共查询到18条相似文献,搜索用时 78 毫秒
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硫堇与DNA分子相互作用的电化学方法研究 总被引:8,自引:0,他引:8
采用交流阻抗技术和循环伏安法 ,研究了在硫堇自组装膜修饰金电极上 ,以及在硫堇或DNA吸附修饰的玻碳电极上 ,硫堇与DNA分子的相互作用;硫堇自组装膜修饰金电极与DNA分子作用后 ,阻抗增大 ,表明它们之间发生了作用 ;吸附在玻碳电极上的硫堇 (DNA)与DNA(硫堇 )作用后 ,峰电位和峰电流均发生了变化 ,结合光谱测定结果 ,表明硫堇与DNA分子间存在着嵌插、静电等作用 ,二者作用的反应速度与分子在电极上固定的位置有关;在PBS缓冲液中硫堇 -DNA的表观结合常数为4.9×104L·mol -1 ;交流阻抗技术和循环伏安法是研究小分子与DNA分子间相互作用的经济、快速、简便的方法 相似文献
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采用绿色环保、生物兼容的寡糖(γ-环糊精)配体,与钾合成新型金属有机骨架化合物K+-CDMOFs,并对其进行透射电镜、傅立叶红外光谱和X射线衍射表征。用循环伏安法和差分脉冲伏安法研究了铜离子在K+-CD-MOFs修饰玻碳电极上的电化学行为,并对电解液、p H值和扫速进行优化。结果显示,在p H 5.0醋酸缓冲溶液,扫描范围-0.4~0.4 V,扫速0.1 V/s的条件下,铜离子浓度在0.1~91.7 mg/L范围内与其峰电流呈良好线性关系,检出限(S/N=3)为0.018 mg/L,表明这种新型材料有较好的电化学活性。同时考察了钙、锌、镁、铅、镉、汞离子对铜离子测定的影响,结果显示合成材料表现出良好的选择性,除汞离子外,其他阳离子对峰电流无明显影响。该方法灵敏度高、重现性好、稳定性高,具有一定的抗离子干扰能力,可快速、准确用于工业废水中铜离子的测定。这种新型有机骨架材料制备的电化学传感器在重金属检测中具有一定的应用潜力。 相似文献
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以废弃杨树叶粉为原料,用微分脉冲伏安法测定了废弃杨树叶粉吸附水溶液中的铜离子。建立了微分脉冲伏安法测定铜离子的方法,在2.5×10~(-4)~2.5×10~(-7) mol/L范围内测定铜离子,检测限为2.51×0~(-8) mol/L,并用于铜离子在废弃杨树叶粉上吸附的研究,考察了铜离子浓度范围、吸附时间、温度、杨树叶粉用量对杨树叶粉吸附铜离子的影响。在40 mL含有铜离子(2.5×10~(-4) mol/L)的KCl(0.025mol/L)溶液中,0.1g杨树叶粉足以吸附99%的铜离子,0.3g的杨树叶粉吸附达到完全,表观一级吸附速率为0.004 37s~(-1),5min可近于吸附平衡。吸附不遵从Temkin等温吸附模型,升高温度不利于吸附过程。最大吸附量为63.48mg/g,可以用于自然pH值下污染水中铜离子的吸附去除。 相似文献
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通过共价自组装的方法制备了巯基乙酸单分子层修饰金电极.在含有铜离子的磷酸缓冲液中搅拌吸附,铜离子与修饰电极表面的巯基乙酸形成的活性配合物吸附在电极表面.用该电极对不同浓度的铜离子进行检测,发现峰电流随铜离子浓度的增大而增大,在0.05~1μmol/L之间出现良好的线性关系,其最低检测限可达10 nmol/L. 相似文献
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Dacarbazine (DTIC) is a chemotherapy drug that is used for the treatment of Hodgkin's lymphoma, malignant melanoma, childhood solid tumors and soft tissue sarcoma. The surface confined interaction between DTIC and nucleic acids was investigated for the first time in this study by using both differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) in combination with disposable pencil graphite electrodes. The oxidation signals of DTIC and guanine were measured before and after interaction process using DPV technique. The interaction of DTIC with nucleic acids; poly[A], poly[G], or double stranded of poly[A]‐poly[T] and poly[G]‐poly[C] was also examined using DPV. Furthermore, EIS technique was utilized for detection of the interaction between DTIC and nucleic acids; ssDNA/dsDNA, poly[A], poly[G], or double stranded poly[A]‐poly[T] and poly[G]‐poly[C]. 相似文献
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硒代蛋氨酸与铜离子的相互作用(英文) 总被引:2,自引:0,他引:2
采用循环伏安法和库仑法研究了硒代蛋氨酸(SeMet)与铜离子的相互作用.当SeMet不存在时,铜离子在-132和71mV有一对氧化还原峰(峰Ⅴ,Ⅵ).当铜离子与SeMet共存时,配合物在14,128,271,-194mV有4个峰(峰Ⅰ,Ⅱ,Ⅲ,Ⅳ).扫描电位从600mV到-600mV时,Cu(Ⅱ)-(SeMet)2配合物在14mV时被还原为Cu(I)-SeMet配合物;Cu(Ⅰ)-SeMet配合物在-194mV被还原为Cu(0)和SeMet.由-600mV回扫时,还原产物被逐次氧化为Cu(Ⅰ)-SeMet配合物(128mV)和Cu(Ⅱ)-(SeMet)2配合物(271mV).同时发现Cu(Ⅰ)-SeMet配合物在电位-100mV至200mV间是稳定的,Cu(Ⅰ)的氧化还原过程被观察到.此外,采用毛细管电泳法测得二元Cu-SeMet配合物的稳定常数(K1和K2)分别为2.24×107和2.24×106.最后,推测Cu-SeMet配合物的结构为:在pH3.9时,铜离子通过Cu—Se和Cu—OCO键与SeMet发生配位作用;在生理条件时,铜离子通过Cu—N和Cu—OCO键与SeMet发生配位作用. 相似文献
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Studies on Electrochemical Behavior of Bleomycin and Its Interaction with DNA at a Co/GC Ion Implantation Modified Electrode 总被引:2,自引:0,他引:2
IntroductionIonimplantationisakindofnewmaterialsurfacemodificationtechnique .Recently ,Lietal .1haveledthistechniqueintoanalyticalchemistryandmademodi fiedelectrodewithparticularfunction .Ithasbeenap pliedtostudytheelectrochemicalbehaviorsandthede terminat… 相似文献
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利用银离子(Ag+)可与DNA中胞嘧啶碱基(C)相互作用的性质, 构建了一种用于检测Ag+的比率型电化学传感器. 以铬金属有机骨架材料(Cr-MIL-101 NH2)标记的单链DNA作为信号探针(Cr-MOFs-SP), 电解质溶液的二茂铁甲酸作为内部参考探针(Fc-RP), 在Ag+存在的情况下, 可以检测到Cr-MOFs的信号. 同时, 二茂铁甲酸的信号几乎保持稳定, 因此, Ag+浓度可以通过ICr-MOFs-SP/IFc- RP的比率响应进行监测. 所制备的比率型生物传感器可有效消除外界环境影响和避免电化学背景信号, 提高了检测的重现性、 准确性和灵敏度. 具有三维结构的DNA四面体纳米材料(NTH)可有效消除DNA的非特异性吸附. 同时, 所设计的DNA NTH增强了机械刚度, 可以增加Ag+的捕获量和信号物质的负载量, 进一步提高了检测灵敏度. 该比率型生物传感器对Ag+的检测具有良好的选择性、 较宽的线性范围(0.1~100 nmol/L)和较低的检出限(33 pmol/L). 将此传感器用于滇池水样中Ag+的含量测定, 回收率为96.8%~103.0%, 表明此传感器具有潜在的实际应用前景. 相似文献
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In this study, interaction of tetracycline (TC) and DNA in the Britton? Robinson buffer solution (BR) was studied by cyclic voltammetry. The experimental results reveal that TC can bind strongly to DNA and the association constant and binding number between TC and DNA was obtained. Then DNA was immobilized on a glassy carbon electrode by UV‐irradiation. Through this process, water‐soluble DNA was converted into insoluble materials, and a stable DNA film was formed on the electrode. The electrochemical oxidation behavior of TC was studied at UV‐irradiated DNA film modified glassy carbon electrode (UV‐DNA‐GCE). The response of modified electrode was optimized with respect to pH, accumulation time, ionic strength, drug concentration and other variables. TC at the surface of modified electrode showed a linear dynamic range of 0.30–90.00 µM and a detection limit of 0.27 µM. To demonstrate the applicability of the modified electrode, it was used for the analysis of real samples such as pharmaceutical formulations and milk. 相似文献
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We present a new strategy for the label‐free electrochemical detection of DNA hybridization based on gold nanoparticles (AuNPs)/poly(neutral red) (PNR) modified electrode. Probe oligonucledotides with thiol groups at the 5‐end were covalently linked onto the surface of AuNPs/PNR modified electrode via S‐Au binding. The hybridization event was monitored by using differential pulse voltammetry (DPV) upon hybridization generates electrochemical changes at the PNR‐solution interface. A significant decrease in the peak current was observed upon hybridization of probe with complementary target ssDNA, whereas no obvious change was observed with noncomplementary target ssDNA. And the DNA sensor also showed a high selectivity for detecting one‐mismatched and three‐mismatched target ssDNA and a high sensitivity for detecting complementary target ssDNA, the detection limit is 4.2×10?12 M for complementary target ssDNA. In addition, the DNA biosensor showed an excellent reproducibility and stability under the DNA‐hybridization conditions. 相似文献
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柔红霉素在钴离子注入修饰玻碳电极上与DNA相互作用 总被引:1,自引:0,他引:1
用钴离子注入修饰电极研究了柔红霉素与DNA的相互作用.柔红霉素以嵌入方式与DNA发生作用,形成非电活性的结合物.加入DNA后,柔红霉素的电化学行为没有改变,仍为扩散控制.用非线性拟合得到柔红霉素与DNA的结合常数K=1.09×108cm3/mol,结合数s≈4.DNA分子结构中的1个螺旋结合2个柔红霉素. 相似文献