新型水溶性壳聚糖盐酸盐微球的制备与表征

以水溶性壳聚糖盐酸盐为原料,戊二醛为交联剂,采用乳化交联法制备了壳聚糖盐酸盐微球。通过多种理化手段检测及体外MG63细胞共培养对壳聚糖盐酸盐微球的形貌结构、尺寸大小、粒径分布、成球机理、结晶度、热稳定性及细胞相容性进行了测试及表征,并与普通酸溶性壳聚糖制备的微球进行比较。结果表明水溶性壳聚糖盐酸盐与戊二醛通过Schiff碱反应产生交联,易成球,球形圆整光滑;粒径分布较窄,粒径约为5～10μm;微球结晶度较低,其热稳定性较壳聚糖盐酸盐原料和酸溶性壳聚糖微球均有提高;细胞相容性良好。该微球表现出与酸溶性壳聚糖微球相似的理化性质,但因其原料为水溶性,微球制备条件更为温和,在药物载体研究领域有望得到更广泛的应用。     

Improved determination of D-glucosamine hydrochloride in health foods by HPLC using 7-fluoro-4-nitrobenzo-2-oxa-l,3-diazole as a derivative

Abstract: This article presents an improved method to detect d ‐glucosamine hydrochloride in health foods. A simple precolumn derivatization procedure with 7‐flouro‐4‐nitrobenzo‐2‐oxa‐1,3‐diazole (NBD‐F) reagent was employed. The separation of the derivatized d ‐glucosamine hydrochloride (NBD‐d ‐glucosamine hydrochloride) was performed using a mobile phase consisting of acetonitrile, potassium dihydrogen phosphate (0.01 mol/L), and trifluoroacetic acid (350:649.74:0.26, volume ratio) at a flow rate of 1.0 mL/min with the column temperature 35 °C. Under the optimum chromatographic conditions, the peak area of NBD‐d ‐glucosamine hydrochloride compared with its absolute value of the peak area of NBD‐d ‐glucosamine hydrochloride in a standard solution concentration range from 1.0 to 500.0 mg/L showed a good linear calibration (R = 0.9999). Recoveries, at spiked concentrations of 10.0, 40.0, and 500.0 mg/L, varied between 97.2% and 102.6% with relative standard deviations ranging from 0.4% to 1.5%. The present method provides sufficient sensitivity as reflected by the values of limit of detection (LOD) and limit of quantification (LOQ). LOD was determined from the signal‐to‐noise ratios (S/N) of NBD‐d ‐glucosamine hydrochloride peak of at least 3 in the recovery test at 0.02 mg/L, and the estimated LOQ was 0.06 mg/L (S/N = 10). The proposed method was successfully applicable to detect d ‐glucosamine hydrochloride in health foods and drugs containing a variety of complex materials.     

Internal reflection ellipsometry for real-time monitoring of polyelectrolyte multilayer growth onto tantalum pentoxide

Internal reflection ellipsometry was used for detection of the consecutive coating of two polyelectrolytes, poly(allylamine hydrochloride) (PAH) and poly(acrylic acid) (PAA), onto a tantalum pentoxide (Ta₂O₅) substrate until the 10th bilayer. The UV patterned PAH-PAA-multilayer was characterized in air via ellipsometry and atomic force microscopy. Suited optical models enabled the determination of the layer thicknesses in wet and dry states. Linear multilayer formation could be proved by Attenuated Total Reflection — Fourier Transformed Infrared Spectroscopy measurements following the increase of the ν(C=O) band depending on the adsorption of the PAA. Streaming potential measurements after each layer deposition step indicated a change in surface charge after each layer deposition due to the consecutive coating of PAH and PAA. In this article the internal reflection ellipsometry is shown to be a convenient possibility to analyze the modification of a thin transparent Ta₂O₅ substrate.     

盐酸胍在阻挡层化学机械抛光中对速率选择性及表面形貌的影响

We propose an alkaline barrier slurry containing guanidine hydrochloride（GH） and hydrogen peroxide.The slurry does not contain any corrosion inhibitors, such as benzotriazole（BTA）. 3-inch samples of tantalum copper and oxide were polished to observe the removal rate. The effect of GH on removal rate selectivity along withhydrogenperoxidewasinvestigatedbycomparingslurrycontainingGHandH2O2withslurrycontainingonly GH. Details about the tantalum polishing mechanism in an alkaline guanidine-based slurry and the electrochemical reactions are discussed. The results show that guanidine hydrochloride can increase the tantalum polishing rate and the selectivity of copper and barrier materials. The variation of the dishing and wire line resistance with the polishing time was measured. The dishing value after a 300 mm pattern wafer polishing suggests that the slurry has an effective performance in topography modification. The result obtained from the copper wire line resistance test reveals that the wire line in the trench has a low copper loss.     

可见光激发Bi2MoO6活化PMS降解盐酸四环素

为了利用半导体光催化和硫酸根自由基高级氧化技术协同作用处理抗生素废水,采用溶剂热法制备三维结构的钼酸铋(Bi₂MoO₆)微球,并在可见光照射下激发Bi₂MoO₆进而活化过一硫酸氢盐(PMS)处理含盐酸四环素(TC)废水。利用扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、紫外-可见漫反射光谱(UV-Vis DRS)等对样品形貌特征、晶格结构、光学性能进行表征。结果表明,Bi₂MoO₆纳米片组成的三维微球具有良好的吸附和可见光催化降解TC能力,活化PMS协同作用可以进一步提高系统降解TC的效率。通过静态实验,考察催化剂使用量、PMS初始浓度、环境共存阴离子(Cl^-、CO^2-₃、NO^-₃)和腐殖酸(HA)对可见光激发Bi₂MoO₆活化PMS降解TC性能的影响。自由基捕获实验表明,·OH、SO^-₄·、O^-₂·和h⁺等活性基团在可见光激发Bi₂MoO₆活化PMS催化降解TC过程中都做出了贡献。     

氨基葡萄糖盐酸盐稳定性及其制备的研究

测定了Ｄ－氨基葡萄糖盐酸盐在酸液中的溶解度及在加热条件下其稳定性，探讨了甲壳素酸水解和甲壳素质量与产品质量、收率之间的关系，对工业化生产Ｄ－氨基葡萄糖盐酸盐的工艺条件优化、质量和收率的提高具有指导意义。     

黄连素对油脂抗氧化作用的研究

以稀硫酸水溶液作溶剂,采用浸渍法从黄连中提取黄连素。利用SCHALL烘箱法,通过测定丙二醛吸光度值和过氧化值来评价黄连素、以及黄连素与其它抗氧化剂复配后对油脂的抗氧化效果。结果表明,黄连素对油脂有抗氧化作用,而且具有计量效应关系;柠檬酸、酒石酸、茶多酚对黄连素的抗氧化作用均有协同增效作用。     

盐酸乙脒合成的工艺改进

介绍了盐酸乙脒合成的工艺改进，与传统工艺比较，该工艺能耗低，收率高，经济效益高，是最理想的生产工艺。     

Complexation of poly-2,5-dimethyl-4-vinylethynilpyperidol-4 hydrochloride with transition metal ions in solution

The interaction of transition metal ions with poly-2,5-dimethyl-4-vinylethynilpyperidol-4 hydrochloride in solution have been investigated potentiometrically, spectroscopically and viscometrically. influence of ionic strength, composition of solvent and various metal ions nature on the viscosity of polyelectrolyte-metal complexes are discussed.     

Characterization of Transdermal Delivery of Nefopam Hydrochloride under Iontophoresis

In vitro iontophoretic delivery of nefopam hydrochloride was conducted to study the effects initial drug concentration, pH, ionic strength and viscosity of the donor solutions on the transdermal flux through a hairless mouse skin. Stability of nefopam hydrochloride under the experimental conditions was investigated. Type of electrode, current intensity, electric voltage and electrode distance were evaluated. Appropriate conditions were selected to minimize the potential degradation problems of nefopam hydrochloride during iontophoresis. Results show that the silver/silver chloride electrode provides better drug stability than the platinum electrode. Higher current intensity resulted in faster transdermal flux and therefore better drug permeability. The increase in the drug permeability appears to be proportionally increased as the current intensity increases in the range of 0.253 to 1.265 mA/cm². The iontophoretic transdermal delivery of nefopam hydrochloride was observed to increase as the drug concentration in the donor site was increased until it's close to the equilibrium concentration. The optimum pH to achieve the best iontophoresis under constant current was determined to be at pH 3.0. This may be due to the highest available charge density of nefopam was achieved at this pH to provide the best conductance. A decrease in the iontophoretic transdermal flux was encountered as an increase in the solution ionic strength due to the increased competition of similar charged ions with the available current. The increase in the donor solution viscosity decreased the conductivity of the ions and hindered the trandermal flux of the drug under iontophoresis.