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71.
Chengchao Chu Long Li Shuai Li Meng Li Shenguang Ge Jinghua Yu Mei Yan Xianrang Song 《Mikrochimica acta》2013,180(15-16):1509-1516
We report on an ultrasensitive fluorescence immunoassay for human chorionic gonadotrophin antigen (hCG). It is based on the use of silica nanoparticles coated with a copolymer (prepared from a fluorene, a phenylenediamine, and divinylbenzene; PF@SiO2) that acts as a fluorescent label for the secondary monoclonal antibody to β-hCG antigen. In parallel, Fe3O4 nanoparticles were coated with polyaniline, and these magnetic particles (Fe3O4@PANI) served as a solid support for the primary monoclonal antibody to β-hCG antigen. The PF@SiO2 exhibited strong fluorescence and good dispersibility in water. A fluorescence sandwich immunoassay was developed that enables hCG concentrations to be determined in the 0.01–100 ng·mL?1 concentration range, with a detection limit of 3 pg·mL?1. Figure
Fluorescence detection of prepared immune reagent nano-composites using the fluorescence cell 相似文献
72.
A thin film of poly(eriochrome black T) was deposited on the surface of glassy carbon electrode by cyclic voltammetry, and this system is shown to enable the sensitive determination of adenine (A) and guanine (G). Scanning electron microscopy, Fourier transform infrared spectroscopy and electrochemical impedance spectroscopy were carried out to characterize the film which exhibits excellent electrocatalytic activity toward the oxidation of A and G in 0.1 M phosphate buffer solution (pH 4.0). Square wave voltammetry reveals an oxidation peak at 1084 mV whose current is linearly related to the concentration of A in the range from 0.05 to 1.00 μM. The oxidation peak for G occurs at 788 mV, and its current is linearly related to the concentration of G in the range from 0.025 to 1.00 μM. The detection limits are 0.017 μM for A and 0.008 μM for G (at S/N?=?3), respectively. The modified electrode displays good reproducibility and selectivity for the determination of A and G. The sensor was applied to quantify A and G in fish sperm DNA with satisfactory results. Figure
Square wave voltammograms of bare GCE (a), PEBT/GCE (b) in the presence of 1.00 μM adenine (A) and 1.00 μM guanine (G). 相似文献
73.
74.
本文制备了三种在1,4-bis[2-(4-pyridyl)ethenyl]-benzene(bp-eb)上接枝不同烷基链长度的热致变色材料DC8、DC12、DC16. 在365 nm激发光下,随着温度升高,它们呈现出荧光颜色的改变,这种改变来自于晶体态与无定形态之间的转变. 此外,DC16也呈现出光致变色的性质. 通过差示扫描量热法测试得到的相转变温度高于实验过程中荧光颜色改变时的温度. 因此,这种变色行为来自于光与热共同作用的结果. 乙醇可以使粉末变回起始的晶体状态,从而使荧光颜色恢复,实现热致变色行为的可逆. 本研究对理解热致变色分子的结构-性质关系,指导热致变色分子设计具有重要意义. 相似文献
75.
Chao Liu Liying Wang Lin Yang Famei Wang Chunhong Xu Jingwei Lv Guanglai Fu Xianli Li Qiang Liu Haiwei Mu Tao Sun Paul K. Chu 《Physics letters. A》2019,383(25):3200-3206
A single-polarization filter comprising a gold-coated photonic crystal fiber based on surface plasmon resonance is designed and investigated. The pattern matching and coupled polarization characteristics analyzed by the full-vector finite element method (FEM) and losses at 1,540 nm are achieved to 1,016.01739 dB/cm (x-pol core mode) and 33.81917 dB/cm (y-pol core mode). The crosstalk (CT) value of the 1,540 nm band is ?853.12653 dB for fiber length and the bandwidth is 850 nm. The working wavelength of the filter ranges from 1,280 nm to 1,540 nm by varying the diameter of outer air holes (), the diameter of inner air holes (), the metal film thickness (t), as well as the liquid refractive index (n). 相似文献
76.
Jing Wu Ying Qu Kun Shi Bingyang Chu Yanpeng Jia Xue Xiao Qianjun He Zhiyong Qian 《中国化学快报》2018,29(12):1819-1823
The CPT was loaded into the HMSNs with the high loading capacity. Then the CPT@HMSNs were loaded into the PLEL thermosensitive hydrogels for local therapy to prevent the recurrence of breast cancer after the tumor was resected. 相似文献
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79.
Yang‐Chu Lin Kung‐Lung Cheng Woan‐Shiow Tzeng Chih‐Lin Su Long‐Je Lee Ling‐Yung Wang 《Liquid crystals》2013,40(3):289-293
A series of N,N‐disubstituted‐4‐[(4‐aminophenyl)diazenyl]benzylidene‐4′‐alkylanilines (azo dyes) were synthesized from the reaction of the corresponding benzaldehyde with alkylanilines. These azo dyes exhibit nematic and SmC phases on heating. Their order parameter, photo‐stability and miscibility were studied by investigation of a representative sample. 相似文献
80.
In this article, we deal with the notion of the envelopes of homotopies which is the generalized version of functional envelopes in discrete dynamical systems. We prove the stability for envelopes of homotopies in complete normed algebra and we get the stabilities of the derivation and the extended derivation for the notion in the spaces. 相似文献