Separation and detection of chlorpromazine hydrochloride and promethazine hydrochloride using electrochemiluminescence followed by capillary electrophoresis

Phenothiazine drugs, chlorpromazine hydrochloride (CPZ) and promethazine hydrochloride (PMZ), were determined with Ru(bpy)(3)(2+) electrochemiluminescene by the capillary electrophoresis (CE-ECL). It was found that both CPZ and PMZ could produce an intermediate that acted as coreactants to react with Ru(bpy)(3)(2+) to produce excited states which were capable of emitting light. This CE-ECL detection method had high sensitivity, good selectivity and reproducibility for CPZ and PMZ determination.

The release behavior of doxorubicin hydrochloride from medicated fibers prepared by emulsion-electrospinning

The release behavior of a water-soluble small molecule drug from the drug-loaded nanofibers prepared by emulsion-electrospinning was investigated. Doxorubicin hydrochloride (Dox), a water-soluble anticancer agent, was used as the model drug. The laser scanning confocal microscopic images indicated that the drug was well incorporated into amphiphilic poly(ethylene glycol)-poly(L-lactic acid) (PEG-PLA) diblock copolymer nanofibers, forming "core-sheath" structured drug-loaded nanofibers.

Enantioseparation of Dioxopromethazine Hydrochloride in Urine with Liquid-Liquid Extraction by CE-ECL Detection

Capillary electrophoresis coupled with electrochemiluminescence detection was developed for the separation and determination of dioxopromethazine hydrochloride (DPZ) enantiomers. Performance parameters of the proposed method were evaluated. An improved separation of DPZ enantiomers could be achieved after adding boric acid to buffer. The enantiomers were completely separated with running buffer of 16.5 mM beta-CD in 25 mM tris-H3PO4-40 mM H3BO3 at pH 2.5. The proposed method was successfully applied to the separation and determination of DPZ enantiomers in human urine with a liquid-liquid extraction procedure.

Ultrafine PEG-PLA fibers loaded with both paclitaxel and doxorubicin hydrochloride and their in vitro cytotoxicity

By means of "emulsion-electrospinning", both hydrophobic and hydrophilic drugs, paclitaxel (PTX) and doxorubicin hydrochloride (DOX), were successfully loaded into PEG-PLA nanofiber mats to realize multi-drug delivery. The release behaviors of both the drugs from the same fiber mats were ascribed to their solubility properties and distribution status in the fibers. Due to its high hydrophilicity, DOX was easy to diffuse out from the fibers, and its release rate was always faster than that of hydrophobic PTX. Moreover, the release rate of PTX was accelerated by DOX's release from the same drug-loaded fibers. In vitro cytotoxicity against rat Glioma C6 cells indicated that the dual drug combination showed a higher inhibition and apoptosis against C6 cells than a single drug-loaded system, which suggests the promise for multi-drug delivery on combination therapy.

Determination of benzhexol hydrochloride by capillary zone electrophoresis with an end-column electrochemiluminescence detection

A capillary zone electrophoresis with end-column electrochemiluminescence (ECL) detector was described for the determination of benzhexol hydrochloride. The detection was based on the tris(2,2'-bypyridine)ruthenium(II) [Ru(bpy)(3)(2+)] ECL reaction with the analyte. Electrophoresis was performed using a 25 mum i.d. uncoated capillary. 10 mM sodium phosphate buffer (pH=8.0) was used as the running buffer. The solution in the detection cell was 80 mM sodium phosphate (pH=8.0) and 5 mM)21 Ru(bpy)(3)(2+). A linear calibration curve of three-orders of magnitude was obtained (with a correlation coefficient of > 0.999) from 1.0X10(-8) to 1.0X10(-5) M and the limit of detection was 6.7 X 10(-9) M (S/N= 3). This just provides an easy and sensitive method to determine the active ingredient in pharmaceutical formulations.

Study on charge transfer reactions at multilayers of polyoxometalates clusters and poly(allylamine hydrochloride) (Grotthuss-018)

Multilayers of anionic phosphotungstic acid (PTA) clusters and positively charged protonated poly(allylamine hydrochloride) (PAH) were assembled by layer-by-layer self-assembled method on Au electrode modified by 3-mercaptopropionic acid (3-MPA). The effect of the charge of the surface of the multilayer assembly on the kinetics of the charge transfer reaction was studied by using the redox probes [Fe(CN)(6)](3-)/(4-) [Ru(NH3)(6)](2+/3+). The cyclic voltammetry experiments showed that the peak currents and peak-to-peak potential differences changed after assembling different layers on the electrode surface indicating that the charge of the surface has a significant effect on the kinetics of the studied charge transfer reactions. These reactions were studied in more detail by electrochemical impedance spectroscopy. When [Fe(CN)(6)](3-/-) was used as the redox label, multilayers that terminated with negatively charged PTA showed a high charge transfer resistance but multilayers that terminated with positively charged PAH showed lower charge transfer resistance. With [Ru(NH3)(6)](2+/3+) as the redox label, the charge transfer resistance at multilayers that terminated with positively charged PAH was much higher than at the multilayer terminated by the negatively charged PTA.

Layer-by-layer multilayer films self-assembled from a rare-earth-containing poly-oxometalate Na-9[Eu(W5O18)(2)] and poly (allylamine hydrochloride) and their photoluminescent properties

Ultrathin multilayer films of a rare-earth-containing polyoxometalate Na-9[Eu(W5O18)(2)] (EW) and Poly (allyamine hydrochloride) (PAH) have been prepared by layer-by-layer self-assembly from dilute aqueous solutions. The fabrication process of the EW/PAH multilayer films was followed by UV-vis spectroscopy and ellipsometry, which show that the deposition process is linear and highly reproducible from layer to layer. An average EW/PAH bilayer thickness of ca. 2.1 nm was determine,by ellipsometry. In addition, the scanning electron microscopy (SEM) image of the EW/PAH film indicates that the film sufface is relatively uniform and smooth. The photoluminescent properties of these films were also investigated by fluoresence spectroscopy.

Photoluminescent organic-inorganic composite films layer-by-layer self-assembled from the rare-earth-containing polyoxometalate Na-9[EuW10O36] and poly(allylamine hydrochloride)

Photoluminescent organic-inorganic composite films incorporating the rare-earth-containing polyoxometalate Na-9[EuW10O36] (EW) and poly(allylamine hydrochloride) (PAH) have been prepared by the layer-by-layer self-assembly method. UV-vis spectroscopy and ellipsometry were used to follow the fabrication process of the EW/PAH composite films. The experimental results show that the deposition process is linear and highly reproducible from layer to layer. An average EW/PAH bilayer thickness of ca. 2.1 nm was determined by ellipsometry. In addition, scanning electron microscopy and atomic force microscopy images of the EW/PAH composite films indicate that the film surface is relatively uniform and smooth. The photoluminescent properties of these films were investigated by fluorescence spectroscopy.

The antioxidant activity of glucosamine hydrochloride in vitro

The antioxidant potency of chitin derivative-glucosamine hydrochloride was investigated employing various established in vitro systems. Such as superoxide (O-2(center dot-))/hydroxyl ((OH)-O-center dot)-radical scavenging, reducing power, and ferrous ion chelating potency. As expected, we obtained several satisfying results, its follows: first, glucosamine hydrochloride had pronounced scavenging effect on superoxide radical. For example, the O-2(center dot-) scavenging activity of glucosamine hydrochloride was 83.74 parts per thousand at 0.8 mg/mL. Second, the (OH)-O-center dot scavenging activity of glucosamine hydrochloride was also strong and was about 54.89% at 3.2 mg/mL. Third, the reducing power of glucosamine hydrochloride was more pronounced. The reducing power of glucosamine hydrochloride was 0.632 at 0.75 mg/mL. However, ferrous ion-chelating potency was soft. Furthermore, ferrous ion-chelating potency, the scavenging rate of radical, and the reducing power of glucosamine hydrochloride increased with their increasing concentration, and they were concentration dependent. The multiple antioxidant activity of glucosamine hydrochloride was evident as it showed considerable reducing power, superoxide/hydroxyl-radical scavenging ability. These in vitro results suggest the possibility that glucosamille hydrochloride could be effectively employed its an ingredient in health or functional food, to alleviate oxidative stress. (c) 2005 Elsevier Ltd. All rights reserved.

First example of asymmetric transfer hydrogenation in water induced by a chiral amino alcohol hydrochloride

The low-cost and commercially available (-)-ephedrine hydrochloride was firstly employed in the [RuCl2(1)-cymene)](2)-catalyzed asymmetric transfer hydrogenation of prochiral ketones in water. The reaction could be performed in the open air at rt, affording excellent yields (up to 99%) and good enantioselectivities (up to 83% ee). It provided a further step toward the discovery of simplified catalyst systems for eventual availability. (c) 2005 Published by Elsevier Ltd.

理化因子诱导的CP43和CP47结构与功能变化规律的研究

CP43和CP47是PSII中位于类囊体膜上的两种内周天线色素蛋白复合体，它们都是由六个跨膜的α-螺旋和五个膜外环组成。CP43和CP47的主要功能是把光系统II(PSII)外周天线色素蛋白复合体(LHCII)吸收的能量传给反应中心(RC)，从而引起光化学反应。因此，研究CP43和CP47的结构与功能对于揭示植物光合作用高效吸能、传能的分子机理具有重要意义。由于CP43和CP47的分离纯化比较困难，所以相对于其它的光合膜蛋白来说，人们对CP43和CP47的研究比较少。在本文中，我们在分离、纯化CP43和CP47的基础上，采用多种光谱学和波谱学技术对CP43和CP47在GuHCl和高温作用下的变性过程及其结构与功能的变化规律进行了比较深入的研究，获得了如下结果： 1. CP43和CP47膜外区的结构特点及盐酸胍(GuHCl)引起的变性研究 我们用荧光光谱、园二色(CD)光谱研究了GuHCl引起CP43和CP47的变性过程及其膜外区的结构特点。研究发现：CP43和CP47的膜外区具有一定的有序结构，而不是一种没有规则的伸展状态;和CP43相比，CP47的三级结构及Chl a的微环境对GuHCl更敏感。在GuHCl作用下，从β-Car到Chl a的能量传递变化和三级结构的变化密切相关，而与二级结构变化的相关性则较小;和大多数水溶性蛋白不一样，CP43和CP47对GuHCl变性有一定的抵抗力，而且其变性过程不表现为二态过程，这些都是膜蛋白的特点。 2 CP43和CP47中与芳香族氨基酸有关的能量传递研究 我们用吸收光谱、荧光光谱并参照PSII的3.5 Å的晶体结构分析结果研究了CP43和CP47中与芳香族氨基酸有关的能量传递。发现：和水溶性蛋白不一样，CP43和CP47中的酪氨酸(Tyrs)并不能有效的把其能量传给色氨酸(Trps);CP43和CP47中的芳香族氨基酸能通过Föster机制和Dexter机制把其能量传给Chl a，并且CP47中的传递效率要大于CP43;在CP47中Föster机制是芳香族氨基酸和Chl a之间能量传递的主要方式，而在CP43中Dexter机制则是主要方式。这些结果也暗示了，太阳光中的紫外辐射对植物来说除了其伤害作用以外也有一定的益处。 3 GuHCl诱导CP43和CP47变性的太赫兹（THz）光谱研究 THz时域光谱技术(THz-TDS)是研究分子构型状态的一个新工具。近年来，已被应用于物理或化学分子的研究中。我们首次把这个技术应用到光合膜蛋白CP43和CP47的GuHCl变性研究上。研究发现，在小于1.5 THz时，THz吸收光谱强度随着频率的增加而增加可以看作是蛋白质变性的标志。在GuHCl作用下频域光谱中出现的1.8 THz峰应来源于Chl a和GuHCl之间的相互作用。实验结果表明，THz光谱是区分蛋白分子的不同构型状态以及监测蛋白变性过程的有力工具。 4 CP43热变性的傅立叶变换红外光谱和THz光谱研究 我们用傅立叶变换红外光谱技术(FT-IR)、SDS聚丙稀凝胶电泳(SDS-PAGE)和THz光谱技术对CP43的热变性过程进行了研究。结果表明，在高温处理下，CP43的二级结构发生了变化，且其跃变点发生在59℃。随着温度的逐渐升高，CP43先发生凝集，接着又发生降解;CP43的低频振动模随着温度的升高和分子量的减小也发生变化。我们还证实THz光谱技术在监测膜蛋白的热变性时既有它的优越性，也存在一些不足之处。这些结果为THz-TDS技术在生物样品上的应用提供了基本的资料，并完善了相关的理论。

The dynamics of hippocampal sensory gating during the development of morphine dependence and withdrawal in rats

The effects of morphine on hippocampal sensory gating (N40) during the development of morphine dependence and withdrawal were investigated in the double click auditory evoked potential (EP) suppression paradigm. Rats were made dependent upon morphine hydrochloride by a series of injections (every 12h) over 6 days, followed by withdrawal after stopping morphine administration. Hippocampal gating was examined during the development of dependence and withdrawal. Moreover, the DA antagonist haloperidol was used to assess the contribution of dopamine to hippocampal gating induced by morphine. Our results showed that the morphine-treated rats exhibited significantly disrupted hippocampal gating during the development of morphine dependence and this disrupted gating was partially reversed by haloperidol pretreatment. In contrast, there was significantly enhanced hippocampal gating at the fifth and sixth days of withdrawal. The dynamics of hippocampal gating during the development of morphine dependence and withdrawal suggests the interaction between the hippocampus and opioids. (c) 2005 Elsevier Ireland Ltd. All rights reserved.

Hydrodynamics in an expanded bed of large size ion-exchange resin, and natural product adsorption

Successful applications of expanded bed adsorption (EBA) technology have been widely reported in the literature for protein purification. Little has been reported on the recovery of natural products and active components of Chinese herbal preparations using EBA technology. In this study, the hydrodynamic behavior in an expanded bed of cation resin, 001 x 7 Styrene-DVB, was investigated. Ephedrine hydrochloride (EH) was used as a model natural product to test the dynamic binding capacity (DBC) in the expanded bed. EBA of EH directly from a feedstock containing powdered herbs has also been investigated. These particles are different from commercially available expanded bed adsorbents by virtue of their large size (20S to 1030 gm). When the adsorbent bed is expanded to approximately 1.3 to 1.5 times its settled bed height, the axial liquid-phase dispersion coefficient was found to be of the order 10(-5) m(2) s(-1), which falls into the range 1.0 x 10(-6) to 1.0 X 10(-5) m(2) s(-1) observed previously in protein purification. Because of the favorable column efficiency (low axial dispersion coefficient), the recovery yield and purification factor values of EH directly from a feedstock reached 86.5% and 18, respectively. The results suggest that EBA technology holds promise for the recovery of natural products and active components of Chinese herbal preparations.