Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Base de dados
Tipo de documento
Assunto da revista
País de afiliação
Intervalo de ano de publicação
1.
Mikrochim Acta ; 189(9): 360, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042107

RESUMO

A spherical chiral porous organic polymer (POPs) COP-1 is synthesized by the Friedel-Crafts alkylation reaction of Boc-3-(4-biphenyl)-L-alanine (BBLA) and 4,4'-bis(chloromethyl)-1,1'-biphenyl (BCMBP), which was used as a novel chiral stationary phase (CSPs) for mixed-mode high-performance liquid chromatography (HPLC) enantioseparation. The racemic compounds were resolved in normal-phase liquid chromatography (NPLC) using n-hexane/isopropanol as mobile phase and reversed-phase liquid chromatography (RPLC) using methanol/water as mobile phase. The COP-1-packed column exhibited excellent separation performance toward various racemic compounds including alcohols, amines, ketones, esters, epoxy compounds, organic acids, and amino acids in NPLC and RPLC modes. The effects of analyte mass and column temperature on the separation efficiency of racemic compounds were investigated. In addition, the chiral resolution ability of the COP-1-packed column not only can be complementary in RPLC/NPLC modes but also exhibit a good chiral recognition complementarity with Chiralpak AD-H column and chiral porous organic cage (POC) NC1-R column. The relative standard deviations (RSD) (n = 5) of the retention time, resolution value, and peak area by repeated separation of 1-(4-chiorophenyl)ethanol are all below 3.0%. The COP-1 column shows high column efficiency (e.g., 17,320 plates m-1 for 1-(4-chlorophenyl)ethanol on COP-1 column in NPLC), high enantioselectivity, and good reproducibility toward various racemates. This work demonstrates that chiral POPs microspheres are promising chiral materials for HPLC enantioseparation.


Assuntos
Aminas , Polímeros , Cromatografia Líquida de Alta Pressão/métodos , Etanol , Porosidade , Reprodutibilidade dos Testes , Estereoisomerismo
2.
Molecules ; 24(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682770

RESUMO

Porous organic cages (POCs) have attracted extensive attention due to their unique structures and tremendous application potential in numerous areas. In this study, an enantioselective potentiometric sensor composed of a polyvinyl chloride (PVC) membrane electrode modified with CC3-R POC material was used for the recognition of enantiomers of 2-amino-1-butanol. After optimisation, the developed sensor exhibited enantioselectivity toward S-2-amino-1-butanol ( log K S , R P o t = -0.98) with acceptable sensitivity, and a near-Nernstian response of 25.8 ± 0.3 mV/decade within a pH range of 6.0⁻9.0.


Assuntos
Amino Álcoois/química , Técnicas Eletroquímicas , Eletrodos , Concentração de Íons de Hidrogênio , Membranas Artificiais , Estrutura Molecular , Cloreto de Polivinila/química , Porosidade , Potenciometria , Sensibilidade e Especificidade , Estereoisomerismo
3.
Electrophoresis ; 38(19): 2513-2520, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28678407

RESUMO

Natural amino acids are well known to form coordination polymers with transition metal ions. In this study, six homochiral metal-organic frameworks constructed from Zn2+ or Co2+ ions and various enantiopure amino acid (L-tyrosine, L-histidine, L-tryptophan and L-glutamic acid), namely [Zn(L-tyr)]n (L-tyrZn), [Zn4 (btc)2 (Hbtc)(L-His)2 (H2 O)4 ]·1.5H2 O, {[Zn2 (L-trp)2 (bpe)2 (H2 O)2 ]·2H2 O·2NO3 }n , [Co2 (L-Trp)(INT)2 (H2 O)2 (ClO4 )], [Co2 (sdba)((L-Trp)2 ] and [Co(L-Glu)(H2 O)·H2 O]∞ , were synthesized according to the methods previously reported in the literature. The six homochiral MOFs were explored as the chiral stationary phases for high-performance liquid chromatographic separation of enantiomers using hexane/isopropanol or hexane/dichloromethane as mobile phase. Various types of enantiomers such as alcohols, amines, ketones, ethers, organic acids, etc. can be resolved on these homochiral MOF columns. The results revealed that the enantioseletivities of homochiral MOFs based on amino acids as chiral bridging ligands used as stationary phases are practical in HPLC.


Assuntos
Aminoácidos/química , Cromatografia Líquida de Alta Pressão/métodos , Estruturas Metalorgânicas/química , Polímeros/química , 2-Propanol/química , Álcoois/isolamento & purificação , Aminas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/instrumentação , Éteres/isolamento & purificação , Hexanos/química , Cetonas/isolamento & purificação , Cloreto de Metileno/química , Estereoisomerismo
4.
Anal Chem ; 86(19): 9595-602, 2014 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-25188539

RESUMO

Chiral nematic mesoporous silica (CNMS) has attracted widespread attention due to some unique features, such as its nematic structure, chirality, large pore size, high temperature resistance, low cost, and ease of preparation. We first reported the use of CNMS as a stationary phase for capillary gas chromatography (GC). The CNMS-coated capillary column not only gives good selectivity for the separation of linear alkanes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), and isomers but also offers excellent enantioselectivity for chiral compounds. Compared with enantioseparations on commercial ß-DEX 120 and Chirasil-l-Val columns, a CNMS-coated capillary column offers excellent enantioselectivity, chiral recognition complementarity, and the separation of analytes within short elution times. It can also be potentially applied in high-temperature GC at more than 350 °C. This work indicates that CNMS could soon become very attractive for separations.


Assuntos
Celulose/química , Cromatografia Gasosa/métodos , Compostos Inorgânicos/química , Cristalização , Microscopia Eletrônica de Varredura , Difração de Pó , Estereoisomerismo
5.
Appl Microbiol Biotechnol ; 96(6): 1539-50, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22797600

RESUMO

To develop a high efficiency Candida antarctica lipase B (CALB) yeast display system, we linked two CALB genes fused with Sacchromyces cerevisiae cell wall protein genes, the Sed1 and the 3'-terminal half of Sag1, separately by a 2A peptide of foot-and-mouth disease virus (FMDV) in a single open reading frame. The CALB copy number of recombinant strain KCSe2ACSa that harbored the ORF was identified, and the quantity of CALB displayed on the cell surface and the enzyme activity of the strain were measured. The results showed that the fusion of multiple genes linked by 2A peptide was translated into two independent proteins displayed on the cell surface of stain KCSe2ACSa. Judging from the data of immunolabeling assay, stain KCSe2ACSa displayed 94 % CALB-Sed1p compared with stain KCSe1 that harbored a single copy CALB-Sed1 and 64 % CALB-Sag1p compared with stain KCSa that harbored a single copy CALB-Sag1 on its surface. Besides, strain KCSe2ACSa possessed 170 % hydrolytic activity and 155 % synthetic activity compared with strain KCSe1 as well as 144 % hydrolytic activity and 121 % synthetic activity compared with strain KCSa. Strain KCSe2ACSa even owned 124 % hydrolytic activity compared with strain KCSe2 that harbored two copies CALB-Sed1. The heterogeneous glycosylphosphatidylinositol-anchored proteins co-displaying yeast system mediated by FMDV 2A peptide was shown to be an effective method for improving the efficiency of enzyme-displaying yeast biocatalysts.


Assuntos
Vírus da Febre Aftosa/genética , Proteínas Fúngicas/genética , Lipase/genética , Peptídeos/genética , Pichia/genética , Engenharia de Proteínas/métodos , Candida/enzimologia , Candida/genética , Vírus da Febre Aftosa/metabolismo , Proteínas Fúngicas/metabolismo , Expressão Gênica , Lipase/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Peptídeos/metabolismo , Pichia/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
6.
J Chromatogr A ; 1426: 174-82, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26632517

RESUMO

Porous solids composed of shape-persistent organic cage molecules have attracted considerable attention due to their important applications such as molecular separation, heterogeneous catalysis, and gas storage. In this study, an imine-linked porous organic cage (POC) CC10 diluted with a polysiloxane OV-1701 was explored as a novel stationary phase for high-resolution gas chromatography (GC). A wide variety of enantiomers belonging to different classes of organic compounds have been resolved on the coated capillary column, including chiral alcohols, esters, ketones, ethers, halohydrocarbons, epoxides, and organic acids. The fabricated column complements to commercial ß-DEX 120 column and our recently reported CC3-R column for separating enantiomers, which indicates that the excellent chiral recognition ability of CC10 is not only interesting academically, but also has potential for practical application. In addition, CC10 also exhibits good selectivity for the separation of n-alkanes, n-alcohols, Grob mixture, and positional isomers. This work also indicates that this type of chiral POCs will become a new class of chiral selector in the near future.


Assuntos
Iminas/química , Compostos Macrocíclicos/química , Compostos Orgânicos/isolamento & purificação , Cromatografia Gasosa/métodos , Porosidade , Siloxanas , Estereoisomerismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA