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991.
Sensitive Electrochemical Prostate Specific Antigen Aptasensor: Effect of Carboxylic Acid Functionalized Carbon Nanotube and Glutaraldehyde Linker 下载免费PDF全文
The performance of carboxylic acid functionalized carbon nanotubes (CNTs(COOH)), chitosan (Chit), carbon nanotubes‐chitosan (CNTs‐Chit and CNTs(COOH)‐Chit) for immobilizing of amino‐functionalized ssDNA and fabrication of electrochemical prostate specific antigen (PSA) aptasensor were studied in detail using X‐ray diffraction spectroscopy (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT‐IR) and electrochemical impedance spectroscopy (EIS). The assemblies of capture probe are formed on the surface via two approaches: EDC/NHS chemistry and glutaraldehyde linker. Cyclic voltammetry (CV), differential pulse voltammetry (DPV) and EIS techniques were used to investigate the analytical performance of the PSA aptasensor. Under optimum conditions the sensitivity of 0.0026 µA/(ng/ml) and a limit of detection of 0.75 ng/ml (22 pM) were obtained for PSA detection. This protocol offers a new means for sensitive detection of PSA with some advantages in terms of simplicity, selectivity, ease of use and regenerability. 相似文献
992.
993.
《Magnetic resonance in chemistry : MRC》2002,40(3):231-236
The assignments of 1H and 13C NMR chemical shifts together with x‐ray diffraction data for synthesized diosgenyl 3,4,6‐tri‐O‐acetyl‐2‐deoxy‐2‐tetrachlorophthalimido‐β‐D ‐glucopyranoside are described. The structure of this glycoside was established by using homo‐ and heteronuclear two‐dimensional NMR techniques. X‐ray diffraction data for this compound are also reported. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
994.
The title compound (Mr = 373) crystalizes in the othorhombic space group P bna with a = 10.410(2), b = 11.658(4), c = 23.108(3) Å, V = 2804.4 Å Z = 8. The single crystal intensity data were collected using MoK∞ radiation (λ = 0.7093Å) at room temperature. The crystal and molecular structure was solved with the final agreement index R = 0.039 for 1046 observed reflections. The bond lengths N(1)- C(7) and C(7)-C(8) of the title compound are slightly longer than those of 3-substituted sydnone derivatives. This may be attributed to the steric effect arising from the interaction of the phenyl ring and the 4-substituent with the neighboring atoms of sydnone ring. Both the title compound and 4-acetyl-3-(p-tolyl)sydnone have smaller dihedral angles between the sydnone ring and the plane of the sp2 orbital of the double bond of the 4-substituent and both have shorter C(7)-C(9) bond lengths than those of other similar sydnone derivatives. 相似文献
995.
《Journal of Chemical Sciences》2007,119(4):283-288
In this paper, the preparations and voltammetric characteristics of chitosan-modified glassy carbon (Ct-MGC) and platinum
electrodes are studied. Ct-MGC can be used for pre-concentration and quantification of trace amounts of platinum in solution.
At low pH medium, the complex of Pt with protonated group-NH3+ in the chitosan molecule has been confirmed by FT-IR spectra studies. 相似文献
996.
997.
壳聚糖对Cd2+的吸附性能 总被引:4,自引:0,他引:4
壳聚糖(chitosan,简称CTS)是由虾、蟹壳脱钙、蛋白质和脂肪后、经化学改性得到的天然高分子聚合物,分子中存在能与金属离子配位的羟基或氨基,其配合物可作为絮凝剂和螯合吸附剂用于水处理[1 3]及湿法冶金[4]等。本文考察了壳聚糖对Cd2+的静态吸附性能。1 实验部分1.1 试剂与仪器壳聚糖(浙江玉环县化工厂);硫酸镉、硝酸镉(分析纯,广州化学试剂厂);碳酸镉(化学纯,上海试剂二厂),其余试剂均为分析纯。78 1型磁力加热搅拌器(江苏金坛市恒丰仪器厂),501型超级恒温器(上海实验仪器厂),pHS 3型酸度计(上海第二分析仪器厂)。1… 相似文献
998.
A novel boronated aminocyclobutanecarboxylic acid was synthesized in 10 steps for potential use in neutron capture therapy. The molecule was modeled after the unnatural amino acid 1-aminocyclobutanecarboxylic acid, which has shown high uptake in brain tumors. 相似文献
999.
XU Xing-Ling TANG Zong-Xun GUO Zhi-Zheng CHEN Yun-ShengDepartment of Chemistry Northwest University Xi''''an Shanxi ChinaSHI Ni-Cheng MA Zhe-Sheng China University of Geoscience Beijin ChinaHAN Yu-Zhen Department of Chemistry Beijin University Beijin China 《中国化学》1995,(1)
Based on the phase equilibrium study of the system Sm(ClO4)3-4-monochloroace-tylantipyrine (C13H13ClN2O2)-H2O at 30℃, we have synthesized the title complex [Sm(C13H13Cl. N2O2)3(H2O)4](C1O4)3.4H2O. The single crystal structure analysis on RASA-IIS Rigaku diffrac-tometer shows that the coordination number of the metal ion is nine and the geometry of the complex is tricapped trigonal prism. Two of the three molecules of organic ligand act as bidentate chelated through both carbonyl oxygens to the metal ion, but the other one as a monodentate coordinated only through the ring carbonyl oxygen, the side chain carbonyl is far away from the central ion. The crystal is monoclinic, space group P21, a = 18.013(4), 6 = 14.709(3), c = 10.536(3) A, β=94.69(2)°, V=2782(1) A3, Z=2. 相似文献
1000.
本文利用Dini右上、右下导数给出了非光滑伪线性多目标规划的对偶理论,建立了Mond-Weir型对仍与Wolf型对偶;并证明了原问题与对偶问题之间的对偶定理. 相似文献