共查询到20条相似文献,搜索用时 125 毫秒
1.
流动相组成、浓度和pH对蛋白质在金属螯合柱上的保留特性的影响 总被引:6,自引:0,他引:6
系统研究了流动相中盐的性质和浓度、溶液 pH以及竞争配体对蛋白质在金属螯合色谱中保留值的影响。导出了描述蛋白质在金属螯合色谱中保留特征的数学表达式 ,提出用洗脱强度指数ε表征盐溶液的洗脱能力。根据不同色谱条件下蛋白质的保留特性 ,发现蛋白质在金属螯合色谱中的保留是配位、静电和疏水的协同作用。对与蛋白质强结合的金属螯合柱 ,以配位作用为主 ,静电作用为辅 ;对弱结合的金属柱 ,以静电作用为主 ,配位作用为辅。在流动相中加入高浓度非成络盐 ,可增强蛋白质和固定相间的疏水作用。 相似文献
2.
要以胰岛素、细胞色素C、溶菌酶、转铁蛋白和肌红蛋白5种标准蛋白为研究对象,将6种浓度的标准蛋白在反相色谱(Waters Symmetry 300 C4、Waters Symmetry 300 C18、C8 HC)的保留时间非线性拟合(CSASS软件),获得了5种蛋白质在3种色谱柱的lnk=α+cCB方程,15个方程的回归系数均大于0.999,证实方程Ink=a+cCB可准确地描述蛋白质在反相色谱的保留规律.运用该方程可预测蛋白质在其它梯度条件下的保留时间,预测值和实验值的相对误差均小于5%.该方程还可用于蛋白质混合物的梯度分离的优化,20 min内可实现5种标准蛋白的基线分离. 相似文献
3.
盐酸胍对疏水色谱中蛋白质保留行为的影响 总被引:3,自引:0,他引:3
研究了变性剂酸胍对几种蛋白质在高效疏水色谱中保留行为的影响,用液相色谱中溶质的计量置换保留模型和测流动相表面张力及蛋白质紫外吸收光谱方法研究的结果表明:在低浓度范围内,盐酸胍主要以疏水作用影响蛋白质的保留;而在高浓度区域内,盐酸胍的存在则显著影响蛋白质分子的构象,使其保留行为发生变化。 相似文献
4.
5.
6.
液相色谱-质谱(LC-MS)联用是当今规模化蛋白质鉴定的主流技术。肽段在反相液相色谱(RPLC)中的保留时间主要是由肽段的理化性质和LC条件(固定相、流动相)决定的。可以通过分析肽段的理化性质,并量化它们对肽段色谱行为的影响来预测保留时间。预测结果可以用于帮助提高蛋白质鉴定的数量和可信度,也可用于肽段的翻译后修饰等研究。现在已有的保留时间预测算法主要有保留系数法和机器学习法两大类,得到的预测保留时间与实际保留时间相关系数可达到0.93。随着色谱和质谱技术的不断发展,肽段色谱行为的稳定性和重现性越来越好,保留时间预测结果也越来越准确。预测肽段保留时间将成为提高蛋白质鉴定结果的重要技术手段之一。 相似文献
7.
对蛋白质在离子交换柱上选择民性和非吸附特性进行了研究。蛋白质在有机磷酸锆阳离子色谱柱上,其保留作用随流动相pH值在离子强度的增加而减小;蛋白质在强阳离子和强阴离子色谱柱上的保留作用,即是流动相中的pH值等于蛋白质的等当点,其净电荷为零。不册蛋白质仍有不同程度的保留,这主要是由于蛋白质的三维结构使电荷 密度的大小和分布的不均匀以及离子交换填料表面性质的影响。 相似文献
8.
9.
用参数Z表征疏水色谱中脲浓度与蛋白质分子的构象变化 总被引:7,自引:1,他引:7
研究了5种标准蛋白在流动相中含有不同脲浓度条件下的疏水色谱保留行为。当脲浓度不变时,蛋白质的保留仍然服从计量置换保留模型,并可测定在该特定脲浓度条件下蛋白质的Z值。计量置换参数Z可作为疏水色谱中生物大分子的构象变化的表征。 相似文献
10.
11.
Gautam UG Gautam MP Sawada T Takafuji M Ihara H 《Journal of chromatography. A》2009,1216(16):3571-3577
With the successful implementation of poly(4-vinylpyridine)-grafted silica prepared by grafting-from approach (GF-VP(n)) as a stationary phase for the separation of polycyclic aromatic hydrocarbons (PAHs) in normal-phase HPLC, this paper describes the chromatographic retention behaviors of PAHs with GF-VP(n) in reversed-phase HPLC. Significantly higher retention factor along with enhanced shape selectivity were observed with GF-VP(n). Thermodynamic study on the retention behaviors of PAHs with GF-VP(n) in normal-phase and reversed-phase HPLC revealed that retention of PAHs was exothermic in both phases. Furthermore, higher entropic contribution was observed in reversed-phase HPLC compared to normal-phase HPLC. 相似文献
12.
Retention of nucleic acids in ion‐pair reversed‐phase high‐performance liquid chromatography depends not only on base composition but also on base sequence 下载免费PDF全文
Jun‐qin Qiao Chao Liang Lan‐chun Wei Zhao‐ming Cao Hong‐zhen Lian 《Journal of separation science》2016,39(23):4502-4511
The study on nucleic acid retention in ion‐pair reversed‐phase high‐performance liquid chromatography mainly focuses on size‐dependence, however, other factors influencing retention behaviors have not been comprehensively clarified up to date. In this present work, the retention behaviors of oligonucleotides and double‐stranded DNAs were investigated on silica‐based C18 stationary phase by ion‐pair reversed‐phase high‐performance liquid chromatography. It is found that the retention of oligonucleotides was influenced by base composition and base sequence as well as size, and oligonucleotides prone to self‐dimerization have weaker retention than those not prone to self‐dimerization but with the same base composition. However, homo‐oligonucleotides are suitable for the size‐dependent separation as a special case of oligonucleotides. For double‐stranded DNAs, the retention is also influenced by base composition and base sequence, as well as size. This may be attributed to the interaction of exposed bases in major or minor grooves with the hydrophobic alky chains of stationary phase. In addition, no specific influence of guanine and cytosine content was confirmed on retention of double‐stranded DNAs. Notably, the space effect resulted from the stereostructure of nucleic acids also influences the retention behavior in ion‐pair reversed‐phase high‐performance liquid chromatography. 相似文献
13.
A phenomenological approach was presented to describe the retention behaviors of solutes in capillary electrochromatography (CEC). Equations for calculation of the retention time and actual chromatographic retention factor for ionic solutes, weak monoprotic acid and weak monoprotic base were derived, which can be described by two general expressions regardless the charge status of the solute. The general expressions enable calculation of the retention time and retention factor in CEC from chromatographic and electrophoretic data, which were experimentally verified with a variety of compounds and a variety of CEC modes. Based on this approach, the chromatographic retention and the electrophoretic migration in the CEC systems studied were found to be two independent processes. The validity of this approach was also discussed. 相似文献
14.
Ching-Wei Tsai Wei-Hung Kao Li-Chiao Chang Ruoh-Chyu Ruaan Wen-Yih Chen 《Analytical and bioanalytical chemistry》2012,404(8):2437-2444
In this study, the relationship of the structural stability of peptide diastereomers in elution solvents and their retention behaviors in reversed-phase chromatography (RPC) was examined to provide guidance on the solvent selection for a better separation of peptide diastereomers. We investigated the chromatographic retention behaviors of exenatide, a peptide drug for the treatment of type II diabetes mellitus and its three diastereomers using RPC and implicit molecular dynamics (MD) simulation analysis. Three diastereomers involved in the single serine residue mutation of d-form at the 11th, 32nd, and 39th residues were investigated in this study. Results show that the order of the solution structural stability of exenatide and its diastereomers is consistent with their retention order by 36?% acetonitrile/water elution. The sample loading solvent also affects the retention behaviors of exenatide peptide diastereomers in RPC column. Furthermore, a larger solution conformation energy difference of the critical pair of exenatide and its diastereomer (d-Ser39) at the elution solvent of 32?% tetrahydrofuran/water were obtained by MD simulation, and baseline separation was proved experimentally. In summary, we demonstrated that the solution structural stability–chromatographic retention relationship could be a powerful tool for elution solvent selection in peptide chromatographic purification, especially valuable for the separation of critical pair of diastereomers. Figure
The structural stability and reversed-phase chromatography (RPC) retention relationship was investigated for a better chromatographic separation of peptides. Our results revealed that the rigid peptide with lower solution conformation energy exhibits a smaller retention factor in RPC column. Conversely, the flexible peptide with the higher solution conformation energy exhibits a larger retention factor. Based on this finding, we have examined that the baseline separation could be achieved by tuning the elution solvent composition to increase the structural stability difference between peptides. Consequently, the structural stability and RPC retention relationship could actually provide an important guidance on peptide separation. 相似文献
15.
A series of cellulose benzoates with different degrees of substitution (DS) were prepared by aminolysis under homogeneous conditions. Using them as a stationary phase, the dependence of the chromatographic chiral recognition of cellulose benzoate (CB) on its DS was studied under normal phase conditions. For most enantiomeric pairs, chiral recognition decreased along with the decrease in DS. However, some enantiomeric pairs were resolved only by CBs carrying unsubstituted hydroxyl groups. Many of the compounds were quite strongly retained by cellulose benzoate with a DS of 2.8. A study of the retention behaviors of simple achiral compounds led us to the conclusion that the change in the retention behaviors by introducing free hydroxyl groups into tribenzoate is not caused by hydrogen bonding including the hydroxyl groups, but by a specific unidentified change. 相似文献
16.
17.
Tatsuro Nakagama Atsutoshi Yamaguchi Kazuya Hirasawa Koji Yoshida Katsumi Uchiyama Toshiyuki Hobo 《Analytical sciences》2002,18(1):49-53
The photo-responses of the retention and enantioseparation of several optical isomers were evaluated using an azobenzene-modified gamma-cyclodextrin stationary phase (Az gamma-CDSP) in micro-HPLC. UV light irradiation induced a decrease in the retention and the chiral selectivity for N-(3,5-dinitrobenzoyl)-1-phenylethylamine (DNBPEA) and N-(3,5-dinitrobenzoyl)-1-(1-naphtylethyl)amine (DNBNEA), while an increase was induced for dansylphenylalanine (DnsPhe) using a mixture of methanol and aqueous phosphate buffer as the mobile phase. No changes in the retention and the enantiomer separation of benzoin were observed with UV light irradiation. The retention behaviors were recovered by visible-light irradiation. It was speculated that the main factor of the change in the retention behavior was a change in the pi-pi interaction due to the azobenzene moiety of the stationary phase with photo-irradiation. Comparing the retention behavior before and after UV light irradiation, a suitable condition for obtaining a better resolution and enantiomer separation would be chosen using Az gamma-CDSP. 相似文献
18.
Retention behaviors of pyrazine and alkylpyrazines on various stationary phases in reversed-phase liquid chromatography were examined. An abnormal temperature effect on the retention of alkylpyrazines with a mobile phase consisting of acetonitrile and water was observed when changing the column temperature. On the other hand, no similar trend was found with a methanol-water mobile phase. For all the columns investigated in this work, the above tendency to the temperature-dependence was consistently observed, suggesting that the abnormal temperature effect on the retention of alkylpyrazines could be mainly induced by an acetonitrile-based mobile phase. 相似文献
19.
20.
本文研究了杂多酸阴离子在正丁胺柠檬酸盐胶束液相色谱中的保留行为, 考察了胶束浓度,有机修饰剂种类和含量,柱温,pH 值等因素对杂多酸阴离子保留行为及柱效的影响,与反相离子对色谱比较,本体系具有柱效高等优点, 这对分离有较大分子量的杂多酸是有利的,运用此方法进行杂多酸定量分析,得到满意的结果 相似文献