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51.
A background-free, fast protein staining method in polyacrylamide gel electrophoresis using an acidic dye, zincon (ZC) and a basic dye, ethyl violet (EV) is described. It is based on the counterion dye staining technique that employs two oppositely charged dyes to form an ion-pair complex in staining solution. The selective binding of free dye molecules to proteins in acidic solution produces bluish violet-colored bands. It is a rapid and end-point staining procedure, involving only fixing and staining steps that are completed in 1-1.5 h. The detection limit of this method is 8-15 ng of protein that is comparable to the sensitivity of the colloidal Coomassie Brilliant Blue G (CBBG) stain. Due to its sensitivity and speed, this stain may be more practical than any other dye-based stains for routine laboratory purposes. 相似文献
52.
A glucose biosensor with enzyme immobilised by sol–gel technology was constructed and evaluated. The glucose biosensor reported is based on encapsulated GOX within a sol–gel glass, prepared with 3-aminopropyltriethoxy silane, 2-(3,4-epoxycyclohexyl)-ethyltrimetoxy silane and HCl. A flow system incorporating the amperometric biosensor constructed was developed for the determination of glucose in the 1×10−4–5×10−3 mol l−1 range with a precision of 1.5%. The results obtained for the analysis of electrolytic solution for iv administration and human serum samples showed good agreement between the proposed method and the reference procedure, with relative error <5%. 相似文献
53.
Mariko Kusabe Hiromitsu Kozuka Satoru Abe Hiroshi Suzuki 《Journal of Sol-Gel Science and Technology》2007,44(2):111-118
Hydroxypropylcellulose (HPC)–titania hybrid thin films were prepared by sol–gel method where titanium tetraisopropoxide Ti(OC3H7
i
)4 was hydrolyzed under acidic conditions in the presence of HPC, followed by dip-coating and drying at 120 °C for 24 h. The
viscosity average molecular weight of HPC was 55,000–70,000 or 110,000–150,000, and the TiO2/(HPC + TiO2) mass ratio ranged from 0 to 1, which was calculated on the assumption that all Ti(OC3H7
i
)4 is converted into TiO2. The films were 0.35–1.0 μm thick, transparent in visible region and opaque in ultraviolet (UV) region, where the optical
absorption coefficient in UV region increased with increasing titania content. The refractive index increased with increasing
titania content, ranging from 1.6 to 1.8 for the hybrid thin films. The pencil hardness increased from 6B to 5H, the durability
in hot water significantly increased and the contact angle of water on films increased from 35° to 89° with increasing titania
content. Crack-free films could be deposited on organic polymer substrates irrespective of titania or HPC contents, where
cracking did not occur at higher HPC contents even when the substrate was bent. 相似文献
54.
J. Thomas 《Chromatographia》1984,18(3):149-152
Summary The TLC behaviour of N-phenyl-1,2,4-triazoles and their derivatives on silica gel plates has been studied using simple solvents. Isomers were very well distinguished, resulting from different activities due to hydrogen bonding. A mixture of seven compounds has been resolved with diethylether-n-butylamine-pyridine (91.4:7.7:0.9). 相似文献
55.
制备和表征了一种新的酞菁键合硅胶,三-β-(辛巯基)-β-(磺酰胺基)-酞菁铜键合硅胶。研究了该键合酞菁硅胶作为HPLC固定相的基本色谱性能。实验结果表明,该固定相可以分离四-α-(2,2,4-三甲基-3-戊氧基)酞菁(铜、镍)的4种异构体,也可以观察到四-α-(2,2,4-三甲基-3-戊氧基)无金属酞菁的4种异构体,而商业C18(VERTEX Eurospher)却只能观察到两组峰,表明这种酞菁键合硅胶固定相在分析、分离一些取代酞菁异构体方面比商业C18具有更好的分离效果。 相似文献
56.
Urška L. Štangar Urh Černigoj Polonca Trebše Ksenija Maver Silvia Gross 《Monatshefte für Chemie / Chemical Monthly》2006,137(5):647-655
Summary. Transparent TiO2 films with a high photodegradation activity towards an azo dye in aqueous solution were prepared by sol–gel processing. Films
on soda–lime glass supports protected with a thin silica barrier layer exhibited better crystallization and monodisperse nanoparticles,
higher absorption of light below 370 nm, and higher photocatalytic activity than those films deposited on bare glass supports
proving the detrimental effect of interdiffused sodium ions on the development of the anatase nanostructure. The effect of
substrate was more pronounced in thinner films (300 nm) than in thicker ones (1200 nm), which were achieved by adding a template
(i.e. Pluronic F127) to the sol. 相似文献
57.
改进黏度在线凝胶色谱的测定结果 总被引:2,自引:0,他引:2
郭明海 《分析测试技术与仪器》2003,9(4):240-243
黏度在线凝胶色谱是一种同时配备浓度和黏度检测器的凝胶色谱,由于其测定过程简单直接,被越来越多地广泛采用,但因为数据处理方式和仪器精度的问题,其数均分子量、重均分子量与分散度结果存在较大误差.实验表明,选择适当的谱峰叠加处理、改进普适校正曲线精度、调整标样进样方式以及选择合适的积分点等手段可以明显改善存在的问题,从而大幅度地提高数均分子量、重均分子量与分散度的结果准确性。 相似文献
58.
Maria Rosaria Acocella 《Tetrahedron letters》2005,46(36):6141-6144
The vinylogous aldol reaction of O-silyl dienolates deriving from 2,2-dimethyl-[1,3]-dioxin-4-ones proceeds in moderate to excellent yields in the presence of catalytic amounts of PhCOOH under solvent-free conditions. Modest to good yields can be obtained by using silica gel or 3 Å molecular sieves as heterogeneous catalysts. 相似文献
59.
Through the sol–gel process, using the so-called neutral amine route, spherical particles of 1:1 zirconia–titania were synthesized from zirconium(IV) and titanium(IV) butoxides as well as 1,12-diaminododecane as precursor species. The obtained product exhibited a hexagonal structure, as determinated by X-ray diffraction data. The obtained material was also characterized by thermogravimetry, differential scanning calorimetry, infrared spectroscopy, scanning electron microscopy, and surface area measurements. Despite the release of template molecules on heating, the spherical morphology was retained up to about 1200°C, at which the disruption of the spheres took place. 相似文献
60.
A star network polymer with a pentaerythritol core linking four PEG-block polymeric arms was synthesized, and its corresponding gel polymer electrolyte based on lithium perchlorate and plasticizers EC/PC with the character being colorless and highly transparent has been also prepared. The polymer host was characterized and confirmed to be of a star network and an amorphous structure by FTIR, ^1H NMR and XRD studies. The polymer host hold good mechanical properties for pentaerythritol cross-linking. Maximum ionic conductivity of the prepared polymer electrolyte has reached 8.83 × 10 ^-4 S·cm^-1 at room temperature. Thermogravimetry (TG) of the polymer electrolyte showed that the thermal stability was up to at least 150 ℃. The gel polymer electrolyte was further evaluated in electrochromic devices fabricated by transparent PET-ITO and electrochromically active viologen derivative films, and its excellent performance promised the usage of the gel polymer electrolyte as ionic conductor material in electrochrornic devices. 相似文献