化氢的反应,提出了分光光度法测定血样中葡萄糖的方法。在总体积为10 mL的0.1 mol·L^(-1)磷酸盐缓冲溶液(pH 4.0)中含1.0 mg·L^(-1)Cu@PDA,4.0 g·L^(-1)Gox,0.5 mmol·L^(-1)TMB的条件下加入血样,于40℃反应10 min时,葡萄糖浓度在1.0~30.0 mmol·L^(-1)的范围内与相应的吸光度之间呈线性关系,检出限(3S/N)为0.3 mmol·L^(-1)。方法应用于人血样品的分析,所测得葡萄糖含量与医院实验室所给的值相符。     

碳纳米管改性苯乙烯-丙烯腈共聚物/聚脲纳米复合泡沫北大核心CSCD

聚合物纳米复合泡沫通常具有优于常规泡沫的综合性能。通过“增塑-发泡-增强”策略与多壁碳纳米管(MWCNTs)复合改性相结合的方法,制备出了MWCNTs改性的苯乙烯-丙烯腈共聚物/聚脲(SAN/PUA)纳米复合泡沫,并对加入MWCNTs后SAN/聚脲交联单体(SAN/CMs)共混体系的粘弹性和发泡性能以及对所制备的SAN/PUA纳米复合泡沫的耐热性能、导电性能和电磁屏蔽性能等进行了研究。结果表明,MWCNTs的加入可以有效减小SAN/PUA复合泡沫的最终泡孔尺寸,但不影响CMs对SAN的增塑效果;MWCNTs改性的SAN/PUA纳米复合泡沫比纯SAN(116.4℃)泡沫具有更好的耐热性能(128.1~139.3℃)。随着MWCNTs质量分数的增加,泡沫的储能模量增大,且导电性能和电磁屏蔽性能也增强;当MWCNTs质量分数为15%时,SAN/PUA纳米复合泡沫的电磁屏蔽性能达到30.7 dB。另外,研究发现,随着MWCNTs质量分数的增加,泡沫的电磁屏蔽能力将由吸收主导转变为反射主导。     

Electrochemical detection of bisphenol A based on Co nanoparticles/N-doped carbon nanotubes compositesEI北大核心CSCD

Co nanoparticles and nitrogen-doped carbon nanotubes （NCNTs）were prepared by calcination of metal-organic material ZIF-67 in a reductive atmosphere of H2 and Ar gas,and modified on the surface of glassy carbon electrod（GCE）for the detection of bisphenol A（BPA）. The Co/NCNTs composites exhibited superior electrocatalytic performance for BPA oxidation owing to the synergistic effect between chemical composition and the specific structure of the Co/NCNTs composites. In optimal conditions,Co/NCNTs/GCE exhibited a linear range of 0.01-20 μµmol/L for BPA（R2=0.998）. The prepared electrode was employed to detect the content of BPA in real samples with the recoveries of 98.4%-104.6%. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

基于血红蛋白/金纳米粒子/聚二烯丙基二甲基氯化铵-多壁碳纳米管生物传感器测定过氧化氢

将分散于聚二烯丙基二甲基氯化铵(PDDA)中的多壁碳纳米管(MWCNT′s)滴涂在玻碳电极(GCE)表面制成PDDA-MWCNT′s/GCE修饰电极(简称电极Ⅰ);在氯金酸溶液中用恒电位沉积法使金纳米颗粒(AuNP′s)积镀于电极Ⅰ表面,制得AuNP′s/PDDA-MWNCT′s/GCE修饰电极(简称电极Ⅱ);将血红蛋白(Hb)滴于电极Ⅱ表面,用磷酸盐缓冲溶液冲洗后制成可供测定过氧化氢用的生物传感器Hb/AuNP′s/PDDA-MWCNT′s/GCE(简称电极Ⅲ)。与裸GCE、电极Ⅰ和Ⅱ相比较,在pH 6.8的磷酸盐缓冲溶液中,过氧化氢在电极Ⅲ上的还原峰电流明显提高,其值与过氧化氢浓度在1.0～1 800μmol.L-1范围内呈线性关系,其检出限(3S/N)为0.8μmol.L-1。应用此生物传感器测定消毒液中过氧化氢的含量,测定值与高锰酸钾滴定法的测定值相符。     

Construction and application of an electrochemical sensor based on graphene-MXene nanocomposites for baicalin detectionEI北大核心CSCD

Redox graphene-MXene(rGO-MXene) nanocomposites were prepared by ion polymerization and used to construct a highly sensitive electrochemical sensor for baicalin(BA) detection. The synergistic effect of rGO and MXene increased the specific surface area and electron transport capacity of the electrode, and significantly enhanced the electrochemical response of BA. The cyclic voltammetry and differential pulse voltammetry were used to investigate the electrochemical behavior of BA on the sensor. Under the optimal conditions, the peak current exhibited a good linear relationship with BA concentration in the range of 0. 05-10 μmol / L, and the limit of detection was as low as 28 nmol / L. The method was applied to analyze traditional Chinese medicine preparations containing baicalin, such as Qingkailing Capsule and Sanhuang Tablets with good accuracy and spiked recovery. The results were highly consistent with those of high performance liquid chromatography, providing a technical means for the rapid and sensitive detection of traditional Chinese medicine preparations. © 2022, Youke Publishing Co.,Ltd. All rights reserved.     

钴镍笼状双金属氢氧化物/多壁碳纳米管复合材料对环境水样中农药的高效富集北大核心CSCD

建立高效、灵敏的农药分离、富集和检测方法具有重要意义。该实验采用一步法合成了钴基沸石咪唑骨架/多壁碳纳米管(ZIF-67/MWCNTs)复合物,并以该复合物为模板通过溶剂热法合成了钴镍笼状双金属氢氧化物/多壁碳纳米管(CoNi-LDH/MWCNTs)复合材料,将CoNi-LDH/MWCNTs用作固相微萃取(SPME)的纤维涂层富集环境水样中的6种农药,结合高效液相色谱(HPLC)测定了环境水样中的6种农药。通过扫描电镜、能谱分析、红外光谱、粉末X射线衍射和N吸附/脱附对所制备的各种材料进行了表征。利用正交设计试验优化SPME的萃取条件,包括萃取温度、萃取时间、搅拌速率、解吸时间和盐浓度。在最优化的条件下,该方法具有较宽的线性范围(百菌清为0.015~200μg/L,戊唑醇为0.140~200μg/L,毒死蜱为0.250~200μg/L,仲丁灵为0.077~200μg/L,溴氰菊酯为1.445~200μg/L,哒螨灵为0.964~200μg/L)、较低的检出限(0.004~0.434μg/L)和良好的重复性。单个纤维和不同批次纤维间的相对标准偏差(RSD)分别为0.5%~5.7%和0.5%~4.8%。在10.0μg/L和50.0μg/L 2个水平下的加标回收率为83.9%~108.2%,RSD<5.3%。此外,与其他涂层纤维相比,CoNi-LDH/MWCNTs涂层对农药具有更高效的富集能力,这归因于它的高比表面积以及CoNi-LDH/MWCNTs涂层与目标分析物之间存在的π-π堆积作用、疏水作用、阳离子-π相互作用和氢键作用。该方法可以实现环境水样中农药残留的高选择性、高灵敏度及高准确性的分析测定。     

Ni修饰碳纳米管促进合成气高效制甲醇Cu基催化剂研究

利用化学还原沉积法,制备一类Ni高度分散/修饰的多壁碳纳米管基新型材料y%Ni/MWCNT(y%为质量百分数),并用其作为促进剂,制备共沉淀型y%Ni/MWCNT促进的合成气高效合成甲醇Cu-ZnO-Al₂O₃催化剂,Cu₆Zn₃Al₁-x%(y%Ni/MWCNT)(x%为质量百分数).实验发现,Ni对MWCNT的预修饰能明显地提高单纯MWCNT促进的Cu-ZnO-A1₂O₃催化剂对合成气转化为甲醇的催化活性.在2.0 MPa,493 K,V(H₂):V(CO):V(CO₂):V(N₂)=62:30:5:3,GHSV=2700 mL(STP)·h^-1·(g-cat.)^-1的反应条件下,所观测CO转化率达34%,相应甲醇时空产率为442 mg·h^-1·(g-cat.)^-1,分别是非促进的基质催化剂Cu₆Zn₃Al₁[最佳操作温度513 K时为320 mg·h^-1·(g-cat.)^-1]和单纯MWCNT促进的催化剂Cu₆Zn₃Al₁-12.5%MWCNT[最佳操作温度503 K时为378 mg·h^-1·(g-cat.)^-1]的1.38和1.17倍.在反应温度≤503 K时产物中甲醇的选择性≥98%;当反应温度＞503 K时有可观量CH₄的生成,其选择性随催化剂中M含量及反应温度上升而增加.为兼获较高的CO转化率及相应甲醇选择性,催化剂的组成以Cu₆Zn₃Al₁-12.5%(8%Ni/MWCNT)为佳,反应温度以～493 K为宜.结合催化体系的表征(XRD,TPR,TPD)等结果,讨论了y%Ni/MWCNT促进剂的作用本质.     

碳纳米管负载铂-二氧化钌纳米颗粒用于葡萄糖传感器的研究

建立了多壁碳纳米管(MWNTs)负载铂二二氧化钌纳米颗粒的液相化学还原法.以Nafion为固定剂,将Pt-RuO2/MWNTs复合材料修饰于玻碳电极的表面,制备了一种无酶型葡萄糖传感器.实验表明:复合材料修饰的电极对葡萄糖响应电流明显,并且受抗坏血酸(AA)、多巴胺(DA)和尿酸(UA)的干扰小.本实验采用安培法测定葡萄糖,线性范围为2 0×10 3～1.0×10-2 mol/L(R～0.9965);灵敏度为119.26 μA cm-2(mmol/L)-1;检出限为1.25×10 -5 mol/L(信噪比为3);响应时间为4.8 s.PtRuO2/MWNTs修饰电极可作为性能良好的无酶型葡萄糖传感器.     

基于Au@N-CDs纳米复合材料电化学传感器检测左氧氟沙星北大核心CSCD

本文以富氮生物物质为前驱体合成氮掺杂碳点(N-CDs),调控反应时混合溶液pH值,协同发挥N-CDs还原性和稳定性效应,还原HAuCl_(4)生成并稳定Au纳米粒子(AuNPs),以水浴孵化法制备Au@N-CDs纳米复合材料。基于AuNPs良好电催化能力,N-CDs高比表面积和对左氧氟沙星(LEV)亲合力,提高玻碳电极(GCE)对LEV检测的选择性和灵敏度。在pH=6.0磷酸盐缓冲溶液中,于电位0.4V下富集125s,Au@N-CDs/GCE可在利福平、罗红霉素、红霉素等抗生素共存情况下选择性检测LEV,检出限和线性范围分别为1.0×10^(-6) mol/L和2.5×10^(-6)~1.0×10^(-4) mol/L。该法成功应用于人体尿样中LEV测定,回收率为93.0%~107.4%,相对标准偏差为2.98%。     

金纳米粒子/碳纳米管修饰电极吸附伏安法测定微量间苯二胺

运用循环伏安法及线性扫描伏安法研究了间苯二胺在金纳米粒子/碳纳米管修饰玻碳电极上的电化学行为,优化并建立了一种直接测定间苯二胺的电化学分析方法。结果表明,与裸玻碳电极相比,金纳米粒子/碳纳米管修饰电极能显著提高间苯二胺的氧化峰电流。在优化条件下,氧化峰电流与间苯二胺浓度在3.0×10-8~1.0×10-6mol/L范围内呈现良好的线性关系,检出限为1.0×10-8mol/L,对1.0×10-7mol/L的间苯二胺溶液平行测定10次的RSD为4.2%。测定了实验室废水中的间苯二胺含量,3次测定结果的平均回收率为99.7%,RSD为2.1%。     

电化学传感器在H_2O_2检测中的应用

将辣根过氧化酶(HRP)固定在壳聚糖(CTS)-羧基化多壁碳纳米管(C-MWNTs)复合物修饰的玻碳电极(GCE)表面,制得壳聚糖-羧基化多壁碳纳米管(HRP-CTS/C-MWNTs/GCE)电化学传感器。采用傅立叶变换红外光谱仪检测复合物包埋的HRP,发现其结构性质未发生改变;采用循环伏安法对该电极的电化学性能进行研究,结果表明:在1/15 mol·L~(-1)的PBS(pH 6.98)缓冲溶液中出现1对氧化还原峰,传感器对过氧化氢有良好的电催化还原作用。过氧化氢浓度在0.1~12 mmol·L~(-1)范围内与还原峰电流呈线性关系,相关系数(r)为0.998 6,并检测出市售医用双氧水的平均含量为2.93%。     

金纳米粒子/聚多巴胺/碳纳米管修饰玻碳电极对核黄素的测定

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.     

基于多壁碳纳米管和聚十六烷基三甲基溴化铵修饰玻碳电极的电化学法快速测定水和土壤中双酚A的含量北大核心CSCD

基于多壁碳纳米管(MWCNTs)和聚十六烷基三甲基溴化铵(p-CTAB)的高导电性、高增敏性,制备了MWCNTs、p-CTAB修饰的玻碳电极(GCE),将其作为工作电极(MWCNTs/p-CTAB/GCE),用于快速测定水和土壤中双酚A(BPA)的含量。以GCE为工作电极,采用循环伏安法(CV)对0.5 g·L^(-1) CTAB溶液扫描20圈,得到p-CTAB修饰的GCE(p-CTAB/GCE);吸取1.96 g·L^(-1) MWCNTs标准溶液5μL,滴涂在p-CTAB/GCE表面,干燥后得到MWCNTs/p-CTAB/GCE。水样经过滤,分取2 mL与0.3 mol·L^(-1)磷酸盐缓冲溶液(pH 7.0)8 mL混匀后待测;土壤样品25 g经风干、研磨、过筛后,用乙醇50 mL提取两次,浓缩至约1 mL,用无水乙醇定容至10 mL,分取2 mL与0.3 mol·L^(-1)磷酸盐缓冲溶液(pH 7.0)8 mL混匀后待测。以MWCNTs/p-CTAB/GCE为工作电极,钛棒为对电极,饱和甘汞电极为参比电极,设置搅拌速率为800 r·min^(-1),于0.2 V富集待测样品溶液中的BPA 150 s,采用差分脉冲伏安法(DPV)测定BPA的含量。扫描电子显微镜表征结果显示,MWCNTs/p-CTAB/GCE表面呈多孔空隙和多孔网状结构。以DPV、CV和电化学阻抗谱法考察了BPA在MWCNTs/p-CTAB/GCE上的电化学行为,结果表明BPA在该电极上的电化学氧化反应是一个受吸附控制的不可逆反应,BPA的浓度在0.08~20μmol·L^(-1)内与其对应的氧化峰电流呈线性关系,检出限为0.02μmol·L^(-1)。用同一支MWCNTs/p-CTAB/GCE重复测定BPA标准溶液10次,测定值的相对标准偏差为5.0%。对实际样品进行加标回收试验,BPA的回收率为82.0%~106%,测定值的相对标准偏差(n=5)为1.6%~8.1%。     

The detection of bergenin based on the gold nanoparticles/chitosan/reduced graphene oxide modified electrodeEI北大核心CSCD

Gold nanoparticles (AuNPs)/chitosan (CS)/reduced graphene oxide (RGO) modified electrode was prepared. The electrochemical behaviors of bergenin on this modified electrode was investigated by cyclic voltammetry. The results showed that the proposed electrode exhibited an obvious electrocatalytic ability to the oxidation of bergenin. The differential pulse voltammetry was employed to detect bergenin in 0.1 mol/L phosphate buffer solution (pH 6.0). A good linear relationship between the oxidation peak current and the concentration of bergenin was found in the range of 2.0×10-7-1.2×10-6 mol/L with the detection limit of 6.0×10-8 mol/L (S/N=3).The prepared electrode had good anti-interference ability and potential application in the actual detection of bergenin. © 2023, Youke Publishing Co.,Ltd. All rights reserved.     

钯铜合金纳米复合物电化学检测对乙酰氨基苯酚

通过水热合成法将钯铜(PdCu)纳米粒子负载于多壁碳纳米管(MWCNTs),从而制备了多壁碳纳米管钯铜纳米复合材料(PdCu@MWCNTs)。该复合物电子传递阻力低,比表面积大,具有良好的电催化活性。将该纳米复合材料修饰在玻碳电极上实现了对乙酰氨基苯酚(PCT)的灵敏检测。在最优的实验条件下,峰电流与对乙酰氨基苯酚浓度在0.15μmol/L～60μmol/L之间线性良好,相关系数R²=0.990,检出限(S/N=3)为0.13μmol/L。该传感器具有良好的选择性,稳定性和重复性,可用于市售剂中对乙酰氨基苯酚的检测。     

基于壳聚糖/TiO2新型杂化材料的过氧化氢传感器

制备了一种新型有机-无机杂化材料,这种杂化材料由二氧化钛溶胶和壳聚糖组成,此杂化材料克服了普通溶胶-凝胶易脆裂的特点,可以有效地保留被包埋的 Hb 生物催化活性;而且碳纳米管和纳米铜的协同效应提高了对过氧化氢的催化性能和促进了电子的传递.研究了各种因素对传感器响应电流的影响.对过氧化氢响应线性范围 1.0×10-7～1...     

Construction and application of carbon nanotube/polypyrrole-based bacterial surface imprinted sensorEI北大核心CSCD

A simple and fast "non-hole" bacteria surface imprinted (SPBIP) impedance sensor was constructed for ultrasensitive detection of Salmonella. The SPBIP sensor was prepared by one step electropolymerization of pyrrole (functional monomer), single-walled carbon nanotube (SWNT, nano-modulator), and Salmonella(template) onto a glassy carbon electrode. After removing the bacterial template, "non-hole" imprinted sites were formed on the surface of the polymer matrix, allowing the target bacteria to be specifically recognized. The resulting changes in the electrode surface impedance could be used to detect the target bacteria. The effects of the amount of SWNT, polymerization cycles, eluents, elution time and recognition time on the recognition ability of the sensor were investigated. Under the optimal conditions, the sensor could be used to detect 10~1×107 CFU/mLSalmonella with the limit of detection of 3.5 CFU/mL. The sensor could be used for the detection of salmonella in drinking water and orange juice samples with the recoveries ranging from 95.4% to 109.5%. © 2023, Youke Publishing Co.,Ltd. All rights reserved.