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DrugFET的研究(Ⅳ).硅钨酸—麻黄碱FET的研制与应用 总被引:5,自引:0,他引:5
将离子敏感场效应晶体管与药物敏感膜相结合研制成一种对盐酸麻黄碱有良好响应的药物敏感场效应晶体管传感器。 相似文献
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《Arabian Journal of Chemistry》2020,13(12):8848-8887
Phthalocyanine (Pc) complexes are an important class of dyes with numerous (e.g., biological, photophysical, and analytical) applications. Among the methods used to improve the properties of these complexes, one should mention the introduction of different substituents, variation of the central metal ion, ligand exchange, and conjugation to nanomaterials (e.g., carbon-based nanomaterials and metal nanoparticles (NPs)). This work briefly reviews Pc complex conjugation to Ag and Au NPs, highlights the different NP shapes, and discusses the diversity of conjugation approaches. Moreover, the use of UV–Vis spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, atomic force microscopy, dynamic light scattering and Fourier transform infrared spectroscopy to characterize Pc-NP hybrids is summarized. The effect of conjugation on Pc photo-physicochemical properties (fluorescence, singlet oxygen generation, triplet state formation, and optical limiting behavior) is discussed, and future perspectives for the synthesis and applications of new hybrids are provided. 相似文献
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Summary In the aqueous solutions of poly(N-vinylacetamide) in the presence of Na2SO4 or (NH4)2SO4, the intrinsic viscosities were small and the Huggins constants were large compared with those in water. Similar but much
less effects were observed for NaF. Opposite effects were found, however, for NaSCN. The poor solvent quality of aqueous sulfate
solutions was significantly improved by the addition of guanidine hydrochloride to 3 M or higher. Urea was much less effective
in improving the solvent quality. The different M28.8neffects observed between urea and GdnHCl may be explained by their different
binding affinities to amide group. Solubilization of PNVA flocculates induced by the presence of 0.8 M Na2SO4 took place by adding urea to 1 M, although only small changes were detected in the viscosity behavior accompanying the addition
of 1 M urea.
Received: 12 June 1997 Accepted: 4 August 1997 相似文献
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Spectrophotometric methods for the determination of labetalol hydrochloride in pure and dosage forms
Simple and sensitive Spectrophotometric methods for the determination of labetalol hydrochloride are described. The first two are based on the oxidative coupling reaction of labetalol hydrochloride withp-N,N-dimethyl-phenylenediamine dihydrochloride (method A, max 685 nm) and 3-methyl-2-benzothiazolinone hydrazone hydrochloride (method B, max 545 nm) in the presence of sodium hypochlorite and eerie ammonium sulphate as oxidants, respectively. The third depends on the formation of an ion-association complex of labetalol hydrochloride with suprachen violet 3B at pH 1.3, which is extracted into chloroform (method C, max 565 nm). The methods obey Beer's law and the precision and accuracy of the methods were checked against the B.P. reference method and the relative standard deviations were in the range 0.35–0.52%. These methods are applied to the determination of labetalol in dosage forms. 相似文献
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盐酸环丙沙星及其制剂含量测定方法的探讨 总被引:1,自引:0,他引:1
非水滴定法测定盐酸环丙沙星的含量时,需要预先加入冰乙酸和乙酸汞进行转化处理,两种试剂的加入顺序对盐酸环丙沙星的溶解速度影响较大,先加入乙酸汞时,盐酸环丙沙星溶解较快。用高效液相色谱法测定盐酸环丙沙星片及盐酸环丙沙星胶囊的含量时,如果以水作溶剂,测定值明显偏低,宜改用0.l mol/L盐酸溶液作溶剂。 相似文献
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Taha EA 《Analytical and bioanalytical chemistry》2003,376(7):1131-1136
Two simple and sensitive kinetic methods for the determination of dothiepin hydrochloride are described. The first method is based on kinetic investigation of the oxidation reaction of the drug with alkaline potassium permanganate at room temperature for a fixed time of 25 min. The absorbance of the colored manganate ions is measured at 610 nm. The second method is based on the reaction of dothiepin hydrochloride with 4-chloro-7-nitrobenzofurazan (NBD-Cl) in the presence of 0.1 mol L–1 sodium bicarbonate. Spectrophotometric measurement was achieved by recording the absorbance at 470 nm for a fixed time of 60 min. All variables affecting the development of the color were investigated and the conditions were optimized. Plots of absorbance against concentration in both procedures were rectilinear over the ranges 4–24 and 50–250 g mL–1, with mean recoveries 99.33±0.42 and 99.88±0.53, respectively. The proposed methods were successfully applied for the determination of dothiepin hydrochloride in bulk powder and in capsule dosage form. The results obtained were found to agree statistically with those given by the non-aqueous B.P. method. Furthermore the methods were validated according to USP guidelines and also assessed by applying the standard addition technique. The determination of dothiepin hydrochloride by the fixed concentration method is feasible with the calibration equations obtained, but the fixed time method proves to be more applicable. 相似文献