High performance liquid chromatography with column switching has been developed for the determination of lansoprazole in plasma. The plasma samples were injected onto a pretreatment column packed with LiChromprep RP2 ...High performance liquid chromatography with column switching has been developed for the determination of lansoprazole in plasma. The plasma samples were injected onto a pretreatment column packed with LiChromprep RP2 (25~40 mm) after simple dilution with distilled water. Distilled water was used to wash out protein and other polar components in plasma. After switching, the concentrated lansoprazole was eluted in the backflush mode onto a Shimpack CLC ODS column with methanol 0 2 mol·L 1 ammonium acetate (65:35) as mobile phase. Purge solutions were used for clean up and for regenerating the pretreatment column. The method showed good precision and recovery. The detection limit was 0 005 mg·L -1 plasma. The RSD’s (intra and interday) were less than 2 5% and 5 3% respectively. The method has been successfully used to determine pharmacokinetics of lansoprazole in Chinese volunteers.展开更多
The column wicking technique was applied to estimate the surface free energy of cellulose, the importance of which is to obtain a real effective capillary radius, Reff, initially from the plot of Washburn penetration ...The column wicking technique was applied to estimate the surface free energy of cellulose, the importance of which is to obtain a real effective capillary radius, Reff, initially from the plot of Washburn penetration distance versus time. Since the cellulose sample could not be packed with good reproducibility, therefore, Reff can not be obtained readily from the slope of the plot. A method was developed in this paper by uniting all apparent packing heights with a unique value to deduce a real effective capillary radius. Based on the defined critical packing height related to the critical packing density, the surface free energy and acid-base properties of cellulose Sigma C8002 were estimated.展开更多
The water characteristic curve for aeolian sand in two processes of wetting and drying was obtained by the negative water column technique.The values of fitting parameters were calculated according to Van Genuchten fo...The water characteristic curve for aeolian sand in two processes of wetting and drying was obtained by the negative water column technique.The values of fitting parameters were calculated according to Van Genuchten formula and the parameters that characterized the prosperities of aeolian sand such as the unsaturated infiltration coefficient and specific water capacity were obtained.The results showed that the water characteristic curve for aeolian sand in wetting process had greater hysteresis quality than ...展开更多
文摘High performance liquid chromatography with column switching has been developed for the determination of lansoprazole in plasma. The plasma samples were injected onto a pretreatment column packed with LiChromprep RP2 (25~40 mm) after simple dilution with distilled water. Distilled water was used to wash out protein and other polar components in plasma. After switching, the concentrated lansoprazole was eluted in the backflush mode onto a Shimpack CLC ODS column with methanol 0 2 mol·L 1 ammonium acetate (65:35) as mobile phase. Purge solutions were used for clean up and for regenerating the pretreatment column. The method showed good precision and recovery. The detection limit was 0 005 mg·L -1 plasma. The RSD’s (intra and interday) were less than 2 5% and 5 3% respectively. The method has been successfully used to determine pharmacokinetics of lansoprazole in Chinese volunteers.
基金This work is financially supported by the Chinese Education Ministry and Donghua University of China (No. 2B01).
文摘The column wicking technique was applied to estimate the surface free energy of cellulose, the importance of which is to obtain a real effective capillary radius, Reff, initially from the plot of Washburn penetration distance versus time. Since the cellulose sample could not be packed with good reproducibility, therefore, Reff can not be obtained readily from the slope of the plot. A method was developed in this paper by uniting all apparent packing heights with a unique value to deduce a real effective capillary radius. Based on the defined critical packing height related to the critical packing density, the surface free energy and acid-base properties of cellulose Sigma C8002 were estimated.
基金Supported by Key Project of Science and Technology Research of Ministry of Education(308021)Chang Jiang Scholars Innovation Team of Ministry of Education(IRT0811)Geological Survey Project of China Geological Survey(1212010331302)~~
文摘The water characteristic curve for aeolian sand in two processes of wetting and drying was obtained by the negative water column technique.The values of fitting parameters were calculated according to Van Genuchten formula and the parameters that characterized the prosperities of aeolian sand such as the unsaturated infiltration coefficient and specific water capacity were obtained.The results showed that the water characteristic curve for aeolian sand in wetting process had greater hysteresis quality than ...