A novel gradient pressurized capillary electrochromatography (pCEC) instrument was developed to separate peptides. Two gradient elution modes, hydrophobic and hydrophilic interaction mode in pCEC, were performed on t...A novel gradient pressurized capillary electrochromatography (pCEC) instrument was developed to separate peptides. Two gradient elution modes, hydrophobic and hydrophilic interaction mode in pCEC, were performed on this instrument. Baseline separation of six peptides was obtained on two gradient modes with C18 column and strong cationic exchange column respectively. The effects of mixer volume and total flow rate of pumps on resolution were also discussed.展开更多
Capillary electrochromatography (CEC) is a hybrid technique that couples the good selectivity of high-performance liquid chromatography (HPLC) and the high separation efficiency of capillary electrophoresis (CE)...Capillary electrochromatography (CEC) is a hybrid technique that couples the good selectivity of high-performance liquid chromatography (HPLC) and the high separation efficiency of capillary electrophoresis (CE). Both charged and uncharged compounds can be separated effectively using CEC. In some cases, however, the bubbles that generated in the capillary column in pure CEC performed on commercial CE instruments will cause unstable current and even disrupt the separation when the concentration of buffer is very high. By applying pressure on the electrochromatographic separation via a micro-HPLC pump, pressurized capillary electrochromatography ( pCEC ) combines two driving factors of the electroosmotic flow (EOF) and the pressure flow, thereby increasing the speed and the selectivity of separation and suppressing the bubble formation. Moreover,展开更多
A novel pressurized capillary electrochromatography (PCEC) was developed to separate basic drugs on strong cation exchange (SCX) column. The separation result by using PCEC was better than that by using micro-HPLC. Th...A novel pressurized capillary electrochromatography (PCEC) was developed to separate basic drugs on strong cation exchange (SCX) column. The separation result by using PCEC was better than that by using micro-HPLC. The effects of electrical field and pressure on plate height and resolution were investigated. Influences of organic modifier, ionic strength and pH value of buffer on retention behavior were evaluated, and the separation mechanism was also discussed.展开更多
Capillary columns are used in both capillary liquid chromatography and capillary electrochromatography. The design for capillary liquid chromatography is discussed in comparison with capillary gas chromatography. The ...Capillary columns are used in both capillary liquid chromatography and capillary electrochromatography. The design for capillary liquid chromatography is discussed in comparison with capillary gas chromatography. The difference of diffusion coefficient in gas and liquid phase is a key role. The study for obtaining a high performance capillary liquid chromatography is discussed. Capillary electrochromatography is recently interesting for its instinct ability to realize a high performance chromatography. Capillary electrochromatography with and without pressurized flow is reviewed briefly. Instrumentation for capillary electrochromatography with pressurized flow is discussed. The port of splitting, and gradient elution of both solution and potential are described. The new findings of both the variation of column resistance and capacity factor according to the value of applied electric voltage are also discussed.展开更多
A novel monolithic stationary phase with long alkyl chain ligands was introduced and evaluated in pressurized capillary electrochromatography(p-CEC) by using a mixture of neutral and charged compounds. The capillary m...A novel monolithic stationary phase with long alkyl chain ligands was introduced and evaluated in pressurized capillary electrochromatography(p-CEC) by using a mixture of neutral and charged compounds. The capillary monolithic-column was prepared by in situ copolymerization of ethylene dimethacrylate,alkyl alcohol and 2-acrylamido-2-methyl-1-propanesulfonic acid in a quadruple porogenic solvent consisting of 1,4-butanediol/cyclohexanol/docecanol/water. Effects of experimental parameters in p-CEC,such as pressure and electrical field strength,on the separation were investigated. The baseline separation of the components in the mixture was achieved. The monolithic column can be used as an alternative to the conventional capillary column such as the reversed phase ODS.展开更多
基金The study is supported by NNSFC,grant No.20175010.
文摘A novel gradient pressurized capillary electrochromatography (pCEC) instrument was developed to separate peptides. Two gradient elution modes, hydrophobic and hydrophilic interaction mode in pCEC, were performed on this instrument. Baseline separation of six peptides was obtained on two gradient modes with C18 column and strong cationic exchange column respectively. The effects of mixer volume and total flow rate of pumps on resolution were also discussed.
基金Supported by the National Natural Science Foundation of China(Nos 20305004 and 20575012), Program for NewCentury Ex-cellent Talents in University of China(No NCET-04-0612), Specialized Research Fund for the Doctoral Program of Higher Education(No 20050386008), and the Science Foundation of Fujian Province(Nos 2005Y015 and D0510006)
文摘Capillary electrochromatography (CEC) is a hybrid technique that couples the good selectivity of high-performance liquid chromatography (HPLC) and the high separation efficiency of capillary electrophoresis (CE). Both charged and uncharged compounds can be separated effectively using CEC. In some cases, however, the bubbles that generated in the capillary column in pure CEC performed on commercial CE instruments will cause unstable current and even disrupt the separation when the concentration of buffer is very high. By applying pressure on the electrochromatographic separation via a micro-HPLC pump, pressurized capillary electrochromatography ( pCEC ) combines two driving factors of the electroosmotic flow (EOF) and the pressure flow, thereby increasing the speed and the selectivity of separation and suppressing the bubble formation. Moreover,
基金theNationalNaturalScienceFoundationofChina (No .2 0 175 0 10 )the 14thNationalKeyLaboratoryOpeningFounda ionofChina (No .2 0 12 0 3 )
文摘A novel pressurized capillary electrochromatography (PCEC) was developed to separate basic drugs on strong cation exchange (SCX) column. The separation result by using PCEC was better than that by using micro-HPLC. The effects of electrical field and pressure on plate height and resolution were investigated. Influences of organic modifier, ionic strength and pH value of buffer on retention behavior were evaluated, and the separation mechanism was also discussed.
文摘Capillary columns are used in both capillary liquid chromatography and capillary electrochromatography. The design for capillary liquid chromatography is discussed in comparison with capillary gas chromatography. The difference of diffusion coefficient in gas and liquid phase is a key role. The study for obtaining a high performance capillary liquid chromatography is discussed. Capillary electrochromatography is recently interesting for its instinct ability to realize a high performance chromatography. Capillary electrochromatography with and without pressurized flow is reviewed briefly. Instrumentation for capillary electrochromatography with pressurized flow is discussed. The port of splitting, and gradient elution of both solution and potential are described. The new findings of both the variation of column resistance and capacity factor according to the value of applied electric voltage are also discussed.
文摘A novel monolithic stationary phase with long alkyl chain ligands was introduced and evaluated in pressurized capillary electrochromatography(p-CEC) by using a mixture of neutral and charged compounds. The capillary monolithic-column was prepared by in situ copolymerization of ethylene dimethacrylate,alkyl alcohol and 2-acrylamido-2-methyl-1-propanesulfonic acid in a quadruple porogenic solvent consisting of 1,4-butanediol/cyclohexanol/docecanol/water. Effects of experimental parameters in p-CEC,such as pressure and electrical field strength,on the separation were investigated. The baseline separation of the components in the mixture was achieved. The monolithic column can be used as an alternative to the conventional capillary column such as the reversed phase ODS.