Guangzhou Research and Creativity Biotechnology Ltd

Guangzhou, China

Guangzhou Research and Creativity Biotechnology Ltd

Guangzhou, China
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Qin Q.,South China Normal University | Zhang S.,National University of Singapore | Zhang W.-G.,South China Normal University | Zhang Z.-B.,South China Normal University | And 6 more authors.
Journal of Separation Science | Year: 2010

In this study, the CD derivative, mono (6A-azido-6 A-deoxy)-per(p-chlorophenylcarbamonylated) β-CD was chemically immobilized onto the surface of an aminofunctionalized silica gel with different pore (100, 300, and 500Å) and particle (3, 5, and 10 mm) sizes to obtain novel chiral stationary phases. The impact of pore and particle size on the amount of immobilized Ph-b-CD, column performance, and enantioselectivity was investigated by evaluating the separation of a variety of racemates in both the normal- and the reversed-phase modes. Experimental results revealed that the retention factor and resolution of racemates generally decreased with increasing pore size; the column prepared with the smallest (3 μm) silica gel particle size gave the best column performance and enantioselectivity in both the normal- and the reversed-phase modes. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.


Wang Q.,South China Normal University | Xiong Y.,South China Normal University | Lu B.,Guangzhou Research and Creativity Biotechnology Ltd. | Fan J.,South China Normal University | And 3 more authors.
Journal of Separation Science | Year: 2013

N-(2,4-dinitrophenyl)-proline and N-(2,4-dinitrophenyl)-serine were enantiomerically resolved on the BSA chiral stationary phase by HPLC in reversed-phase mode. Effects of chromatographic conditions on enantioseparation and elution order have been investigated in detail. For these two samples, reversal of enantiomer elution order was observed by changing buffer pH, the content of acetonitrile, or alcohol modifiers in mobile phase, which is firstly reported in the BSA chiral stationary phase studies. More interestingly, combined effect between buffer pH and the content of acetonitrile was also observed. In addition, coelution range of enantiomers varied along with the content of acetonitrile in mobile phase. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Fang Z.,South China Normal University | Fang Z.,East China Jiaotong University | Guo Z.,South China Normal University | Qin Q.,South China Normal University | And 4 more authors.
Journal of Chromatographic Science | Year: 2013

A direct semi-preparative high performance liquid chromatography (HPLC) enantioseparation of ofloxacin was performed on chemically immobilized cyclodextrin derivative-mono (6A-azido-6A-deoxy)-per(p-chlorophenyl carbamoylated) β-CD chiral stationary phase. Conditions for semi-preparative separations were established using a 250 × 4.6 mm i.d. column and subsequently extended to a 250 × 10.0 mm i.d. column that enabled separations on a milligram scale. Optimization of the chromatographic conditions (mobile phase and column load) with respect to better efficiency, resolution and peak retention resulted in a system capable of separating up to 304 mg of (-)-(S)-ooxacin and 56 mg of (+)-(R)-ooxacin of the racemate over 6 h. The purities of the separated enantiomers were determined by HPLC. Moreover, both separated enantiomers were characterized by mass spectrometry; then, the absolute configuration of the products was clearly confirmed by polarimetry. © The Author [2012]. Published by Oxford University Press. All rights reserved.


Fan Q.,South China Normal University | Zhang K.,South China Normal University | Tian L.-W.,Guangzhou Research and Creativity Biotechnology Ltd | Fan J.,South China Normal University | And 3 more authors.
Journal of Chromatographic Science | Year: 2014

A new cyclodextrin-derived chiral stationary phase (denoted as CDA-CSP) was synthesized by immobilizing mono(6A-azido-6A-deoxy)- per(p-chlorophenyl carbamoylated) β-cyclodextrin derivative to alkynyl modified silica via click chemistry. This newly prepared CSP shows good enantioseparation performance for six chiral compounds (1-6), such as 4-phenyl-oxazolidine-2-thione, two kinds of aryl alcohols, substituted flavonoids and benzoin, in which baseline separation of Analytes 1-4 was achieved under the experimental conditions. The effects of column temperature, mobile phase pH and content of methanol on the enantioseparation characteristics of CDA-CSP were investigated in detail. Retention factor and resolution for Compound 3 gradually reduced with an increase of column temperature, and a good linear relationship was shown between napierian logarithm of selectivity factor and reciprocal of column temperature. In the pH range from 3.56 to 5.50, a change in pH hardly affected the resolution of Analyte 2. In addition, increasing methanol in the mobile phase resulted in rapid eluting of the analytes from the column in reversed-phase mode. The retention factors for Analytes 1 and 3 significantly decreased and their resolution showed different trends. © The Author [2013]. Published by Oxford University Press. All rights reserved.


Lin C.,South China Normal University | Fan J.,South China Normal University | Liu W.-N.,South China Normal University | Tan Y.,Guangzhou Research and Creativity Biotechnology Co. | And 2 more authors.
Journal of Pharmaceutical and Biomedical Analysis | Year: 2014

Two new cyclodextrin-derived chiral stationary phases with multiple urea linkages were prepared through the Staudinger reactions between aminopropyl silica gel and cyclodextrin derivatives, namely, heptakis(6-azido-6-deoxy-2,3-di-O-3,5-dimethylphenylcarbamoylated)-β-cyclodextrin and heptakis(6-azido-6-deoxy-2,3-di-O-3,5-dichlorophenylcarbamoylated)-β-cyclodextrin, respectively. HPLC separation behaviors toward 46 chiral analytes have been investigated under multimodal elution. They exhibited good separation performances for these analytes and also showed some complimentary enantioselectivity to each other, due to different electron-donating (methyl)/withdrawing (chlorine) groups in the phenylcarbamate moieties. Among these analytes, aromatic alcohols and N-(2,4-dinitrophenyl)-derived carboxylic acids were better resolved on the π-basic chiral stationary phase than the π-acidic. The proton pump inhibitors, the 5-hydroxytryptamine receptor antagonists, and the analytes with carbonyl groups easily formed stereoselective interactions with the π-acidic chiral stationary phase, further leading to better enantioseparation. Elution order reversal for palonosetron and N-(2,4-dinitrophenyl) glutamine was observed in three chiral stationary phases, probably induced by the difference of phenylcarbamate groups. Moreover, mobile phase effects on retention behaviors of analytes have been studied in detail. © 2014 Elsevier B.V.


Liu W.-N.,South China Normal University | Fan J.,South China Normal University | Lin C.,South China Normal University | Zheng S.-R.,South China Normal University | And 2 more authors.
Journal of Chromatographic Science | Year: 2015

A new cyclosporine-bonded stationary phase has been synthesized through the Staudinger reaction between azido cyclosporine A (CsA) and aminopropyl silica gel and applied in separations of six disubstituted aromatic analytes by high-performance liquid chromatography. For dimethyl phthalate, nitroaniline and chloronitrobenzene, their positional isomers were well-separated on this CsA stationary phase, in which the separation factor for m-/o-dimethyl phthalates was the biggest. For nitrotoluene, dichlorobenzene and benzenediol, the m-/o-isomers were co-eluted. Then, effects of chromatographic conditions (such as types and content of alcoholic modifiers) on separation of nitroaniline positional isomers have been investigated. Retention behaviors of nitroaniline isomers on the column exhibited the strengthening trend along with increasing carbon number of alcohols, from ethanol to 1-propanol, and to 1-butanol. A similar phenomenon was observed by lowering the content of alcohol. © The Author 2014. Published by Oxford University Press.


Chen T.,South China Normal University | Chen X.,South China Normal University | Xu J.,Guangzhou Research and Creativity Biotechnology Co. | Fan J.,South China Normal University | And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2016

Due to some advantages such as high precision, high efficiency and low consumption of organic solvents, chromatographic separation technique by simulated moving bed (SMB) has attracted considerable attention in the past decades. Herein, the enantioseparation of metalaxyl racemate on EnantioPak OD columns has been carried out by SMB chromatography with the mixture of hexane-ethanol (70 :30, v / v). The elution order of two metalaxyl enantiomers under current chromatographic conditions was determined by HPLC with the optical rotation detector. Then, the influence of running parameters, such as the concentration, flow rate and switch time on the resolution of metalaxyl racemate has been studied in detail. In addition, the separation results from SMB and the preparative chromatography have been compared under the same concentrations. The results showed that the retention of S-(+)-metalaxyl was weaker than R-(-)-metalaxyl and S-(+)-metalaxyl was eluted first. Most importantly, metalaxyl racemate was well separated by SMB chromatography under linear or non-linear conditions, and the purity of each enantiomer product was over 99%. Furthermore, the amount separated by SMB was much more than by the preparative chromatography with racemate concentration of 15 mg / mL, and the mobile phase consumption was one-ninth of the latter. In brief, these results provide us important information for the future development of large-scale chromatographic separation of metalaxyl enantiomers. © 2016 Science Press.


Li L.,South China Normal University | Fan J.,South China Normal University | Zhang J.,South China Normal University | Chen X.,Guangzhou Research and Creativity Biotechnology Co. | And 4 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2016

Over the past decades, HPLC enantioseparation with chiral stationary phases (CSPs) has been widely applied in chiral analysis and preparation of new pharmaceuticals pesticides, food, etc. Herein, enantioseparation of 20 chiral compounds have been carried out on three polysaccharide-based CSPs (EnantioPak AD, AS and OD) with normal phases by HPLC, separately. The influences of skeletal structure and the kinds of derivative groups on separation behaviors of these CSPs have been studied in detail. As results indicated, except for compound 13, the other compounds were baseline separated on EnantioPak AD, with most of resolution over 2.0; in addition, better separation for acidic or basic compounds was achieved through adding acidic/basic additives into the mobile phase of hexane-alcohol. For four aromatic alcohols (compounds 13-16), their retention in the EnantioPak AD column showed a weakening tendency with increase of carbon number in side chain group, and the reverse trend of their resolution was observed. Furthermore, EnantioPak AD showed much better separation performance for eight compounds (13-20) than the others. In short, these results have provided some references for further investigation of separation behavior and applications of polysac-charide-based CSPs. © 2016 Science Press.


Zhang J.,South China Normal University | Chen X.,Guangzhou Research and Creativity Biotechnology Co. | Li L.,South China Normal University | He J.,South China Normal University | And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2016

Supercritical fluid chromatographic (SFC) technique has been widely applied in the analysis, determinations and chromatographic preparations of chiral compounds in past decades due to some advantages such as fast speed, high efficiency and low consumption of organic solvents. Herein, 24 kinds of chiral compounds (H1-H24) have been resolved on four polysaccharide-coated chiral stationary phases (CSPs) by SFC and high performance liquid chromatography (HPLC), separately. Taking into account their retention times and selection factors of these compounds, SFC separation showed a better efficiency than HPLC for most of the compounds, except for some axis-chiral compounds. Some complementarity between SFC and HPLC separations was observed. For H15-H17, their retentions in SFC separations showed a strengthening trend with increasing carbon numbers of side alkyl chain, whereas a reverse tendency in HPLC separation was displayed. Most interestingly, an elution order reversal of metconazole enantiomers was found in this work. In brief, these results would provide some valuable references for the development of SFC separation methods in the future.


PubMed | Guangzhou Research and Creativity Biotechnology Co. and South China Normal University
Type: | Journal: Journal of pharmaceutical and biomedical analysis | Year: 2014

Two new cyclodextrin-derived chiral stationary phases with multiple urea linkages were prepared through the Staudinger reactions between aminopropyl silica gel and cyclodextrin derivatives, namely, heptakis(6-azido-6-deoxy-2,3-di-O-3,5-dimethylphenylcarbamoylated)--cyclodextrin and heptakis(6-azido-6-deoxy-2,3-di-O-3,5-dichlorophenylcarbamoylated)--cyclodextrin, respectively. HPLC separation behaviors toward 46 chiral analytes have been investigated under multimodal elution. They exhibited good separation performances for these analytes and also showed some complimentary enantioselectivity to each other, due to different electron-donating (methyl)/withdrawing (chlorine) groups in the phenylcarbamate moieties. Among these analytes, aromatic alcohols and N-(2,4-dinitrophenyl)-derived carboxylic acids were better resolved on the -basic chiral stationary phase than the -acidic. The proton pump inhibitors, the 5-hydroxytryptamine receptor antagonists, and the analytes with carbonyl groups easily formed stereoselective interactions with the -acidic chiral stationary phase, further leading to better enantioseparation. Elution order reversal for palonosetron and N-(2,4-dinitrophenyl) glutamine was observed in three chiral stationary phases, probably induced by the difference of phenylcarbamate groups. Moreover, mobile phase effects on retention behaviors of analytes have been studied in detail.

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