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1.
以双亲性无规聚合物和氯丙醇为组装基元,在选择性溶剂中制得氯丙醇分子印迹胶束,并将其电沉积在金电极表面得到分子印迹电化学传感器。采用Zeta电位及纳米粒度分析仪、透射电子显微镜表征了组装环境对形貌的影响。乳酸量、盐浓度和氯丙醇浓度对印迹胶束的组装行为有较大影响,当氯丙醇浓度为10~(-10)~10~(-4) mmol/L时制得的电化学传感器具有良好的线性响应。  相似文献   

2.
基于分子印迹电聚合膜的双酚A电化学传感器   总被引:3,自引:0,他引:3  
以双酚A为模板分子,邻氨基苯硫酚为单体,采用自组装和电聚合方法,在电极表面制备了对双酚A有选择性的分子印迹聚合物膜.通过循环伏安法研究传感器对双酚A的响应特性.结果表明: 在6.0×10-7~5.5×10-5 mol/L浓度范围内峰电流值与浓度呈良好线性关系(r=0.991);检出限2.0×10-7 mol/L; 相对标准偏差<5%(n=9),达到稳定电流所用时间约2 min.此传感器具有良好的选择性、重现性及稳定性.通过交流阻抗技术和计时电流法表征了电极表面膜的电化学性质.将传感器初步用于实际样品的分析,获得了较满意的结果.  相似文献   

3.
该工作通过电化学方法在多壁碳纳米管修饰的玻碳电极表面得到聚邻氨基苯酚分子印迹聚合物膜,制备了可以选择性识别双酚A的分子印迹电化学传感器。通过扫描电镜、循环伏安法以及差分脉冲法对传感器的表面形貌和电化学性能进行了表征,并对传感器的检测条件进行了优化。采用K_3[Fe(CN)_6]作为电化学探针,在选定的实验条件下,K_3[Fe(CN)_6]在印迹电极上的峰电流变化值与双酚A的浓度在1×10~(-10)-4×10~(-8) mol·L~(-1)呈良好线性,本方法测定双酚A的检测限为4×1 0 ~(-11) mol·L~(-1),将该传感器用于实际水样中双酚A的测定,结果令人满意。  相似文献   

4.
基于Au-Pd合金修饰的玻碳电极为工作电极,采用循环伏安法将邻氨基酚与尼古丁电沉积在工作电极上,制备了尼古丁分子印迹膜传感器。采用差分脉冲伏安法研究尼古丁在尼古丁分子印迹膜传感器上的电化学行为,考察了模板溶解时间、富集时间和溶液pH值对尼古丁测定的影响。在优化实验条件下,尼古丁分子印迹膜传感器的线性范围为1.2×10~(-7)~2.5×10~(-3) mol/L,检出限为4.6×10~(-8) mol/L。用该传感器对吸烟者血液中尼古丁的含量进行检测,结果表明,该传感器具有灵敏度高、线性范围宽、重现性及稳定性好等优点。  相似文献   

5.
采用石墨烯作为电极增敏材料,制备三唑磷(TAP)分子印迹电化学传感器。采用自由基聚合法,在石墨烯修饰电极(GR/GCE)上合成分子印迹聚合物膜(MIP)。利用微分脉冲伏安法、电化学阻抗谱对不同修饰电极进行电化学表征,利用微分脉冲伏安法考察了MIP和非分子印迹聚合物膜(NIP)传感器的电化学性能。在最优实验条件下,TAP浓度在1.0×10~(-7)~2.0×10~(-5)mol·L~(-1)内和MIP膜传感器峰电流呈线性关系,检出限为4.3×10~(-8)mol·L~(-1)(S/N=3)。建立MIP膜传感器的动力学吸附模型,测得结合速率常数k为9.0580 s。  相似文献   

6.
刘蓉  龙立平  刘石泉  赵运林  颜徐  李杰 《化学通报》2015,78(10):918-922
以槲皮素作为模板分子,邻氨基苯酚作为功能单体,在金电极表面通过电聚合法,制备了具有选择性识别槲皮素的分子印迹传感器。采用循环伏安法、差分脉冲伏安法研究了印迹膜的性能、结构和分子印迹效应。对功能单体与模板分子的配比、洗脱时间和印迹时间等实验参数进行了优化,并与其结构相似的化合物芦丁的选择性响应进行了比较,发现该传感器对槲皮素分子具有良好的选择性。槲皮素浓度在6.0×10-6~1.0×10-4mol/L范围内与峰电流呈线性关系,线性方程为:I(μA)=27.79+9.48lgc(mol/L)(R=0.9939),检出限为2.0×10-6mol/L。用此传感器测定黑茶中槲皮素含量的结果较为满意。  相似文献   

7.
以氧乐果为模板分子,邻苯二胺为功能单体,在碳纳米管修饰的玻碳电极表面通过电聚合方法制成氧乐果分子印迹聚合物膜,用无水乙醇洗脱后制备出对氧乐果有特异响应的电化学传感器。通过循环伏安法和电化学阻抗法对分子印迹传感器的电化学性能进行表征。以K_3Fe(CN)_6为探针,采用差分脉冲伏安法研究了该分子印迹传感器的分析性能,建立了氧乐果的间接测定方法。结果表明,K_3Fe(CN)_6的相对峰电流与氧乐果浓度在1.0×10~(-7)~2.0×10~(-6)mol/L范围内呈良好的线性关系,检出限为3.6×10~(-8)mol/L。  相似文献   

8.
在金电极表面滴涂石墨烯(GR),通过电沉积技术沉积纳米金(Au)构成石墨烯-纳米金修饰电极(Au-GR/GE)。以芦丁为模板分子,邻氨基酚为功能单体,通过电聚合反应在Au-GR/GE表面合成一种对芦丁具有特异性识别能力的分子印迹传感器膜(MIP)。采用循环伏安法(CV)、差分脉冲伏安法(DPV)研究了印迹膜的性能、结构和分子印迹效应,并与槲皮素进行了选择性响应的比较,发现此传感器对芦丁具有良好的选择性。在最佳实验条件下,其对芦丁浓度的定量测定线性范围为6.30×10-7~1.70×10-4mol/L,线性方程为I(μA)=3.8136-8.6247 lg c(mol/L),R=0.9961,检出限为2.10×10-7mol/L。  相似文献   

9.
彭友元 《分析测试学报》2013,32(12):1427-1432
以咖啡因为模板分子,通过电聚合邻苯二胺,在羧基化多壁碳纳米管修饰的玻碳电极表面制备了对咖啡因有特异响应的分子印迹聚合物膜。通过循环伏安法和线性扫描伏安法对传感器的性能进行表征,并优化了检测条件,研究了印迹传感器对模板分子咖啡因及其结构类似物的选择性响应。在最优实验条件下,电化学探针K3[Fe(CN)6]的峰电流与咖啡因浓度在2.0×10-7~2.0×10-5mol·L-1范围内呈良好的线性关系,检出限为4.0×10-8mol·L-1。该传感器应用于铁观音茶叶中咖啡因含量的测定,其回收率为94%~106%。  相似文献   

10.
在模板分子存在下,在金电极上自组装邻氨基苯硫酚(oATP),通过电聚合制得毒莠定印迹的oATP/金纳米粒子聚合薄膜及其安培传感器.采用循环伏安法和交流阻抗技术对传感器制备过程进行表征,用紫外光谱法研究了单体与模板间的相互作用.以K3Fe(CN)6为探针,示差脉冲伏安曲线的峰电流与毒莠定浓度在2.0×10^-7-2.4×10 4mol/L范围内呈现良好的线性关系(r=0.9963),毒莠定的检出限为6.5×10 8mol/L(S/N=3).将该印迹膜传感器用于环境水样加标回收检测,结果令人满意.  相似文献   

11.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

12.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

13.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

14.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

15.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

16.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

17.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

18.
19.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

20.
Quercetin, the polyphenolic compound, which has the highest daily intake, is well known for its protective effects against aging diseases and has received a lot of attention for this reason. Both quercetin 3-O-β-d-glucuronide and quercetin 3′-O-β-d-glucuronide are human metabolites, which, together with their regioisomers, are required for biological as well as physical chemistry studies. We present here a novel synthetic route based on the sequential and selective protections of the hydroxyl functions of quercetin allowing selective glycosylation, followed by TEMPO-mediated oxidation to the glucuronide. This methodology enabled us to synthesize the five O-β-d-glucosides and four O-β-d-glucuronides of quercetin, including the major human metabolite, quercetin 3-O-β-d-glucuronide.  相似文献   

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