脂质体电动色谱法评价阿魏酸与生物膜的相互作用

利用脂质体与生物膜结构的相似性,将脂质体加入毛细管电泳缓冲溶液中作为假固定相,在数分钟内测定了阿魏酸的脂水分配系数Klw,建立了脂质体电动色谱评价阿魏酸与生物膜相互作用的方法。研究了脂质体中胆固醇的含量、缓冲溶液pH值和缓冲体系对Klw的影响。结果表明,在实验条件范围内(胆固醇含量0~30%,pH值4.0~12.0),胆固醇含量升高,缓冲溶液pH值增大,Klw降低;在不同的缓冲体系中,离子强度越大,Klw越大。脂水分配系数的变化反映了阿魏酸与生物膜相互作用。     

联用色谱及多组分光谱相关色谱用于当归补血汤与单味药成分的比较研究

摘要利用HPLC-DAD提供的二维化学数据信息, 通过多组分光谱相关色谱方法及化学计量学分辨技术, 对相同试验条件下所得的当归补血汤及其单味药的色谱组分进行了比较和归属分析. 结果表明， 在当归补血汤色谱响应值较高的21个色谱峰中, 8个色谱峰的组分来自当归, 6个色谱峰的组分来自黄芪, 7个色谱峰的组分同时来源于当归和黄芪. 其中一些色谱峰簇中的其它组分发生了消长变化， 既有新物质的产生, 又有原有化学成分的消失， 说明中药复方配伍的药效物质基础不仅是各单味药化学成分的总和, 还有单味药在复方配伍过程中各种成分的相互作用. 本方法为中药复方与单味药化学组分的比较及归属分析, 尤其对重叠色谱峰簇的组分比较分析提供了方便、 快捷及可行的研究方法.     

中药配伍的统一分析方法研究 Ⅱ.拟合定量

 配伍过程中物质组分的浓度变化需要进行定量 ,但复方中大量的重叠色谱峰影响定量的准确性。而在色谱理论基础上发展起来的拟合定量技术 ,可以对重叠色谱峰进行拟合定量。在统一分离和复方中单味药的特征物质组分得到识别的基础上 ,以黄芪、当归用量变化时 ,复方“当归补血汤”中黄芪、当归的特征物质组分的拟合定量为实例 ,介绍了中药配伍过程中定量的手段和研究方法     

卵磷脂涂敷生物膜色谱固定相的制备及其稳定性的考察

 将卵磷脂涂敷的硅胶作为生物膜固定相 ,并以此研究了药物与生物膜的相互作用。实验发现 ,卵磷脂涂敷的硅胶固定相的适宜使用温度为 2 0℃～ 30℃ ,而且卵磷脂中合适的胆固醇含量会使制备的生物膜固定相的稳定性有所增加。对药物在这种生物膜色谱固定相上的保留行为的研究表明 ,胆固醇含量、缓冲试剂组成、流动相中盐浓度及pH值等都会影响色谱柱对药物的选择性。卵磷脂涂敷生物膜色谱固定相的制备方法简便 ,通过固定相及流动相的改变可以很方便地模拟人体的生理环境 ,因而可以用于研究药物在体内的吸收和分布状况以及药物的初步筛选。     

聚丙烯酸对自然水体生物膜吸附镉的影响

选择聚丙烯酸(PAA)为水中溶解态高分子天然有机质的代表, 研究了PAA对自然水体生物膜吸附重金属Cd的影响, 包括不同浓度的PAA对吸附的影响, PAA对特定pH下吸附等温线的影响以及不同pH下按不同顺序添加PAA时对吸附的影响. 研究结果表明, PAA的存在一般会降低生物膜对Cd的吸附, 其影响程度与PAA的浓度、 溶液pH、 吸附顺序及生物膜厚度等有关. PAA与Cd的浓度比越高, 其对吸附的影响越显著. 吸附溶液pH越高, PAA的影响越显著. 吸附顺序对吸附的影响在pH较低时不明显, 当pH较高时, 先加PAA后加Cd及两者同时吸附时对吸附的降低作用接近且较大, 先加Cd后加PAA时对吸附的降低作用相对较小. 生物膜较薄时PAA的影响更显著. PAA对生物膜吸附Cd的影响主要由PAA与生物膜之间对Cd的竞争以及三元表面配合物的生成与吸附2种因素共同决定. 高pH会促进PAA与Cd的配合而不利于带负电的配合物在生物膜上的吸附.     

溶解有机质对光照自然水体生物膜体系中H2O2生成的影响

通过模拟实验研究了生物膜胞外聚合物(EPS)和乙二胺四乙酸(EDTA) 2种典型溶解有机质(DOM)成分对自然水体生物膜体系中过氧化氢(H₂O₂)生成特征的影响, 并研究了体系初始pH值、 DOM浓度、 溶解氧(DO)等因素的影响. 结果表明, DOM的存在对自然水体生物膜体系中H₂O₂的生成有明显影响. 光照能促使EPS产生H₂O₂, 而EPS的存在对生物膜产生H₂O₂的直接影响不显著, EPS与生物膜共存体系中的H₂O₂由二者共同产生; EDTA本身不产生H₂O₂, 且对H₂O₂分解影响很小, 但会显著抑制生物膜产生H₂O₂, 且浓度越高抑制作用越明显. 体系pH值、 DOM浓度和DO均能不同程度影响EPS产生H₂O₂及EDTA抑制生物膜产生H₂O₂的作用.     

不同水体生物膜中各化学组分对铅的吸附作用研究

水中的底泥、悬浮物和生物膜等固相物质对重金属在水中的迁移和转化有重要影响 [1,2 ] ,而固相物质中起主要作用的是吸附能力强的铁、锰氧化物和有机质 [3,4 ] .对生物膜与重金属相互作用的研究已经有报道 [5,6] .Nelson等[3] 用吸附加和模型模拟生物膜上各组分对铅吸附 ;Dong等 [7] 用选择性萃取的方法研究生物膜各组分对铅、镉的吸附情况 ,但他们的研究均局限于单一水体 ,本文采用萃取 -吸附-统计分析的方法研究多个自然水体生物膜中铁、锰氧化物和有机质对铅吸附的相对贡献 .1　实验部分1 .1　生物膜的培养及组分测定　选吉林省境内的净…     

固定化脂质体色谱研究中药复方的细胞膜通透性成分及其质量控制

提出了固定化脂质体色谱(immobilized liposome chromatography,ILC)研究中药复方的细胞膜通透性成分及其质量控制的方法。以当归补血汤及其组分为例,考察了它们在ILC色谱柱上的分离效果;当归补血汤水提取液和75％乙醇提取液在ILC色谱柱上各有8个保留峰,当归水提取液、甲醇提取液和75％乙醇提取液在ILC色谱柱上分别有3、6、9个保留峰,黄芪水提取液、甲醇提取液和75％乙醇提取液在ILC色谱柱上各有7个保留峰;建立了当归补血汤及其组分中阿魏酸和蒿本内酯的定量分析方法,当归补血汤水提取液和75％乙醇提取液中阿魏酸的含量分别为0．0743％和0．0688％,蒿本内酯的含量分别为0．0472％和0．457％,当归水提取液和75％乙醇提取液中阿魏酸的含量分别为0．0694％和0．0691％,蒿本内酯的含量分别为0．0781％和0．455％。     

低电渗流的毛细管区带电泳分离丹酰氨基酸

建立了低电渗流的毛细管区带电泳分离丹酰氨基酸的新方法,详细研究了缓冲体系的浓度,pH值以及各种添加剂的影响。发现组分迁移时间对缓冲体系pH值极为敏感;添加一定量的甘氨酸,使分离选择性极大的改善;即,能改善待测组分的电离平衡的因素均能有效地改善分离选择性,对低电渗流区带电泳分离机制进行了详尽的讨论。     

脱氧胆酸钠与支撑磷脂双层膜作用的电化学研究

以支撑磷脂双层膜(supported bilayer lipid membrane, s-BLM)作为生物膜模型, 采用循环伏安法和交流阻抗技术研究了脱氧胆酸钠(sodium deoxycholate, NaDC)与s-BLM的相互作用. 结果表明, NaDC能降低磷脂分子的有序性, 诱发s-BLM上形成孔洞或缺陷, 并且它们之间的这种相互作用对作用时间、NaDC溶液的浓度和pH值以及胆固醇的存在与否具有依赖性, 并且作用后的s-BLM在0.1 mol/L的KCl溶液中能够自我修复, 这表明NaDC与s-BLM的相互作用是可逆的.     

Preliminary Screening and Analysis of Biomembrane Permeable Compounds in Herbal Medicines: Hollow Fiber Liposome Microscreening Combined with HPLC

An advantageous method based on hollow fiber liposome microscreening (HFLMS) combined with high-performance liquid chromatography (HPLC) has been developed and used in preliminary screening and analysis of biomembrane permeable compounds from herbal medicines (HMs). In the method, a liposome hollow fiber was prepared as a screening tool; permeable compounds that could specifically bind to liposomes were screened from herbal extract to liposome in the pores and lumen of hollow fiber, then permeable compounds were dissociated from liposomes and analyzed by HPLC. The chromatographic separation was applied with a Zorbax Eclipse XDB-C18 column by a gradient elution using acetonitrile, methanol, and phosphoric acid aqueous solution as the mobile phases. In the study, influencing factors of the screened target compounds were investigated and optimized. Under optimum conditions, the surface properties of liposome hollow fibers were characterized, the nonspecific binding between the active center of hollow fiber and the bioactive components were investigated, the repeatability of this method was tested. And eight permeable compounds of flavonoids and anthraquinones from HMs were preliminarily screened and analyzed by HFLMS-HPLC. The results demonstrated that new method is a simple, fast, effective, and reliable method for preliminary screening and analyzing biomembrane permeable ingredients in HMs, and it can be used in screening other permeable compounds in HMs.

     

Preliminary Screening and Analysis of Biomembrane Permeable Compounds in Herbal Medicines: Hollow Fiber Liposome Microscreening Combined with HPLC

An advantageous method based on hollow fiber liposome microscreening (HFLMS) combined with high-performance liquid chromatography (HPLC) has been developed and used in preliminary screening and analysis of biomembrane permeable compounds from herbal medicines (HMs). In the method, a liposome hollow fiber was prepared as a screening tool; permeable compounds that could specifically bind to liposomes were screened from herbal extract to liposome in the pores and lumen of hollow fiber, then permeable compounds were dissociated from liposomes and analyzed by HPLC. The chromatographic separation was applied with a Zorbax Eclipse XDB-C18 column by a gradient elution using acetonitrile, methanol, and phosphoric acid aqueous solution as the mobile phases. In the study, influencing factors of the screened target compounds were investigated and optimized. Under optimum conditions, the surface properties of liposome hollow fibers were characterized, the nonspecific binding between the active center of hollow fiber and the bioactive components were investigated, the repeatability of this method was tested. And eight permeable compounds of flavonoids and anthraquinones from HMs were preliminarily screened and analyzed by HFLMS-HPLC. The results demonstrated that new method is a simple, fast, effective, and reliable method for preliminary screening and analyzing biomembrane permeable ingredients in HMs, and it can be used in screening other permeable compounds in HMs.     

One single standard substance for the determination of multiple anthraquinone derivatives in rhubarb using high-performance liquid chromatography-diode array detection

Due to the complexity of the chemical constitution of traditional Chinese medicines (TCMs), now there is a trend to establish methods, using multi-components analysis, for the effective quality control of TCMs. However, the limited availability of multiple reference substances hinders the wide popularization for routine quality control of TCMs. Using an easily available single component contained in the analyte as an internal standard to determine multiple analogues should be a practical option. In this study, we selected rhubarb rhizome as an example, and used emodin, the easily available active component, as the external standard to determine directly the content of emodin in rhubarb, and the same component as the internal standard to simultaneously determine the other six anthraquinones in rhubarb. Compared with the results obtained using the external standard method, this alternative method was found to have no statistically significant differences in our laboratory as verified by the F-test (p = 95%, n = 6). However, due to weak robustness caused by the fluctuation of relative response factors in different laboratories, such a method can only serve as a practical measure to solve the lack of so many chemical standard substances when relative response factors have been determined. This alternative method can then be used without reference substances. Once the corresponding chemical standards are available and are acceptable as well as cost-effective, then the external standard method for the simultaneous determination of multiple components (SDMC) in TCMs will prevail.     

A Study of Two-Dimensional Microdischarge Pattern Formation in Dielectric Barrier Discharges

Although microdischarges in dielectric-barrier discharges (DBDs) have been studied for the past century, their mutual interaction was explained only recently. This interaction is responsible for the formation of microdischarge patterns reminiscent of two-dimensional crystals. Depending on the application, microdischarge patterns may have a significant influence on DBD performance, particularly when spatial uniformity is desired. This paper presents the results of study of regular microdischarge pattern formation in DBD in air at atmospheric pressure. Experimental images of DBD (Lichtenberg figures) were obtained using photostimulable phosphors. A new method for analysis of microdischarge patterns that allow measuring the degree of pattern regularity was developed. Simulated and experimental patterns were compared using the newly developed method and comparison indicates the presence of interaction between microdischarges. Analysis of microdischarge patterns shows that regularity of the patterns increases with the number of excitation cycles used to produce the pattern.     

模拟生物膜色谱用于预测药物的小肠吸收

采用涂敷磷脂的硅胶为模拟生物膜色谱固定相,与传统的凝胶体相比固定相的机械强度及磷脂固载能力均有较大提高,且有较好的稳定性。研究发现氢化可的松等6种药物在模拟生物膜色谱上pH5.4、pH7.0及pH7.4三种缓冲环境下的色谱保留值迭加的结果能够与药物的肠吸收指数押送好的拟合,线性相关系数为0.9365,该结果高于单一pH条件下拟合结果,并将此结果与药物在C18反相色谱上的保留值及辛醇-水系统下的分配系数与药物的小肠吸收的拟合结果进行比较,表明与这两种模型相比模拟生物膜色谱预测药物的小肠吸收有更高的准确度。     

Separation methods for toxic components in Traditional Chinese Medicines.

Traditional Chinese medicines (TCMs) with many unique functions for treating diseases have attracted the interest of people worldwide. They have been popularly utilized for therapy and health promotion in most Asian countries and even in many European and North American countries. However, it should be clearly noted that TCMs are mixtures with complicated composition usually containing hundreds, even thousands of chemically different constituents, and it is the multiple constituents that work synthetically to determine the ultimate effect of a formula of TCM. Meanwhile, some components with toxicity in some TCMs, having various negative effects on different parts of body, may do serious harm to people's health; such harm in particular requires our attention. In this article, applications of different chromatographic and electrophoretic techniques in the analysis of toxic components in TCMs in recent decades have been comprehensively reviewed and some hyphenated procedures (combinations of two kinds of measurement) applied in this field are also summarized.     

Influence of Plasma Treatments on the Hemocompatibility of PET and PET + TiO<Subscript>2</Subscript> Films

A dielectric barrier discharge (DBD) in helium was used to ameliorate the interface between the blood and the surface of polymeric implants: polyethylene terephthalate (PET) and PET with titanium oxide (PET + TiO₂). A higher crystallinity degree was found for the DBD treated samples. The wettability of polymers was improved after the treatment. The chemical composition, analyzed by infrared spectroscopy was preserved during the DBD treatment. The surface modifications have been correlated with polymers hemocompatibility. Concerning the polymer surface–blood interaction, the treatment induced a decrease of the interfacial tension between the blood components and the treated surfaces. The in vitro tests of hemocompatibility showed no perturbation in the blood composition when the polymer samples are present in the blood volume. An interesting result is related to the whole blood clotting time that shows a dramatic increase on the treated surfaces. Moreover, the coagulation kinetics on the treated surfaces is modified.     

Binding study of Flos Lonicerae Japonicae with bovine serum albumin using centrifugal ultrafiltration and liquid chromatography

The screening and analysis of bioactive components in traditional Chinese medicines (TCMs) is very important not only for the quality control of Chinese herbs but also for elucidating the therapeutic principles. This study developed a new method for screening and analyzing bioactive compounds from TCMs using centrifugal ultrafiltration coupled with high-performance liquid chromatography. The method was successfully applied in the binding study of Flos Lonicerae Japonicae with bovine serum albumin (BSA), and 11 compounds were found to be bound with the BSA. Eight of them were positively identified as chlorogenic acid, caffeic acid, rutin, quercetin-3-O-glucoside, luteolin-7-O-glucoside, lonicerin, 3, 5-di-O-caffeoyl quinic acid and 3,4-di-O-caffeoyl quinic acid. Another three compounds were tentatively identified as two isomers of chlorogenic acid and one isomer of di-O-caffeoyl quinic acid by comparing the UV data and MS data with the previous reports. Based on modern pharmacological study, these compounds are the major bioactive components in Lonicera japonica. Therefore, the proposed method could be a good approach to predicting the potential bioactivities of multiple compounds in TCMs simultaneously.     

介质阻挡放电等离子体与吸附在CuZSM-5上的NO或NO/O2的相互作用

采用吸附和程序升温脱附(TPD)技术研究了介质阻挡放电等离子体对CuZSM-5催化剂上吸附的氮氧化物作用. 实验表明, 介质阻挡放电等离子体使催化剂表面吸附的NO及Cu活性位上吸附的NOx物种脱附, 并引发表面化学反应生成新的氮氧化物. 对于NO/N2体系, 介质阻挡放电等离子体与吸附在CuZSM-5上NO作用, 主要生成N2O和O2. 在富氧体系NO/O2/N2, 则生成较大量的N2O、NO2和NO. 等离子体预处理活性下降的CuZSM-5, 可明显提高其催化分解NO活性. 对比有或无介质阻挡放电等离子体预处理NO或NO/O2饱和吸附的CuZSM-5上的NO-TPD结果表明, 等离子体提高催化剂活性的原因与其使催化剂Cu活性位上吸附的NOx物种脱附有关.