微透析探针的制备及其在Ni(Ⅱ)与人血清白蛋白的相互作用研究中的应用

介绍了一种自制微透析探针的制备方法,考察了灌流液流速、温度以及探针膜面积等因素对金属离子Ni(Ⅱ) 回收率的影响。实验结果表明:自制微透析探针透析金属离子的各种指标都与商品的微透析探针性能相当,可以替代商品化微透析探针研究金属离子与蛋白质的相互作用。利用微透析与高效液相色谱联用技术研究了Ni(Ⅱ)与人血清白蛋白(HSA)的相互作用。用自制的微透析探针测定Ni(Ⅱ)与HSA之间的第一结合位点数和结合常数分别为1.16和8.6×105 L/mol,采用商品的微透析探针测定的结果分别为1.23和7.5×105     

微透析——高效液相色谱法测定病人血清中肌酐含量

以微透析作为样品预处理技术，与高效液相色谱分析相结合建立了一个测定血清样品中肌酐浓度的方法。同时考察了温度、灌注流速对对微透析取样回收率的影响。微透析取样在３７℃、灌注流速为２．０μＬ／ｍｉｎ时回收率２２．２９％，ＲＳＤ８．２７％，利用这种方法病人血清中肌酐浓度，简单、快速、重复性较好。     

微透析与高效液相色谱在线联用技术校正大鼠皮下阿魏酸线性探针

采用微透析与高效液相在线联用技术(MD-HPLC on-line)建立并验证大鼠皮下阿魏酸微透析线性探针体内外校正方法.以磷酸盐缓冲溶液为灌流液,微透析灌注液流速为2 μ L/min,10孔自动进样阀间隔为8 min,在以Hypersil-C18(250 mm×4.6 mm,5μm)为色谱柱,流动相为甲醇-水(含0.5％乙酸)(35∶ 65,V/V),流速1 mL/min,检测波长314 nm的HPLC色谱条件下进行在线检测,阿魏酸在0.1～80 mg/L范围内回归方程线性关系良好,A=159044C-2607 (r=1),阿魏酸日内精密度RSD分别为0.8％,0.3％和0.5％(n=5);日间精密度RSD分别为0.2％,0.3％和0.4％(n=5),重现性与稳定性RSD分别为0.7％和1.1％(n=5).增量法和减量法测定阿魏酸线性探针体内外回收率分别为47.23％±0.94％和20.37％±1.37％,阿魏酸适宜进行微透析实验.应用MD-HPLC on-line对中药当归阿魏酸进行测定,使取样、进样和分析监测同时进行.     

微透析联用反相高效液相色谱对大鼠皮肤葛根素的药代动力学研究

采用在体微透析取样技术联用RP-HPLC的方法对大鼠皮肤中的葛根素进行了体内药代动力学的考察.将微透析探针进行体内外校正后,植入大鼠皮下,以磷酸盐缓冲溶液作为灌流液,收集的样品在以Hypersil-C18(150 mm×4.6 mm, 5 μm)为色谱柱,流动相为V(甲醇)∶ V(0.1% 醋酸)＝30∶ 70,流速1 mL/min,检测波长221 nm的HPLC色谱条件下进行分析,所得的大鼠皮下游离葛根素浓度用Kinetica软件进行处理.结果显示:微透析探针体内外校正结果显示葛根素适宜应用微透析技术,在所建立的HPLC条件下葛根素在0.1～100 mg/L范围内线性关系良好(r=0.9999, n=6),浓度为100、10和0.1 mg/L的葛根素日内RSD分别为0.38%、0.80%和1.21%(n=6);日间RSD分别为0.44%、0.73%和1.68%(n=6),所得数据经Kinetica软件拟合后,得到大鼠皮下非结合葛根素药-时曲线和主要药动学参数.所建立的微透析联用RP-HPLC方法能够在体、实时监测大鼠皮下葛根素浓度.     

藻酸铜人造半透膜的制备

半透膜是一种专用于渗透实验的材料,工业上也可用来分离电解质。天然的半透膜广泛地存在于动植物体内,惜其形态大多不便于应用。最初习用之天然半透膜有动物(猪、牛)膀胱,人造半透膜则有羊皮纸等。作者在研究藻酸铵的制造中,作了一些藻酸化学性质的实验;并做成一种半透膜。现将制法简单介绍于下: 1.溶液的制备 (1)藻酸盐胶液——取藻酸铵(或其他可溶性藻酸盐)5克置烧杯中,加水100毫升,溶解完圣均匀后,即可应用。此液不宜储存太久,当发现胶液中的粘滞性消失或太差时,应另行     

杨树嫩茎质外体微透析液中K+,Na+,Ca2+的分析

采用微透析法获取3种杨树嫩茎质外体汁液的灌流液,流速1μL/min,探针截留分子量为30 kDa,无须处理直接通过原子吸收光谱(石墨炉法)测定样品中Na+,K+,Ca2+浓度,通过建立实时、无损检测离子浓度变化的实验技术,进行杨树生理生化的研究。此方法加标回收率在95.8%~103.1%之间。研究表明,吴屯杨、小胡杨和小美旱的Na+含量分别为1034~1156μg/L,1493~1611μg/L和1586~1703μg/L;K+含量分别为1012~1237μg/L,941~964μg/L和1095~1201μg/L;Ca2+含量分别为4976~5237μg/L,4786~5042μg/L和5893~6142μg/L,本方法为在植物应激反应中通过离子浓度变化来适应外界环境的研究提供可靠数据。     

脊髓损伤模型中胞外抗坏血酸浓度的活体在线分析

利用活体微透析技术结合在线高选择性抗坏血酸电化学检测技术,以实验性胸10节段脊髓钳夹损伤为动物模型,研究了脊髓损伤过程中胞外抗坏血酸的变化规律.结果表明,微透析探针植入及钳夹损伤瞬间,均存在脊髓抗坏血酸浓度高峰,随后浓度回到稳定水平,对照组大鼠脊髓细胞外液中抗坏血酸的平均基础浓度为(26.17±1.25)μmol/L(n=8).实验组脊髓钳夹损伤后,胞外抗坏血酸水平显著增加,达到(53.24±1.95)μmol/L(n=8),这种显著性升高可能与继发性脊髓损伤保护机制导致胞内抗坏血酸外流相关.本研究结果为抗坏血酸参与调节继发性脊髓损伤提供了直接的实验证据.     

离子交换树脂膜及其应用 Ⅰ.离子交换树脂膜

通常所谓膜就是指薄而柔软可折叠的一切天然物和人工制造的东西。根据它们在溶液里的性质可分为不透膜和半透膜二类。不透膜对于一切离子和分子都完全不能透过,这类性质的膜是很少存在。半透膜对于某些离子和分子可以透过而对于其他离子和分子完全不能或极少能透过,绝大部分的膜都是属于这类的,例如纤维素膜、羊皮纸、玻璃膜、硝化棉膜和许多动植物体内的器官表皮和细胞膜等,由于生理现象和这些膜的半透作用有密切关系,因此很早以前就对这些膜的半透性加以研究,并且应用到工业上和实验室里,例如电解净水,隔膜电解合成无机化合物等。     

乳及乳制品中黄曲霉毒素B_1、M_1测定方法改进

建立了一种检测乳及乳制品中黄曲霉毒素B1、M1的高效液相色谱-荧光检测(HPLC-FD)方法。样品经60%乙腈溶液提取,自制固相萃取柱净化,流出液经正己烷、三氟乙酸衍生后荧光检测器检测。考察了填料、柱容量、取样量、提取溶液和流速等对检测的影响,优化了实验条件。结果表明,黄曲霉毒素B1、M1的检测线性范围为0.40~100μg/L,线性系数为0.9991~0.9998,方法检出限为0.050μg/kg。对样品进行0.40、1.0和15μg/L 3种浓度水平的加标回收实验,回收率为53%~105%,相对标准偏差为2.6%~5.1%。该方法操作简单、灵敏度高、准确度好,可用于乳及乳制品中黄曲霉毒素B1、M1的测定。     

正交法优化大孔树脂提纯罗布麻中总黄酮的工艺

采用正交试验法,优选大孔树脂提纯罗布麻中总黄酮的最佳工艺。以芦丁为对照品,采用分光光度法进行测定,以罗布麻中总黄酮回收率为考察指标,对影响总黄酮纯化工艺的因素进行研究;在单因素实验基础上,选择树脂种类、p H值、料液浓度、解吸液乙醇浓度等4个因素进行正交试验,研究不同因素交互作用及其对黄酮回收率的影响,结合吸附和解吸流速,确定罗布麻总黄酮提纯的最佳工艺;用高效液相色谱法对提纯前后芦丁含量进行比较,验证纯化效果。经正交试验,确定最佳工艺参数如下:AB-8树脂,料液浓度为0.125mg/mL,p H=5,吸附流速为3mL/min,解吸液乙醇浓度为80%,解吸流速为5mL/min。在此工艺条件下,总黄酮产率为2.64%,总黄酮含量由10.1mg/g提高到378.6mg/g;经高效液相色谱法计算,芦丁含量由6.3mg/g提高到185.6mg/g。     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.