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1.
利用相溶解度曲线研究不同浓度的羟丙基-β-环糊精(HP-β-CD)与布洛芬(BF)的超分子相互作用。采用高效液相色谱法(HPLC)建立布洛芬的标准工作曲线。配制系列浓度的HP-β-CD溶液,加入过量的布洛芬,采用HPLC法测定布洛芬的溶解度,绘制相溶解度图。结果显示,HP-β-CD与布洛芬的相溶解度曲线为线性关系,说明两者之间包合模型为AL型,布洛芬与HP-β-CD以1∶1包合,其包合常数K为7.23×10~3 L/mol。羟丙基-β-环糊精对布洛芬形成的超分子化合物均有较好的增溶作用。  相似文献   

2.
利用相溶解度曲线研究不同浓度的羟丙基-β-环糊精(HP-β-CD)与布洛芬(BF)的超分子相互作用。采用高效液相色谱法(HPLC)建立布洛芬的标准工作曲线。配制系列浓度的HP-β-CD溶液,加入过量的布洛芬,采用HPLC法测定布洛芬的溶解度,绘制相溶解度图。结果显示,HP-β-CD与布洛芬的相溶解度曲线为线性关系,说明两者之间包合模型为AL型,布洛芬与HP-β-CD以1∶1包合,其包合常数K为7.23×103 L/mol。羟丙基-β-环糊精对布洛芬形成的超分子化合物均有较好的增溶作用。  相似文献   

3.
以羟丙基-β-环糊精(HP-β-CD)为手性流动相添加剂,研究了氟比洛芬对映体在反相高效液相色谱中的拆分。考察了羟丙基-β-环糊精的浓度、流动相pH值、有机调节剂、柱温对手性分离的影响,同时探讨了HP-β-CD对氟比洛芬对映体在反相高效液相中的分离机制且计算出相应的包结常数。确定了色谱条件:YMC-Pack ODS-A C18(150 mm×4.6 mm,5μm)色谱柱,流动相为0.5%乙酸(pH3.5,三乙胺调节)含25 mmol/L羟丙基-β-环糊精:甲醇(80:20,v/v),流速为1.0 mL/min,柱温为30℃,紫外检测波长为247 nm。通过容量因子(k’)的倒数1/k’对[HP-β-CD]的良好的线性关系证明氟比洛芬与HP-β-CD形成包结比为1:1包结物,(+)-氟比洛芬的包结常数为1.83 L/mol,(-)-氟比洛芬的包结常数为1.67 L/mol。  相似文献   

4.
通过溶液共混法制备青藤碱-羟丙基-β-环糊精包合物,纯化后利用体视显微镜观察包合物的结晶形态,通过差热示重扫描、红外光谱、X射线粉末衍射及核磁共振等方式对包合物进行性质分析,并通过相溶解度法计算包合物的包合常数。结果表明青藤碱-羟丙基-β-环糊精包合物性质发生明显变化,羟丙基-β-环糊精能显著增加青藤碱的溶解度,青藤碱-羟丙基-β-环糊精包合物是一种稳定的新物质,青藤碱与HP-β-CD形成的包合物的包合分子比为1∶1,其包合常数为150.0。  相似文献   

5.
以β-环糊精(β-CD)和功能单体4-乙烯基吡啶(4-VP)制备了基于阿司匹林的超分子印迹聚合物β-CD/4-VP-MIP,通过红外光谱(FT-IR)、扫描电镜(SEM)和N2吸附-脱附仪,对所合成β-CD/4-VP-MIP的组成、形貌和比表面积进行了表征,并考察了其对阿司匹林的吸附选择性、等温吸附线及动力学。结果表明:所合成的β-CD/4-VP-MIP具有较大的比表面积和丰富的孔道结构;对阿司匹林的等温吸附过程遵从Langmuir方程,饱和吸附量为42.918 mg/g;吸附动力学遵从准二级动力学方程,吸附速率为0.002 8 g/(mg·min);热力学分析表明,该吸附过程为吸热、自发、熵增过程。  相似文献   

6.
采用包合法制备呋塞米与羟丙基-β-环糊精(HP-β-CD)包合物并对其包合常数等进行测定。配制HP-β-CD溶液,加入过量呋塞米制备包合物,使用红外光谱法和薄层色谱法对包合物进行鉴定,通过相溶解度法对HP-β-CD与呋塞米的相互作用进行考察。结果表明,相溶解度曲线为线性关系,表明两者之间为AL型包合,包合比例1∶1。包合常数随温度升高而增大。37℃、HP-β-CD浓度为0.486 5 mol/L时,呋塞米的增溶倍数可高达32.10倍。采用HP-β-CD包合法,可显著改善呋塞米的溶解性,为呋塞米新剂型的开发提供依据。  相似文献   

7.
采用包合法制备呋塞米与羟丙基-β-环糊精(HP-β-CD)包合物并对其包合常数等进行测定。配制HP-β-CD溶液,加入过量呋塞米制备包合物,使用红外光谱法和薄层色谱法对包合物进行鉴定,通过相溶解度法对HP-β-CD与呋塞米的相互作用进行考察。结果表明,相溶解度曲线为线性关系,表明两者之间为AL型包合,包合比例1∶1。包合常数随温度升高而增大。37℃、HP-β-CD浓度为0.486 5 mol/L时,呋塞米的增溶倍数可高达32.10倍。采用HP-β-CD包合法,可显著改善呋塞米的溶解性,为呋塞米新剂型的开发提供依据。  相似文献   

8.
为了提高β-(3,5-二叔丁基-4-羟基苯基)丙酰肼(3,5-丙酰肼)的水溶性,采用饱和水溶液法制备了3,5-丙酰肼-羟丙基-β-环糊精包合物(包合物),并通过TLC、IR和DSC等分析手段对包合物进行鉴定。利用紫外分光光度法考察了羟丙基-β-环糊精(HP-β-CD)和3,5-丙酰肼的投料摩尔比对包合效果的影响及HP-β-CD对3,5-丙酰肼的增溶作用。结果表明,随HP-β-CD与3,5-丙酰肼投料摩尔比的增大,所得包合物中3,5-丙酰肼的含量减小,包合物产率和3,5-丙酰肼的包合率均有所增大。当HP-β-CD与3,5-丙酰肼的投料摩尔比为3∶1时,包合物产率和3,5-丙酰肼的包合率均为100%,达到最优包合效果。经HP-β-CD包合后,3,5-丙酰肼的水溶性得到显著提高,由不溶于水变为可溶于水。当HP-β-CD与3,5-丙酰肼投料摩尔比为1∶1时,包合物的溶解度最高,可达9.0 g/100 g水。  相似文献   

9.
目的制备PLGA聚合物-羟丙基-β-环糊精-丹参酮IIA纳米体系,以改善丹参酮IIA的溶解性,为其靶向缓释给药奠定实验基础。方法采用单因素法考察丹参酮IIA-羟丙基-β-环糊精包合物制备最优处方;采用复乳化溶剂挥发法制备PLGA聚合物-羟丙基-β-环糊精-丹参酮IIA纳米体系,并考察其包封率、粒径、PDI及ZETA电位。结果丹参酮IIA制备成羟丙基-β-环糊精包合物后,水溶性显著提高;以包合物作为内水相制得PLGA聚合物-羟丙基-β-环糊精-丹参酮IIA纳米体系,纳米粒包封率高,粒径分布均匀。结论 PLGA聚合物-羟丙基-β-环糊精-丹参酮IIA纳米体系有望成为丹参酮IIA新型制剂。  相似文献   

10.
考察了β环糊精(β-CD)、羟丙基-β-环糊精(HP-β-CD)、羧甲基-β-环糊精(CM-β-CD)在有重金属离子Cd^2 存在下对α-淀粉酶活性的保护作用。结果表明,三种环糊精化合物对酶的活性有不同程度的保护作用,其中CM-β-CD的效果最好。  相似文献   

11.
《分离科学与技术》2012,47(15):2342-2351
Molecular imprinted polymer (MIP MAA-β-CD) with 2,4-dichlorophenol (2,4-DCP) and methacrylic acid functionalized β-cyclodextrin (MAA-β-CD) as the template molecule and the functional monomer, respectively, was prepared and used in molecular imprinted-solid phase extraction (MISPE) for the extraction of phenols (2,4-dichlorophenol, 2-chlorophenol, 4-chloro-3-methylphenol, 4-chlorophenol, 2,4,6-trichlorophenol, and 2-nitrophenol) from water samples. The MISPE method was optimized prior to the determination using gas chromatography coupled with a flame ionization detector (GC-FID). Under the optimized conditions, the MIP MAA-β-CD sorbent showed good linearity (0.01-12 mgL?1), low limits of detection (0.14-0.75 µgL?1), and good repeatability (RSD 2.3-3.6%, n = 3). Good recoveries were obtained in the range of 97-115% for tap water and between 88-103% for river water. The developed MIP MAA-β-CD SPE was then compared with other adsorbents. The unique properties of β-CD and presence of imprinted cavities explains the higher extraction recoveries obtained for phenols when using MIP MAA-β-CD SPE.  相似文献   

12.
利用分子印迹技术的特异性识别,采用本体热聚合,以酸碱相互作用为基本作用机理,分别以甲基丙烯酸二甲氨基乙酯(DMAEMA)、甲基丙烯酸二乙氨基乙酯(DEAM)、甲基丙烯酸-2-氨基乙基酯盐酸盐(AMA盐酸盐)、4-乙烯基吡啶(4-VP)和甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)和二乙烯基苯(DVB)为交联剂,偶氮二异丁腈(AIBN)为引发剂,乙腈为溶剂设计合成了三氯生(TCS)的分子印迹聚合物(MIPs)。吸附结果表明,其中DEAM是TCS的最佳功能单体,吸附率达到了78.5%,印迹因子达到了1.7,用DEAM作为功能单体合成的MIPs对TCS的选择性实验结果显示,对TCS的吸附容量明显高于其结构类似物,对TCS的吸附实验结果显示,5次回收后重复利用,吸附容量仅降低了5.1%,表明该MIPs可以重复使用多次。  相似文献   

13.
采用相溶解度法探讨羟丙基-β-环糊精(HP-β-CD)对依达拉奉的增溶作用。在水溶液中,依达拉奉的浓度随HP-β-CD浓度的增加而呈线性增加,相溶解度曲线为AL型。经HP-β-CD包合后依达拉奉在水中的溶解度最高可达包合前的5.026倍,包合物的稳定常数Kc=10.31。  相似文献   

14.
The molecularly imprinted polymer (MIP) based on methacrylic acid functionalized β-cyclodextrin (MAA-β-CD) monomer was synthesized for the purpose of selective recognition of benzylparaben (BzP). The MAA-β-CD monomer was produced by bridging a methacrylic acid (MAA) and β-cyclodextrin (β-CD) using toluene-2,4-diisocyanate (TDI) by reacting the –OH group of MAA and one of the primary –OH groups of β-CD. This monomer comprised of triple interactions that included an inclusion complex, π–π interaction, and hydrogen bonding. To demonstrate β-CD performance in MIPs, two MIPs were prepared; molecularly imprinted polymer-methacrylic acid functionalized β-cyclodextrin, MIP(MAA-β-CD), and molecularly imprinted polymer-methacrylic acid, MIP(MAA); both prepared by a reversible addition fragmentation chain transfer polymerization (RAFT) in the bulk polymerization process. Both MIPs were characterized using the Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), and Brunauer-Emmett-Teller (BET). The presence of β-CD not only influenced the morphological structure, it also affected the specific surface area, average pore diameter, and total pore volume of the MIP. The rebinding of the imprinting effect was evaluated in binding experiments, which proved that the β-CD contributed significantly to the enhancement of the recognition affinity and selective adsorption of the MIP.  相似文献   

15.
2-methylphenoxyacetic acid (2-MPA), 2-methyl-4-chlorophenxyacetic acid (MCPA) and 4-chlorophenoxyacetic acid (4-CPA) were imprinted to investigate the cross-selectivities of molecularly imprinted polymers (MIPs). The result indicates that 2-MPA, which is similar in shape, size and functionality with phenoxyacetic herbicides, are suitable to be used as a suitable template to prepare the MIPs for retaining phenoxyacetic herbicides. To study the ion-pair interactions between template molecules and functional monomer 4-vinylpiridine (4-VP), computational molecular modeling was employed. The data indicate that the cross-selectivities of MIPs for phenoxyacetic acid herbicides depend on the binding energies of complexes.  相似文献   

16.
Fmoc-3-nitrotyrosine (Fmoc-3-NT) molecularly imprinted polymers (MIPs) were synthesized to understand the influence of several functional monomers on the efficiency of the molecular imprinting process. Acidic, neutral and basic functional monomers, such as acrylic acid (AA), methacrylic acid (MAA), methacrylamide (MAM), 2-vinylpyridine (2-VP), 4-vinylpyridine (4-VP), have been used to synthesize five different polymers. In this study, the MIPs were tested in batch experiments by UV-visible spectroscopy in order to evaluate their binding properties. The MIP prepared with 2-VP exhibited the highest binding affinity for Fmoc-3NT, for which Scatchard analysis the highest association constant (2.49 × 10(4) M(-1)) was obtained. Furthermore, titration experiments of Fmoc-3NT into acetonitrile solutions of 2-VP revealed a stronger bond to the template, such that a total interaction is observed. Non-imprinted polymers as control were prepared and showed no binding affinities for Fmoc-3NT. The results are indicative of the importance of ionic bonds formed between the -OH residues of the template molecule and the pyridinyl groups of the polymer matrix. In conclusion, 2-VP assists to create a cavity which allows better access to the analytes.  相似文献   

17.
环糊精对黄酮的包合作用及其在银杏黄酮提取中的应用   总被引:5,自引:0,他引:5  
对β-环糊精(-βCD)进行甲基化修饰和表征,并通过相溶解度法研究了β-CD以及甲基化β-环糊精(M-β-CD)对银杏黄酮的替代品———芦丁的包合作用。实验表明,两种环糊精都能有效增加芦丁在水中的溶解度,尤其是M--βCD可使溶解度增加30倍。以此为依据,该研究用含有β-CD和M-β-CD的水溶液来提取银杏叶中的黄酮,探讨了环糊精与黄酮的摩尔比、提取温度和提取时间对提取效果的影响,结果发现:当n(M--βCD)∶n(黄酮)=3∶1,60℃下提取3 h后,黄酮的提取率达72%,w(黄酮)=12.4%,较传统的水浸法〔提取率42%,w(黄酮)=4.5%〕和醇提法〔提取率63%,w(黄酮)=6.1%〕有明显的提高。这表明通过-βCD及M--βCD对银杏黄酮的溶解和包合作用,可有效地提高黄酮的提取率以及提取物纯度。  相似文献   

18.
Guest-host complex formation of three drug derivatives of anthranilic acid, mefenamic acid, niflumic acid, and flufenamic acid with 2-hydroxypropyl-β-cyclodextrin (2HP-β-CD) in aqueous solutions was investigated using "Phase solubility study" with UV-vis spectrophotometry. Solubility of sparingly soluble drugs has been improved by addition of 2HP-β-CD at two temperatures 298.15 K and 310.15 K and two pH values 2 and 7. The influence of different 2HP-β-CD concentration on solubility of drugs at different pH and temperatures has been investigated. The 2HP-β-CD-drug complex stability constants (K(s)), and dissociations constants (K(d)), as well as the thermodynamic parameters of reaction, i.e., the free energy change (ΔG), the enthalpy change (ΔH) and the entropy change (ΔS), were determined. The experimental data indicated formation of 1:1 inclusion complexes, which were found effective binders increasing the solubility of drugs.  相似文献   

19.
Owing to the high specific surface area and lightweight, aerogels exhibit excellent adsorption capacity that can be tailored for the fabrication of high-performance environmental purification materials. Cellulose nanocrystal (CNC) is an abundant, bio-based, low-density one dimensional (1D) nanomaterials with high-respect ratio. In this work, CNC is first chemically grafted with polyethylenimine (PEI) and further by β-cyclodextrin (β-CD), which is subsequently crosslinked by polyacrylamide (PAM) to prepare the composted aerogel (CNC-PEI-CD/PAM), and being endowed high-adsorption capacity for methyl orange (MO) (155.93 mg g−1) and removal rate (97.46%). Our unique strategy overcomes the low graft efficiency of β-CD directly onto CNC by connecting PEI. Besides, CNC-PEI-CD/PAM not only shows superior adsorption performance to methyl orange, attributing to the unique “selective” cavity structure of β-CD and dense surface charge of PEI, but also displays the desired reusability. This material shows the huge potential in water purification.  相似文献   

20.
朱士龙  陈迪钊  李勇  林红卫  段友构 《精细化工》2012,29(2):159-163,208
通过溶液共混法制备青藤碱-羟丙基-β-环糊精包合物,纯化后利用体视显微镜观察包合物的结晶形态,通过差热示重扫描、红外光谱、X射线粉末衍射及核磁共振波谱等方法对包合物进行性质分析,并通过相溶解度法计算包合物的包合常数。结果表明,青藤碱、羟丙基-β-环糊精包合后性质发生明显变化,羟丙基-β-环糊精能显著增加青藤碱的溶解度,包合物中青藤碱与羟丙基-β-环糊精包合分子个数比为1∶1,其包合常数为150.0 L/mol,反应的吉布斯自由能为-12.41 kJ/mol。  相似文献   

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