The entropy increase (EI) and the entropy increase per unit time (EIPUT) of the solute zone are chosen as new criteria of separation efficiency in chromatography and electrophoresis. It is verified by grand canonical ...The entropy increase (EI) and the entropy increase per unit time (EIPUT) of the solute zone are chosen as new criteria of separation efficiency in chromatography and electrophoresis. It is verified by grand canonical ensemble (GCE) that the kinetic energy distribution of the solute is a common characteristic of the entropy and the distribution of solute zones.Under the assumptions. EI of the solute system is directly proportional to the logarithm of the difference between one and one half of the substantial separation ratio. the ratio of moles of a sparated solute to its total moles. and EIPUT is direchy proportional to corrected separation rate of separation system. EI or EIPUT is a important bridge between separation efficiency of chromatography or electrophoresis and operating parameters, especially. when nonequilibriumthermodynamics(NET) would be adopted.展开更多
Development of effective chromatographic or electrophoretic separation involves judicious deciding of selection of optimal experimental conditions that can provide an adequate resolution at a reasonable run time for t...Development of effective chromatographic or electrophoretic separation involves judicious deciding of selection of optimal experimental conditions that can provide an adequate resolution at a reasonable run time for the separation of interested components. Box-Behnken factorial design was effectively applied for the separation optimization of eight structurally related sulfonamides using capillary zone electrophorosis and reverse high performance liquid chromatography. Optimum values for volume ratio of THF to H2O in eluent, column temperature and flow rate of eluent are found as 12 to 88, 35℃ and 1.0 mL/min, respectively. Box-Behnken modified optimization model is extended to separation by capillary electrophoresis (CE). While using CE, a satisfactory separation is achieved with a minimum resolution larger than 1.0 for a separation time less than 10 min.展开更多
In order to determine the optimal mode of capillary electrophoresis for the impurity control of β-lactam antibiotics, different modes and various electrophoresis conditions for the separation of impurities were compa...In order to determine the optimal mode of capillary electrophoresis for the impurity control of β-lactam antibiotics, different modes and various electrophoresis conditions for the separation of impurities were compared.The results showed that micellar electrokinetic capillary chromatography（MEKC） was the optimal separation mode for the impurity profiling of β-lactam antibiotics.In MEKC,not only the common R and S isomers,Δ-2 andΔ-3 isomers,and Z and E isomers,but also the impurities of β-lactam antibiotics could be well separated compared with the capillary zone electrophoresis.Therefore,MECK is the first choice for the separation of impurities of β-lactam antibiotics with capillary electrophoresis（CE）.The optimal separation could be achieved in MEKC by optimizing the pH and the concentrations of buffered saline,micelles and organic solvent（methanol） in running buffer.展开更多
文摘The entropy increase (EI) and the entropy increase per unit time (EIPUT) of the solute zone are chosen as new criteria of separation efficiency in chromatography and electrophoresis. It is verified by grand canonical ensemble (GCE) that the kinetic energy distribution of the solute is a common characteristic of the entropy and the distribution of solute zones.Under the assumptions. EI of the solute system is directly proportional to the logarithm of the difference between one and one half of the substantial separation ratio. the ratio of moles of a sparated solute to its total moles. and EIPUT is direchy proportional to corrected separation rate of separation system. EI or EIPUT is a important bridge between separation efficiency of chromatography or electrophoresis and operating parameters, especially. when nonequilibriumthermodynamics(NET) would be adopted.
基金Project(20235010) support by the NSFC-KOSEF Scientific Cooperation ProgramProject supported by the Program for New Century Talents of University in Henan ProvinceProgram for Backbone Teacher in Henan Province, China
文摘Development of effective chromatographic or electrophoretic separation involves judicious deciding of selection of optimal experimental conditions that can provide an adequate resolution at a reasonable run time for the separation of interested components. Box-Behnken factorial design was effectively applied for the separation optimization of eight structurally related sulfonamides using capillary zone electrophorosis and reverse high performance liquid chromatography. Optimum values for volume ratio of THF to H2O in eluent, column temperature and flow rate of eluent are found as 12 to 88, 35℃ and 1.0 mL/min, respectively. Box-Behnken modified optimization model is extended to separation by capillary electrophoresis (CE). While using CE, a satisfactory separation is achieved with a minimum resolution larger than 1.0 for a separation time less than 10 min.
基金National Key New Drug R&D Program Foundation of China(Grant No.2009ZX09313-027)
文摘In order to determine the optimal mode of capillary electrophoresis for the impurity control of β-lactam antibiotics, different modes and various electrophoresis conditions for the separation of impurities were compared.The results showed that micellar electrokinetic capillary chromatography（MEKC） was the optimal separation mode for the impurity profiling of β-lactam antibiotics.In MEKC,not only the common R and S isomers,Δ-2 andΔ-3 isomers,and Z and E isomers,but also the impurities of β-lactam antibiotics could be well separated compared with the capillary zone electrophoresis.Therefore,MECK is the first choice for the separation of impurities of β-lactam antibiotics with capillary electrophoresis（CE）.The optimal separation could be achieved in MEKC by optimizing the pH and the concentrations of buffered saline,micelles and organic solvent（methanol） in running buffer.
