Co-reporter:Ya-Li Song, Yun-Fang Dong, Fan Wu, Tao Yang, Geng-Liang Yang
Ultrasonics Sonochemistry 2015 Volume 22() pp:119-124
Publication Date(Web):January 2015
DOI:10.1016/j.ultsonch.2014.05.010
3-Hydroxy-5,5-dimethyl-2-[phenyl(phenylthio)methyl]cyclohex-2-enone is synthesized via one-pot three-component reactions of aromatic aldehyde, substituted thiophenol and 5,5-dimethyl-1,3-cyclohexanedione catalyzed by p-dodecylbenzene sulfonic acid (DBSA) under ultrasound. Under ultrasound irradiation the yields are much higher (sometimes substantially, by almost double) and the reaction time decreases substantially, the reaction conditions are milder. This method provides several advantages such as environment friendliness, high yields and simple work-up procedure and the protocol provides a novel alternative for the synthesis of thioether.
Co-reporter:Jing Zhong, Mengbei Hao, Ruo Li, Ligai Bai, Gengliang Yang
Journal of Chromatography A 2014 Volume 1333() pp:79-86
Publication Date(Web):14 March 2014
DOI:10.1016/j.chroma.2014.01.072
•A novel polymeric monolith was prepared by triallyl isocyanurate and trimethylolpropane triacrylate.•The column was successfully used as the stationary phases of HPLC and CLC, respectively.•Successfully separate the mixture of small molecules compounds by RP-HPLC.•The column performed 124,348 theoretical plates per meter for p-xylene.A new polymeric monolith was prepared in stainless-steel column and fused-silica capillary, respectively, by atom transfer radical polymerization technique. In the polymerization, triallyl isocyanurate (TAIC) was used as the functional monomer; trimethylolpropane triacrylate (TMPTA) as the crosslinking agent; polyethylene glycol 200 and 1,2-propanediol as the co-porogens; carbon tetrachloride as the initiator and ferrous chloride as the catalyst. The conditions of polymerization were optimized. Morphology of the prepared poly(TAIC-co-TMPTA) monolith was investigated by scanning electron microscopy; pore properties were assayed by mercury porosimetry and nitrogen adsorption. The characterization indicated that the prepared reversed-phase monolith possessed uniform structure, good permeability and mechanical stability. The column was used as the stationary phase of reversed phase high performance liquid chromatography (RP-HPLC) and capillary liquid chromatography (CLC) to separate the mixture of aromatic compounds. The new column performed around 125,000 theoretical plates per meter. The column showed good reproducibility: the relative standard deviation values of the retention factor values for aromatic compounds were less than 1.52% (n = 7, column-to-column).
Co-reporter:Lijuan Wang, Xiufeng Liu, Qienan Lu, Yanan Zou, Qi Liu, Juan Yang and Gengliang Yang
Analytical Methods 2014 vol. 6(Issue 12) pp:4107-4114
Publication Date(Web):09 May 2014
DOI:10.1039/C3AY42210K
Three amino alcohols, propranolol, clenbuterol and cycloclenbuterol, were enantioseparated on an achiral column by reversed-phase high performance liquid chromatography (RP-HPLC). A chiral chromatographic system was established based on C18-bonded silica gel as the support and a self-prepared di-n-butyl-L-tartrate–boric acid complex as the chiral mobile phase additive. In order to obtain better enantioseparations, the influences of di-n-butyl-L-tartrate and boric acid concentrations, the type, concentration and pH of the buffer, as well as methanol content were extensively investigated. It was found that the mobile phase composition played an important role in improving the enantioseparations and all of the enantiomers could be baseline resolved under the optimized experimental conditions. Three pairs of enantiomers, which could not be separated with only di-n-butyl-L-tartrate, obtained good chiral separations using the complex chiral selector. The primary driving forces responsible for the chiral recognition were assumed to be the ion-pair interaction between the enantiomers and the chiral selector; and the interactions between the ion-pairs above and the stationary phase also played important roles for the chiral separations in RP-HPLC.
Co-reporter:Mengbei Hao, Jing Zhong, Ruo Li, Haijing Li, Ligai Bai and Gengliang Yang
Analytical Methods 2014 vol. 6(Issue 8) pp:2655-2661
Publication Date(Web):16 Jan 2014
DOI:10.1039/C3AY41769G
A novel skeleton hydrophobic polymeric monolith was prepared by redox initiation in this paper. At ambient temperature, benzoyl peroxide (BPO) and N,N-dimethyl aniline (DMA) were used as initiators, 1-dodecene (C12) as the monomer and ethyleneglycol dimethacrylate as the cross linking agent. The polymerization conditions were optimized in order for use in chromatographic separations. The character of the monolith was investigated by scanning electron microscopy (SEM), fourier transform infrared spectroscopy, mercury porosimetry and nitrogen adsorption–desorption mercury porosimetry. Moreover, the prepared monolith was used as the stationary phase in high performance liquid chromatography to separate a mixture of benzenes in a hydrophobic chromatography mode. Baseline separations and high column efficiencies in excess of 11000 theoretical plates per meter were obtained.
Co-reporter:Ruo Li, Jing Zhong, Mengbei Hao, Ligai Bai and Gengliang Yang
Analytical Methods 2014 vol. 6(Issue 2) pp:589-595
Publication Date(Web):05 Nov 2013
DOI:10.1039/C3AY41532E
A porous functional polymer was prepared by in situ polymerization reaction. In this process, azobisisobutyronitrile was used as the initiator; hexanediol diacrylate (HDDA) and butyl methacrylate (BMA) as co-monomers; dodecyl alcohol as the porogenic solvent. The conditions of polymerization were optimized. The morphology of the polymer was investigated by scanning electron microscopy. Chemical groups in the monolith were assayed by infrared spectrometry. The pore size distribution was determined by mercury intrusion porosimetry and nitrogen adsorption–desorption. Finally, the functional polymer, a poly(HDDA-co-BMA-co-EDMA) monolith, was used as the stationary phase of high performance liquid chromatography (HPLC) to separate small molecules.
Co-reporter:Ya-Li Song, Yun-Fang Dong, Tao Yang, Chao-Chao Zhang, Li-Min Su, Xin Huang, Dong-Nuan Zhang, Geng-Liang Yang, Yu-Xin Liu
Bioorganic & Medicinal Chemistry 2013 Volume 21(Issue 24) pp:7624-7627
Publication Date(Web):15 December 2013
DOI:10.1016/j.bmc.2013.10.034
In an effort to develop potent anti-cancer chemopreventive agents that act on topoisomerase II, a novel series of bisindolylalkanes analogues such as 3,3′-(thiochroman-4,4-diyl)bis(1H-indole) are synthesized. Structures of all compounds are elucidated by 1H NMR, 13C NMR and HRMS. Anti-proliferative activities for all of these compounds are investigated by the method of MTT assay on 7 human cancer lines. Most of them showed antitumor activities in vitro, the half maximal inhibitory concentration (IC50) value is 7.798 μg/mL of 3a against MCF7. Compound 3a showed comparable topoisomerase II inhibitory activity to etoposide (VP-16) at 100 μM concentration. The rest of the compounds also showed varying degree topoisomerase II inhibitory activity.A kind of novel bisindolylalkanes analogue is synthesized. Most of them showed antitumor activities in vitro and varying degree topoisomerase II inhibitory activity.
Co-reporter:Gengliang Yang, Cuihong Yan, Ligai Bai, Jia Li and Yanhui Duan
Analytical Methods 2012 vol. 4(Issue 4) pp:1098-1104
Publication Date(Web):08 Mar 2012
DOI:10.1039/C2AY05708E
A strong cation exchange monolithic column was prepared by a single step in situ radical polymerization without further chemical modification for high performance liquid chromatography (HPLC). The novel monolithic column used vinyl ester resin as the monomer, ethylene glycol dimethacrylate (EDMA) as the cross linking agent, 2,2′-azobisisobutyronitrile (AIBN) as the initiating agent, NaHSO3 both as inorganic adjunct and coadunate initiator (L. G. Bai, H. Y. Liu, Y. K. Liu, J. Chromatogr. A, 2010, 1218, 100-106, and F. A. Zhang, C. L. Yu, X. H. Zhu, C. Wei, Polym. Adv. Technol., 2006, 17, 608–611). Moreover, NaHSO3 can supply sulfonic acid groups as cation exchangers for ion-exchange monolithic column. Polymerization conditions and separation conditions were optimized, and the structure properties of the monoliths were also investigated. In addition, the chromatographic performance of the monolith was evaluated through separating human serum albumin (HSA) from human plasma in conjunction with HPLC and the expected results were acquired. The effects of buffer concentration and pH on the separation of HSA were investigated. Furthermore, the monolith was used to separate the mixture of protein (hemoglobin and HSA) with good resolution.
Co-reporter:Junjie Ma, Gengliang Yang, Cuihong Yan, Yanzhao Gu, Ligai Bai, Yanhui Duan and Jia Li
Analytical Methods 2012 vol. 4(Issue 1) pp:247-253
Publication Date(Web):23 Nov 2011
DOI:10.1039/C1AY05572K
A novel hydroxyl functionalized organic–inorganic hybrid monolithic column for high performance liquid chromatography (HPLC) was synthesized viafree radical copolymerization with sonocation-assist, which could shorten the time of the sol–gel process. Vinyltrimethoxysilane (VTMS) was used as the monomer and vinyl ester resin was used as both the monomer and crosslinker. The conditions of preparation were investigated and the characteristics of the hybrid column were studied by SEM and Fourier transform infrared spectroscopy. The obtained column showed high permeability and low backpressure. The column was used to separate lysozyme from egg white in a short time (6 min) by HPLC, and benzene and its homologs were separated by the hybrid column. In addition, influences on the elution of lysozyme, such as the pH value and the buffer concentration, were studied. Additionally, the lysozyme separated by the hybrid column showed high biological activity, which was assayed by the method of turbidimetry.
Co-reporter:Ligai Bai, Gengliang Yang, Huan Lei, Yang Wang and Libin Bai
Analytical Methods 2012 vol. 4(Issue 9) pp:2948-2952
Publication Date(Web):27 Jun 2012
DOI:10.1039/C2AY25367D
A uniform porous functional polymer was prepared by reversible addition–fragmentation chain transfer (RAFT) polymerization. In the process, S,S′-bis (α,α′dimethyl acetic acid) trithiocarbonate was used as the RAFT agent, 2,2-azobis (2-methylpropionitrpionitrile) was used as the initiator; vinyl carboxylate and methyl methacrylate were used as co-monomers; dodecyl alcohol and methanol roles were co-porogens. Morphology of the monolith was confirmed by scanning electron microscopy (SEM). Functional groups in the monolith were assayed by infrared (IR) spectrometry and pore size distribution was determined by a mercury porosimeter. The functional polymer was used as an HPLC stationary phase directly to separate immunoglobulin G from human plasma successfully in a short time (7 min).
Co-reporter:Lijuan Wang;Qiaoling Guo;Juan Yang;Liya Zhang
Chromatographia 2012 Volume 75( Issue 3-4) pp:181-185
Publication Date(Web):2012 February
DOI:10.1007/s10337-011-2176-2
In this study, a self-prepared complex chiral selector, di-n-butyl d-tartrate-boric acid complex, by the reaction of di-n-butyl d-tartrate with boric acid in a running buffer was used as a chiral selector for the enantioseparation of three β-agonists including clenbuterol, cycloclenbuterol and tulobuterol by means of microemulsion electrokinetic chromatography (MEEKC). Three β-agonists were successfully enantioseparated using the chiral system, indicating that the di-n-butyl d-tartrate-boric acid complex was a useful chiral selector. The effects of di-n-butyl d-tartrate and sodium tetraborate concentration, surfactant concentration, cosurfactant, phosphate, buffer pH and composition, as well as applied voltage were extensively investigated to achieve a good enantioseparation. The di-n-butyl d-tartrate and sodium tetraborate concentration in the running buffer had great influence on the chiral resolution (Rs). Three β-agonists which could not be separated with only di-n-butyl d-tartrate, obtained good chiral separation using the complex chiral selector; among them, two pairs including clenbuterol and cycloclenbuterol could be baseline resolved in 7 min under optimized experimental conditions of 0.8% (w/v) di-n-butyl d-tartrate, 40 mM sodium tetraborate, 3.0% (w/v) Tween-20 and 60 mM sodium dihydrogen phosphate with 25 kV as running voltage. The results indicated that the method could be used for the enantioseparation of three β-agonists.
Co-reporter:Yanhui Duan;Haiyan Liu;Jia Li;Junjie Ma;Yanzhao Gu;Cuihong Yan
Chromatographia 2012 Volume 75( Issue 3-4) pp:87-93
Publication Date(Web):2012 February
DOI:10.1007/s10337-011-2169-1
A novel porous monolithic column was prepared by in situ free-radical polymerization in a 50 mm × 4.6 mm i.d. stainless steel column at 60 °C, which was in the presence of 2,2′-azobisisobutyronitrile (AIBN) as initiator, with N-isopropylacrylamide (NIPAAm) and methacrylic acid (MAA) as monomers, ethylene dimethacrylate (EDMA) as crosslinker, methanol and dodecanol as a porogenic solvent. The micrographs of monolithic column were characterized by scanning electron microscopy (SEM) and pore size distribution was determined by mercury intrusion porosimetry. The pressure drop across the columns was measured as a function of flow rate using water and methanol. The result showed that the monolithic columns had an excellent permeability and a high mechanical stability. Moreover, the influence of several parameters which were column temperature, mobile phase composition and flow rate was investigated in the separation of mixtures of nifedipine and nisoldipine. In addition, the effects of type and concentration of buffer on the elution of human plasma protein were investigated. The results showed that a better peak shape was obtained at higher temperature and larger flow rate on the monolithic column.
Co-reporter:Zhengyue Ma;Xinghua Zhang;Shikui Wang;Yang He;Beilei Li;Junjie Yang;Yuejuan Lu ;Jiewei Sun
Chinese Journal of Chemistry 2011 Volume 29( Issue 4) pp:757-764
Publication Date(Web):
DOI:10.1002/cjoc.201190153
Abstract
As epoxy functional group has high anticancer activity, α,β-epoxyketones were designed and synthesized as new anticancer agents, and their structures were confirmed by UV, 1H NMR, IR, MS technigeces and elemental analysis. Their in vitro anticancer activities were evaluated by MTT method and the results showed that the compound 4c exhibited good activity with IC50 of 17.8, 22.0 and 24.1 µg/mL against A-549, Hela and HepG2 cells, respectively. The dose of LD50 of the mice by intragastric administration was 1864.4 mg/kg. Therefore, the α,β-epoxyketones could potentially provide as new anticancer agents.
Co-reporter:Jing Yang;Haiyan Liu;Ligai Bai ;Qiaoxia Zhang
Journal of Applied Polymer Science 2011 Volume 119( Issue 1) pp:412-418
Publication Date(Web):
DOI:10.1002/app.32617
Abstract
Porous poly(vinyl ester) resin monolithic supports were first prepared by radical polymerization of the continuous phase of oil in water high-internal-phase emulsions. Vinyl ester (VE) resin was used as the monomer, ethylene glycol dimethacrylate was used as a crosslinker, and poloxamer 127 was used as the emulsifier in the emulsion polymerization. The prepared columns were evaluated by scanning electron microscopy, mercury intrusion porosimetry, and Fourier transform infrared spectroscopy to observe the morphological characteristics and confirm the absorbance based on the VE resin polymer. The obtained monolith showed not only higher column permeability but also lower back pressure and higher column efficiency. To investigate the absorption performance of the monolithic column, a maximum loading capacity experiment was also applied with lysozyme (Lys), and the results show that the maximum adsorption of the poly(vinyl ester) resin monolith was 1.579 mg/g. Moreover, the capabilities of separation on this column in conjunction with high-performance liquid chromatography were investigated. Immunoglobulin could be separated from human plasma and chicken egg yolk with high resolution within 4 min. Additionally, fast separation of two mode proteins (interleukin-18 and Lys) was achieved on the monolith within 2 min at the rate of 1445 cm/h, which demonstrated the potential of the poly(vinyl ester) resin monolith for the fast separation of proteins. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Co-reporter:Gengliang Yang, Ligai Bai, Cuihong Yan, Yanzhao Gu, Junjie Ma
Talanta 2011 Volume 85(Issue 5) pp:2666-2672
Publication Date(Web):15 October 2011
DOI:10.1016/j.talanta.2011.08.048
A strong cation-exchange poly(vinyl carboxylate-co-ethyleneglycol dimethacrylate) (poly(VC-co-EDMA)) monolithic column for high performance liquid chromatography (HPLC) has been prepared firstly by atom transfer radical polymerization (ATRP) without the expensive complexing ligand, in which vinyl carboxylate was used as the monomer, ethyleneglycol dimethacrylate as the cross linking agent, carbon tetrachloride as the initiator and ferrous chloride as the catalyst. Conditions of the polymerization have been studied and optimized. Morphology of monolithic materials was studied by scanning electronic microscopy. Chemical groups of the monolith were assayed by infrared spectra method and the pore size distribution was determined by a mercury porosimeter. Moreover, the monolith was modified to bear strong-cation exchange groups and tested on the separation of human immune globulin G (IgG) from human plasma in conjunction with HPLC. Good resolution was obtained in a short time (10 min) in the separation. The effects of pH and buffer concentration on the elution of IgG have been investigated. Moreover, frontal analytical method was used to get the IgG dynamic banding capacity of the monolith that was 3.0 mg g−1. Besides, the monolith was also used to separate lysozyme from egg white and separate the mixture of papain, snailase and IgG.Highlights► Strong cation exchange monolith was prepared by ATRP. ► The ATRP process was realized without complexing ligand. ► The novel technique led a more uniform structure. ► The monolith was used to separate IgG and Lys with good resolution. ► The dynamic binding capacity of the monolith was much higher than that of the previous.
Co-reporter:Haiyan Liu, Mingquan Liu, Ligai Bai, Suying Sun, Yankun Liu, Gengliang Yang
Talanta 2011 Volume 85(Issue 2) pp:1193-1198
Publication Date(Web):15 August 2011
DOI:10.1016/j.talanta.2011.05.034
A thermo-responsive and macroporous monolithic cryogel was directly prepared by in situ free-radical redox cryo-polymerization in a stainless steel chromatographic column (100 mm × 4.6 mm i.d.) using N-isopropylacrylamide (NIPAAm) as functional monomer and PEG-20,000 as porogen at −12 °C. The internal morphology of resulting monolithic cryogel was estimated by scanning electron microscopy (SEM). Based on that, a submicron skeleton structure was observed. Besides, the gravimetrically determined rates of swelling/deswelling for thermo-responsive monolithic cryogel were much higher than that of hydrogel adopting the same component proportion via conventional method (25 °C for 24 h). Simultaneously, a temperature-dependent resolution of steroids was also achieved using only water as a mobile phase. The theoretical plate number of every analyte was more than 2000.
Co-reporter:Mingquan Liu;Haiyan Liu;Ligai Bai;Yankun Liu;Jia Cheng
Journal of Materials Science 2011 Volume 46( Issue 14) pp:4820-4825
Publication Date(Web):2011 July
DOI:10.1007/s10853-011-5392-0
In the past few years, polymer-based adsorbents have been emerging as highly effective alternatives to activated carbons for pollutants removal and recovery from industrial effluents. In this article, novel thermosensitive poly(N-isopropylacrylamide) (PNIPAAm) cryogels adsorbents were directly prepared with N-isopropylacrylamide (NIPAAm) as a thermosensitive monomer and PEG-20,000 as a porogen at −12 °C by means of an in situ free-radical redox cryopolymerization. Subsequently, PNIPAAm cryogels were further employed to adsorb and desorb melamine through temperature swing adsorption (TSA) between 25 and 50 °C. The adsorption isotherms were correlated to Langmuir and Freundlich isotherm models. Moreover, the result indicated that the developed PNIPAAm cryogels adsorbents could be utilized effectively to concentrate melamine from aqueous solutions and spiked liquid milk. The cycle of the adsorption and desorption could be repeated without much loss of the melamine adsorbing ability.
Co-reporter:Jing Yang;Haiyan Liu;Ligai Bai ;Qiaoxia Zhang
Chinese Journal of Chemistry 2010 Volume 28( Issue 2) pp:229-234
Publication Date(Web):
DOI:10.1002/cjoc.201090058
Abstract
A novel porous polymeric monolithic column based on poly(high internal phase emulsion) methacrylate monolith was prepared and applied to fast separation of proteins. The block copolymer chemistry of high internal phase emulsions was used in the experiment. These unique properties, together with high porosity, good mechanical property, chemical modification of the surface make themselves superior in monolithic medium applications. Morphology of the monolithic material was studied by scanning electron microscopy. The stability of the emulsion and the load of hydroxyl groups–the active group of the monolithic column were investigated. Additionally, the capabilities of separation of this column in conjunction with high performance liquid chromatography (HPLC) were investigated. Immunoglobulin was separated from human plasma and chicken egg yolk with high resolution on the hydrophobic interaction chromatographic column in a short time. The effects of pH and concentration of mobile phase (buffer) on the elution of immunoglobulin were investigated. Moreover, fast separation of a two mode protein mixture (α-amylase and lysozyme) on the monolith was achieved within 1.5 min at a velocity of 1445 cm·h−1. As a result, good separation was achieved, and stable low back pressure drop was ensured at high throughput elution with an even longer column.
Co-reporter:Li Qi
Journal of Separation Science 2009 Volume 32( Issue 18) pp:
Publication Date(Web):
DOI:10.1002/jssc.200900328
Abstract
A novel method of chiral ligand-exchange CE was developed with L-amino acylamides as a chiral ligand and zinc(II) as a central ion. It has been demonstrated that these chiral complexes, such as Zn(II)-L-alaninamide, Zn(II)-L-prolinamide, and Zn(II)-L-phenylalaninamide, are suitable for use as chiral selectors for the enantioseparation of either individual pair of or mixed dansyl amino acids. The optimal separation running buffer consisted of 5 mM ammonium acetate, 100 mM boric acid, 4 mM ZnSO4·7 H2O, and 8 mM L-amino acylamides at pH 8.2. The experiments showed that apart from the effect of the concentration of the complexes on the resolution and the migration time, the buffer pH also had a sharp influence on resolution. The employed chiral ligands exhibited different enantioselectivities and enantiomer migration orders. D-Amino acids migrate faster than L-amino acids when Zn(II)-L-alaninamide and Zn(II)-L-phenylalaninamide are used as chiral selectors, but it was observed that the migration order is reversed when Zn(II)-L-prolinamide is used as the chiral selector. Furthermore, the amount of dansylated amino acids is found to be highly dependent on the labeling temperature.
Co-reporter:Guanqun YANG;Haiyan LIU;Ligai BAI;Xiaojuan FENG;Xinru YANG
Chinese Journal of Chemistry 2009 Volume 27( Issue 4) pp:777-780
Publication Date(Web):
DOI:10.1002/cjoc.200990129
Abstract
Using vinyl ester resin both as the monomer and the crosslinker, 2,2-azobis(2-methylpropionitrile) (AIBN) as initiator, poly(vinyl ester resin) monolithic column was prepared to separate the immunoglobulin G (IgG) and yolk of eggs (IgY) from human plasma and egg yolk by HPLC respectively. The influence of concentration and pH of mobile phase on the chromatographic performance was investigated. Scanning electron microcopy showed that the poly(vinyl ester resin) monolithic stationary phase had a through-pore structure. Dynamic capacity of IgG on the polymeric monolithic column was investigated. The monolithic column had good flow-through properties and high resolution. The maximum adsorptive amount of IgG was 144 µg·g−1.
Co-reporter:ChunLiang Wei;Chuang Shang;LanDi Guo
Science Bulletin 2009 Volume 54( Issue 12) pp:2033-2037
Publication Date(Web):2009 June
DOI:10.1007/s11434-009-0186-3
Biomembrane-coated capillaries are prepared by coating different kinds of biomembranes including mice red cell membrane, human red cell membrane and S-180 cell membrane on the inner surface of the capillary, respectively. Effects of immobilized biomembrane amount, pH and biomembrane species on the interactions between drugs and biomembranes have been evaluated. The results showed that the chromatographic retention factor for each drug was essentially related to the amount of immobilized biomembrane, the pH and the type of biomembrane.
Co-reporter:Xiaojuan Feng;Haiyan Liu;Bingnan Ren;Xinru Yang
Chromatographia 2009 Volume 69( Issue 5-6) pp:403-407
Publication Date(Web):2009 March
DOI:10.1365/s10337-008-0904-z
A monolithic column, prepared from a vinyl ester resin used as both monomer and cross-linking agent, has been used to remove matrix compounds from biological fluid. Using this column, nisoldipine in human plasma samples could be enriched online and the protein could be eluted. For this method of extraction, response (peak area) was a linear function of concentration in the range 2–80 ng mL−1, with a linear regression coefficient of 0.99985. The limit of detection for nisoldipine in plasma was 1.2 ng mL−1. For nisoldipine at concentrations of 10, 30, and 70 ng mL−1 RSD were 4.33, 6.63, and 4.57%, respectively. Recovery for both extraction (>73.6%) and the entire analytical method (>90.7%) were acceptable for screening of plasma for nisoldipine. The 12-hour pharmacokinetic profile of nisoldipine in mice after oral administration (0.3 mg kg−1) was investigated. The results indicated the method could be used for therapeutic monitoring of nisoldipine and enabled simple and rapid assay of the drug in plasma.
Co-reporter:Geng-Liang YANG;Li-Gai BAI;Hai-Yan LIU;Yu ZHAO;Feng-Xin LI;Wei-Min CAO
Chinese Journal of Chemistry 2008 Volume 26( Issue 11) pp:2063-2066
Publication Date(Web):
DOI:10.1002/cjoc.200890368
Co-reporter:Gengliang Yang;Fengxin Li;Lijuan Wang;Kyung Ho Row;Haiyan Liu
Chromatographia 2008 Volume 68( Issue 1-2) pp:27-31
Publication Date(Web):2008 July
DOI:10.1365/s10337-008-0663-x
Monolithic silica columns were prepared via a sol–gel process using tri-block copolymer Pluronic F127 as structure-directing reagent. In this reaction, F127 induced phase separation but also acted as a template leading to a continuous structure of silica skeletons and textural pores as well as the formation of mesopores. The morphology of the monolithic materials was studied by scanning electron microscopy. The capability of separation and loading on this column were demonstrated. Phosphatidylcholine was separated from soy lecithin, demonstrating fast and efficient performance when the column was used for normal phase liquid chromatography.
Co-reporter:
Analytical Methods (2009-Present) 2014 - vol. 6(Issue 8) pp:NaN2661-2661
Publication Date(Web):2014/01/16
DOI:10.1039/C3AY41769G
A novel skeleton hydrophobic polymeric monolith was prepared by redox initiation in this paper. At ambient temperature, benzoyl peroxide (BPO) and N,N-dimethyl aniline (DMA) were used as initiators, 1-dodecene (C12) as the monomer and ethyleneglycol dimethacrylate as the cross linking agent. The polymerization conditions were optimized in order for use in chromatographic separations. The character of the monolith was investigated by scanning electron microscopy (SEM), fourier transform infrared spectroscopy, mercury porosimetry and nitrogen adsorption–desorption mercury porosimetry. Moreover, the prepared monolith was used as the stationary phase in high performance liquid chromatography to separate a mixture of benzenes in a hydrophobic chromatography mode. Baseline separations and high column efficiencies in excess of 11000 theoretical plates per meter were obtained.
Co-reporter:
Analytical Methods (2009-Present) 2012 - vol. 4(Issue 1) pp:NaN253-253
Publication Date(Web):2011/11/23
DOI:10.1039/C1AY05572K
A novel hydroxyl functionalized organic–inorganic hybrid monolithic column for high performance liquid chromatography (HPLC) was synthesized viafree radical copolymerization with sonocation-assist, which could shorten the time of the sol–gel process. Vinyltrimethoxysilane (VTMS) was used as the monomer and vinyl ester resin was used as both the monomer and crosslinker. The conditions of preparation were investigated and the characteristics of the hybrid column were studied by SEM and Fourier transform infrared spectroscopy. The obtained column showed high permeability and low backpressure. The column was used to separate lysozyme from egg white in a short time (6 min) by HPLC, and benzene and its homologs were separated by the hybrid column. In addition, influences on the elution of lysozyme, such as the pH value and the buffer concentration, were studied. Additionally, the lysozyme separated by the hybrid column showed high biological activity, which was assayed by the method of turbidimetry.
Co-reporter:Ligai Bai, Gengliang Yang, Huan Lei, Yang Wang and Libin Bai
Analytical Methods (2009-Present) 2012 - vol. 4(Issue 9) pp:NaN2952-2952
Publication Date(Web):2012/06/27
DOI:10.1039/C2AY25367D
A uniform porous functional polymer was prepared by reversible addition–fragmentation chain transfer (RAFT) polymerization. In the process, S,S′-bis (α,α′dimethyl acetic acid) trithiocarbonate was used as the RAFT agent, 2,2-azobis (2-methylpropionitrpionitrile) was used as the initiator; vinyl carboxylate and methyl methacrylate were used as co-monomers; dodecyl alcohol and methanol roles were co-porogens. Morphology of the monolith was confirmed by scanning electron microscopy (SEM). Functional groups in the monolith were assayed by infrared (IR) spectrometry and pore size distribution was determined by a mercury porosimeter. The functional polymer was used as an HPLC stationary phase directly to separate immunoglobulin G from human plasma successfully in a short time (7 min).
Co-reporter:Gengliang Yang, Cuihong Yan, Ligai Bai, Jia Li and Yanhui Duan
Analytical Methods (2009-Present) 2012 - vol. 4(Issue 4) pp:
Publication Date(Web):
DOI:10.1039/C2AY05708E
Co-reporter:
Analytical Methods (2009-Present) 2014 - vol. 6(Issue 2) pp:NaN595-595
Publication Date(Web):2013/11/05
DOI:10.1039/C3AY41532E
A porous functional polymer was prepared by in situ polymerization reaction. In this process, azobisisobutyronitrile was used as the initiator; hexanediol diacrylate (HDDA) and butyl methacrylate (BMA) as co-monomers; dodecyl alcohol as the porogenic solvent. The conditions of polymerization were optimized. The morphology of the polymer was investigated by scanning electron microscopy. Chemical groups in the monolith were assayed by infrared spectrometry. The pore size distribution was determined by mercury intrusion porosimetry and nitrogen adsorption–desorption. Finally, the functional polymer, a poly(HDDA-co-BMA-co-EDMA) monolith, was used as the stationary phase of high performance liquid chromatography (HPLC) to separate small molecules.
Co-reporter:
Analytical Methods (2009-Present) 2014 - vol. 6(Issue 12) pp:
Publication Date(Web):
DOI:10.1039/C3AY42210K
Three amino alcohols, propranolol, clenbuterol and cycloclenbuterol, were enantioseparated on an achiral column by reversed-phase high performance liquid chromatography (RP-HPLC). A chiral chromatographic system was established based on C18-bonded silica gel as the support and a self-prepared di-n-butyl-L-tartrate–boric acid complex as the chiral mobile phase additive. In order to obtain better enantioseparations, the influences of di-n-butyl-L-tartrate and boric acid concentrations, the type, concentration and pH of the buffer, as well as methanol content were extensively investigated. It was found that the mobile phase composition played an important role in improving the enantioseparations and all of the enantiomers could be baseline resolved under the optimized experimental conditions. Three pairs of enantiomers, which could not be separated with only di-n-butyl-L-tartrate, obtained good chiral separations using the complex chiral selector. The primary driving forces responsible for the chiral recognition were assumed to be the ion-pair interaction between the enantiomers and the chiral selector; and the interactions between the ion-pairs above and the stationary phase also played important roles for the chiral separations in RP-HPLC.
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