The cellulose tris (4-methylbenzoate) has been synthesised by the catalytic method and was supported at Gas Chrom Q. The absorption capability of cellulose tris (4-methylbenzoate) used as a gas chromatographic station...The cellulose tris (4-methylbenzoate) has been synthesised by the catalytic method and was supported at Gas Chrom Q. The absorption capability of cellulose tris (4-methylbenzoate) used as a gas chromatographic stationary phase was characterized by chromatographic method and the Clausius-Clapeyron equation. However, n-alcohols (C-1-C-8) were successfully separated on the column packed with Gas Chrom Q coated with cellullose tris (4-methylbenzoate).展开更多
Heptakis(2.6-di-O-pentyl-3-O-ally)-β-cyclodextrin as an excellent gas chromatographic stationary phase separating phenol and cresol isomers is described.
A novel stationary phase for weak cation exchange （WCX） chromatography was prepared by ＂grafting from＂ strategy. Surface initiated atom transfer radical polymerization （ATRP） of acrylic acid （AA） was conducted...A novel stationary phase for weak cation exchange （WCX） chromatography was prepared by ＂grafting from＂ strategy. Surface initiated atom transfer radical polymerization （ATRP） of acrylic acid （AA） was conducted in toluene medium, starting from the macromolecule initiators of poly（4-vinylbenzyl chloride-co-divinylbenzene） （PcMs/DvB） beads, The amounts of poly（acrylic acid） grafted chains with different ATRP formulations were calculated based on the elemental analyses. The poly（acrylic acid） grafted beads obtained with different ATRP formula- tions were tried as chromatographic packings in the separation of proteins by ion-exchange chromatography. The effect of the poly（acrylic acid） grafted chain lengths on PCMS/DVB beads for the separation of proteins was investigated in details. Simultaneously, characterization of the column was investigated as ion chromatographic stationary phase for the separation of inorganic cations. The results show that poly（acrylic acid） grafted columns had excellent performance for separation of proteins and inorganic cations. The highest of the dynamic capacity of the column was 35.55 mg/mL. The columns were provided with high column efficiency.展开更多
Molecularly imprinted microspheres (MIMs) were prepared using 4-aminopyridine (4-AP) as template molecule by aqueous microsuspension polymerization. The MIMs were packed into stainless steel column (250×4.6 mm I....Molecularly imprinted microspheres (MIMs) were prepared using 4-aminopyridine (4-AP) as template molecule by aqueous microsuspension polymerization. The MIMs were packed into stainless steel column (250×4.6 mm I.D.) for selective separation of 4-aminopyridine (4-AP) and 2-aminopyridine (2-AP). The influences of pH, kinds and concentration (c) of buffer on capacity factors were investigated in detail. The relationships of capacity factor (k′) with pH and concentration of buffer are quantitatively described firstly. The effects of pH of phosphate and acetate buffer on capacity factors are very different. The relationship between k′ and pH can be described by the following equation: k′=-8.23 + 9.23 pH-0.99 pH 2 (in phosphate buffer) with R 2=0.9775 and k′=6.79-3.76 pH + 0.68 pH 2 (in acetate buffer) with R 2=0.9866. Furthermore, the capacity factors were also greatly affected by the concentration of acetate buffer in mobile phase while non-imprinted molecule is poorly changed. It increases with decreasing the concentration of buffer-especially in low concentration buffer (c acetate<0.02 mol/L, final concentration in mobile phase). The fit curve of log k′ to log c is described by equation: log k′=-0.571-1.256×log c-0.186×(log c) 2 with R 2=0.9979. The ratio of acetate buffer to methanol was investigated and the optimal ratio for separation of 4-AP and 2-AP is below 1∶7.5 (V/V).展开更多
文摘The cellulose tris (4-methylbenzoate) has been synthesised by the catalytic method and was supported at Gas Chrom Q. The absorption capability of cellulose tris (4-methylbenzoate) used as a gas chromatographic stationary phase was characterized by chromatographic method and the Clausius-Clapeyron equation. However, n-alcohols (C-1-C-8) were successfully separated on the column packed with Gas Chrom Q coated with cellullose tris (4-methylbenzoate).
文摘Heptakis(2.6-di-O-pentyl-3-O-ally)-β-cyclodextrin as an excellent gas chromatographic stationary phase separating phenol and cresol isomers is described.
基金Project supported by the Foundation of the Ministery of Science and Technology of China （No. 2009CB626608） and the National Natural Science Foundation of China （No. 201065008）.
文摘A novel stationary phase for weak cation exchange （WCX） chromatography was prepared by ＂grafting from＂ strategy. Surface initiated atom transfer radical polymerization （ATRP） of acrylic acid （AA） was conducted in toluene medium, starting from the macromolecule initiators of poly（4-vinylbenzyl chloride-co-divinylbenzene） （PcMs/DvB） beads, The amounts of poly（acrylic acid） grafted chains with different ATRP formulations were calculated based on the elemental analyses. The poly（acrylic acid） grafted beads obtained with different ATRP formula- tions were tried as chromatographic packings in the separation of proteins by ion-exchange chromatography. The effect of the poly（acrylic acid） grafted chain lengths on PCMS/DVB beads for the separation of proteins was investigated in details. Simultaneously, characterization of the column was investigated as ion chromatographic stationary phase for the separation of inorganic cations. The results show that poly（acrylic acid） grafted columns had excellent performance for separation of proteins and inorganic cations. The highest of the dynamic capacity of the column was 35.55 mg/mL. The columns were provided with high column efficiency.
文摘Molecularly imprinted microspheres (MIMs) were prepared using 4-aminopyridine (4-AP) as template molecule by aqueous microsuspension polymerization. The MIMs were packed into stainless steel column (250×4.6 mm I.D.) for selective separation of 4-aminopyridine (4-AP) and 2-aminopyridine (2-AP). The influences of pH, kinds and concentration (c) of buffer on capacity factors were investigated in detail. The relationships of capacity factor (k′) with pH and concentration of buffer are quantitatively described firstly. The effects of pH of phosphate and acetate buffer on capacity factors are very different. The relationship between k′ and pH can be described by the following equation: k′=-8.23 + 9.23 pH-0.99 pH 2 (in phosphate buffer) with R 2=0.9775 and k′=6.79-3.76 pH + 0.68 pH 2 (in acetate buffer) with R 2=0.9866. Furthermore, the capacity factors were also greatly affected by the concentration of acetate buffer in mobile phase while non-imprinted molecule is poorly changed. It increases with decreasing the concentration of buffer-especially in low concentration buffer (c acetate<0.02 mol/L, final concentration in mobile phase). The fit curve of log k′ to log c is described by equation: log k′=-0.571-1.256×log c-0.186×(log c) 2 with R 2=0.9979. The ratio of acetate buffer to methanol was investigated and the optimal ratio for separation of 4-AP and 2-AP is below 1∶7.5 (V/V).
