基于纳米银与有机多孔材料/纳米金修饰的甲胎蛋白免疫传感器研究

在金电极表面电沉积银为氧化还原探针,利用有机多孔材料(PTC-NH2)、纳米金(nano-Au)固载甲胎蛋白抗体(anti-AFP),制备出用于检测甲胎蛋白(AFP)的安培型免疫传感器。通过交流阻抗技术、循环伏安法研究了电极的电化学特性,考察了孵育时间、测试液pH值等实验条件对传感器性能的影响,并利用扫描电子显微镜(SEM)对电极的修饰过程进行了表征。该传感器对AFP有良好的电流响应,线性范围分别为1.0～20.0ng/mL和20.0～60.0 ng/mL,检测限为0.6 ng/mL。     

基于磁性Fe_3O_4/Au-Pt纳米复合物构建甲胎蛋白免疫传感器的研究

制备了磁性Fe3O4/Au-Pt纳米复合物,将该纳米复合物修饰在玻碳电极表面,用牛血清蛋白封闭电极表面非特异性吸附位点。通过循环伏安法对电极的制备过程以及响应性能进行表征。实验结果表明,该修饰电极对甲胎蛋白(AFP)有良好的电流响应,在甲胎蛋白浓度为0.05~1.0ng/mL和1.0~100.0ng/mL两个范围内,分别呈良好的线性,检出限为0.01ng/mL。该免疫传感器制备方法简单,灵敏度较高,有望应用于临床医学中检测人体血清中甲胎蛋白含量。     

高灵敏甲胎蛋白夹心免疫传感器的制备

构建了新型甲胎蛋白(AFP)夹心免疫传感器.采用金纳米粒子-氧化石墨烯-普鲁士蓝纳米立方体(AuNP-GO-PBNCs)纳米复合材料标记甲胎蛋白(AFP)二抗,将制备的金-聚多巴胺-四氧化三铁(Au-PDA-Fe3O4)磁性纳米复合物固定在自制的磁性电极表面,通过吸附作用固定AFP一抗,用牛血清白蛋白(BSA)封闭电极上的非特异性吸附位点.在37℃下与AFP抗原溶液孵育50 min,最后将电极放入AuNP-GO-PBNCs纳米复合材料标记的二抗溶液中孵育,基于此建立了采用普鲁士蓝(PB)标记的的夹心免疫传感器检测AFP的方法.在最佳实验条件下,PB催化H2O2氧化的响应电流与AFP的浓度表现出两段线性关系,线性范围分别为0.005~1.000 ng/mL和1~20 ng/mL, 检出限(LOD, S/N=3)为1.0 pg/mL.本方法具有灵敏度高、选择性好的特点.     

基于纳米四氧化三铁-二茂铁构建甲胎蛋白免疫传感器的研究

用对交联剂1-乙基-3-(3-二甲基氨苪基)-碳化二亚胺/N-羟基琥珀酰亚胺将壳聚糖中的氨基与二茂铁甲酸中的羧基交联,并将制备好的纳米四氧化三铁加入其中反应形成富含氨基和羧基的磁性纳米复合物。该纳米复合物修饰到金电极表面,通过氨基及静电作用,吸附纳米金溶胶及甲胎蛋白抗体(anti-AFP)含量,从而成功制得高灵敏电流型甲胎蛋白免疫传感器。通过循环伏安法考察了电极表面的电化学特性。研究了孵育时间、温度、pH对免疫传感器的影响。在最优实验条件下,甲胎蛋白(AFP)质量浓度在0.01~10 ng/mL和10~120 ng/mL范围内,该免疫传感器的还原峰电流值与AFP的质量浓度有良好的线性关系,检出限为3 pg/mL。     

爆米花型金纳米用于信号放大构建夹心型免疫传感器测定甲胎蛋白

通过原位合成法以金纳米种子作为母核诱导纳米金在其表面原位生长生成爆米花型金纳米粒子,标记甲胎蛋白抗体(anti-AFP)和辣根过氧化物酶(HRP)结合形成免疫复合物(antiAFP@popcorn-shaped GNP@HRP)作为检测抗体。氧化石墨烯-亚甲基蓝-金纳米粒子(GOM B-AuNPs)纳米复合材料滴涂到玻碳电极(GCE)表面,形成纳米复合物用于捕获甲胎蛋白抗体构建了免疫传感平台(anti-AFP/GO-MB-AuNPs/GCE)。实验采用夹心型免疫分析模式,功能化爆米花型金纳米材料与石墨烯纳米复合物呈现出良好的性能,建立了一种可行的电流型免疫分析法用于灵敏分析血清样品中甲胎蛋白AFP。在优化的实验条件下,免疫传感器DPV电流响应与AFP浓度的对数值呈正比,线性范围为0.001~20 ng/mL,检测限为0.31 pg/mL(S/N=3)。制备的免疫传感器有良好的精密度,选择性和稳定性,可初步应用于临床检验中AFP测定。     

基于丝网印刷电极的甲胎蛋白电化学免疫传感器

报道了一种基于金纳米粒子(AuNPs)双重信号放大的高灵敏电化学免疫传感器,并应用于肝癌标志物甲胎蛋白(AFP)的检测。通过在丝网印刷电极(SPE)表面电沉积AuNPs提高电极的重现性,利用AuNPs的吸附作用固定AFP抗体,用于捕获样品中的待测AFP抗原,并进一步与固定了辣根过氧化物酶(HRP)标记检测抗体的纳米金免疫探针发生特异性结合,所形成的夹心免疫复合物可以催化底物得到响应电流。用扫描电镜(SEM)和微分脉冲伏安法(DPV)等技术研究电极组装过程以及电极的化学性质,讨论了影响免疫传感器性能的因素。在最优实验条件下,传感器的峰电流信号与AFP浓度在2.5~30ng/mL范围内呈良好的线性关系,检出限为0.16ng/mL。该传感器具有灵敏度高、成本低、仪器体积小的优点,具有较好的应用前景。     

基于纳米金/壳聚糖/石墨烯的癌胚抗原阻抗型免疫传感器

研究了在PBS缓冲介质中,一种检测癌胚抗原的新型免标记阻抗型免疫传感器的制备及应用,基于石墨烯、纳米金在玻碳电极表面组装制备传感器,通过循环伏安法、交流阻抗法对制备的传感器进行表征。在优化的实验条件下,该免疫传感器的阻抗值随着检测溶液中癌胚抗原(CEA)浓度的增大而增大,并在0.1～85 ng/mL CEA范围内呈线性关系,回归方程为△Ret=1605.55+39.26ρ;检测限为0.04 ng/mL(R=0.9992)。该免疫传感器可用于临床上对CEA的检测。     

基于脂质体信号增强癌胚抗原电化学免疫传感器的研究

研究了在玻碳电极利用巯基乙胺固定纳米金、然后纳米金固载癌胚抗体(Ab1),采用脂质体包裹电子媒介体硫堇,脂质体周围联接标记辣根过氧化物酶(HRP)的癌胚抗体(Ab2)对其传感器进行信号放大,通过循环伏安法考察了该免疫传感器的电化学特性,在优化的实验条件下,该免疫传感器的峰电流随着检测溶液中癌胚抗原(CEA)浓度的增大而增大,并在0.05～200 ng/mL CEA范围内呈现线性关系,回归方程为:Δi=0.20+0.24ρ(ng/mL);检测限为:18pg/mL(R=0.9947)。该免疫传感器可用于临床上对CEA的检测。     

基于Pt-Ni合金纳米管修饰免疫传感器的研制

利用电沉积法在聚碳酸酯(PC)喷金模板上制备了Pt-Ni合金纳米管,将甲胎蛋白抗体固定在由Pt-Ni合金纳米管修饰的玻碳电极上,研制成无电子媒介的甲胎蛋白免疫传感器。实验考察了pH值和培育时间的影响,在优化实验条件下该免疫传感器测定甲胎蛋白,甲胎蛋白浓度在20~100ng/mL的范围内有良好的线性关系,检出限为0.38ng/mL。传感器具有电流响应高、灵敏度好、性能稳定等优点。方法用于血样中甲胎蛋白的测定,获得较好结果。     

基于中性红电聚合膜的伏安型甲胎蛋白免疫传感器

用循环伏安法在玻碳电极上电聚合一层稳定的中性红聚合物膜,再通过共价键合作用将戊二醛和甲胎蛋白抗体自组装到电极表面,最后用辣根过氧化物酶封闭电极上的非特异性吸附位点,并同时起到放大响应电流信号的作用,制得高灵敏伏安型甲胎蛋白抗原免疫传感器。实验结果表明,该传感器对甲胎蛋白抗原具有良好的电流响应,该传感器的线性范围为1.00～10.0ng/mL和10.0～200ng/mL,检出限(3σ)为0.40ng/mL。     

XPS analyses on Ta/Au/NiFe/NiO/Ta films

In this study, Ta/NiFe/NiO/Ta films were prepared by magnetron sputtering. The Au layer inserted at the interface of Ta and NiFe significantly influences the exchange bias field (H_ex) of the Ta/NiFe/NiO/Ta films. The Hex of the film with 0.9 nm Au layer increased by 28% compared with that of the film without a Au layer. The results show that the Au layer inserted at the interface of Ta and NiFe segregated at the surface of the NiFe/NiO in Ta/Au/NiFe/NiO/Ta films. The Au layer insulated the direct contact and suppressed the interface reaction between the NiFe and NiO layers, thus increasing the Hex. Copyright © 2015 John Wiley & Sons, Ltd.     

sPS/PET/SsPS-H共混体系的研究

以自制间规聚苯乙烯(sPS)功能化合成的磺化间规聚苯乙烯（SsPS-H)作相容剂,研究其对sPS/PET共混物微相结构与性能的影响,发现SsPS-H能够有效地改善二者的相容性,当sPS/PET/SsPS-H为85／15／2（重量比）时,冲击强度达到11．4kJ/m^2,为纯sPS的3倍,此时材料的弯曲强度为39．1MPa,下降约8％;DMA结果表明,随SsPS-H用量的增加,共混物的Tg逐渐提高;DSC分析结果表明,共混体系中sPS的熔点不受SsPS-H含量的影响,而PET的熔点在加入6份SpPS-H时明显降低。sPS在达到最大结晶速率的温度均随SsPS-H用量的增加先提而后下降。SEM观察到加入SsPS-H后,PET分散相的尺寸减小,且均匀程度增加,共混物室温下冲击断裂显著地由脆性转变为韧性,当加入6份SsPS-H后,冲击断裂又出现脆性。     

Physico-chemical studies on thermal analyses of sodium hexa/carboxylato/ferrates/III/

Journal of Radioanalytical and Nuclear Chemistry - The thermal decomposition of sodium hexa-carboxylato/ferrates/III/ i.e. Na3[Fe/RCOO/6].xH2O /R=H, CH3, C2H5/ has been studied at various...     

Physico-chemical studies on thermal analyses of sodium hexa/carboxylato/ferrates/III/

The thermolysis of sodium hexa/benzoato/ferrate/III/, i. e. Na₃[Fe/C₆H₅COO/₆].4.5H₂O has been investigated at different temperatures in air using Mössbauer, infrared spectroscopic and derivatographic techniques /DTG, DTA, TG/. The thermal decomposition proceeds without the reduction of iron/III/. An increase in particle size of -Fe₂O₃ formed during thermolysis has been observed with increasing temperature. The end product, -NaFeO₂ is formed as a result of the solid state reaction between -Fe₂O₃ and sodium carbonate.     

Mössbauer effect studies on sodium hexa/carboxylato/ ferrates/III/

Mössbauer spectra of a series of the complexes of the type Na₃[Fe/RCOO/₆]xH₂O /R=H, CH₃, C₂H₅, C₆H₅/ has been recorded at 298±2 K. All display a quadrupole doublet with isomer shift and quadrupole splitting values in agreement with high spin iron/III/ octahedral geometry. The quadrupole splitting show an increasing trend with increasing polarizability of the substituent anion /RCOO^–/. A linear correlation between quadrupole splitting values and the /Fe–O/ stretching frequencies has also been observed.     

Tmperature programmed techniques study on the nature of the oxidant in/on V2O5catalyst ?

Summary The nature of the oxidising species in/on a vanadium pentoxide (V₂O₅) catalyst has been studied using a combination of transient techniques: (i) Temperature programmed desorption (TPD), (ii) Temperature programmed reduction (TPR), (iii) Temperature programmed oxidation (TPO) and (iv) Temperature programmed reaction (TPRn). Chemisorbed oxygen was found not to exist on a fully oxidised V₂O₅ catalyst by TPD. The TPR in CO over V₂O₅ catalyst gave three peak maxima at 930, 982 and 1043 K, indicating that three types of kinetically different oxygen states exist in/on the catalyst. Reoxidation of the CO reduced V₂O₅ catalyst by N₂O resulted in the quantitative replacement of the lattice oxygen. A further reduction of the N₂O reoxidised catalyst gave a significantly different TPR profile compared to the original material suggesting that a less crystalline material had formed. The presence of phosphorus in (VO)₂P₂O₇ was found to labilise the lattice oxygen.     

Enantioseparation/Recognition based on nano techniques/materials

Enantiomers show different behaviors in interaction with the chiral environment. Due to their identical chemical structure and their wide application in various industries, such as agriculture, medicine, pesticide, food, and so forth, their separation is of great importance. Today, the term “nano” is frequently encountered in all fields. Technology and measuring devices are moving towards miniaturization, and the usage of nanomaterials in all sectors is expanding substantially. Given that scientists have recently attempted to apply miniaturized techniques known as nano-liquid chromatography/capillary-liquid chromatography, which were originally accomplished in 1988, as well as the widespread usage of nanomaterials for chiral resolution (back in 1989), this comprehensive study was developed. Searching the terms “nano” and “enantiomer separation” on scientific websites such as Scopus, Google Scholar, and Web of Science yields articles that either use miniaturized instruments or apply nanomaterials as chiral selectors with a variety of chemical and electrochemical detection techniques, which are discussed in this article.     

/α, γ/ reaction on197Au

The excitation funcntion has been measured for the /, / reaction on¹⁹⁷Au. The nuclide produced was determination by gamma spectrometry with a Ge intrinsic detector. Irradiation was carried out in the Karlsruhe Isochronous Cyclotron with -particles of energies up to 40 MeV.     

PVC/CPE/POE热塑性弹性体特性研究

研究了氯化聚乙烯（CPE）增容PVC／POE热塑性弹性体的结构与性能,通过对比使用增容剂CPE前后体系的力学性能,确证CPE对PVC／POE体系具有良好的增容效果。用DSC,SEM对热塑性弹性体的结构特性进行了研究,采用动态硫化的方法,提高了热塑性弹性体的性能。     

Mn-Fe/Al2O3催化剂的低温脱硝性能研究

以Al_2O_3为载体,Fe、Mn为活性组分,采用浸渍法制备了Mn-Fe/Al_2O_3催化剂,研究了Mn-Fe/Al_2O_3催化剂的低温脱硝性能.实验结果表明,Fe负载量为7%时,7Fe/Al_2O_3催化剂显示出较佳的低温脱硝性能;添加Mn能明显改变7Fe/Al_2O_3催化剂低温脱硝性能,其中当Mn/Fe质量比为11∶7时,11Mn7Fe/Al_2O_3催化剂获得最佳低温脱硝效率.对催化剂的表征结果表明,比表面积和孔径的大小不是决定催化剂性能高低的主要因素;Mn O2和Fe2O3在x Mn7Fe/Al_2O_3催化剂中具有较强的相互作用,影响活性组分微观晶体结构,改善活性组分分散程度,从而提高了催化剂的低温脱硝性能;Fe的添加使催化剂表面酸性位点数目增加,从而提高7Fe/Al_2O_3催化剂的低温脱硝效率.添加Mn不仅增多了11Mn7Fe/Al_2O_3催化剂表面酸性位点数目增加,而且使催化剂表面出现新的中强性酸位点,使其低温脱硝效率进一步提高;经过详细分析,结果表明表面吸附氧Oβ、Mn4+和Fe3+的含量较高是11Mn7Fe/Al_2O_3催化剂脱硝活性较高的主要原因.