A new biomimetic bulk acoustic wave sensor based on molecularly imprinted microspheres (MUM) technique was described. The sensing materials were synthesized by precipitation polymerization. By using the Scatchard anal...A new biomimetic bulk acoustic wave sensor based on molecularly imprinted microspheres (MUM) technique was described. The sensing materials were synthesized by precipitation polymerization. By using the Scatchard analysis, the equilibrium dissociation constant K-D and the apparent maximum number Q(max) of the binding sites were calculated to be 3.70 mmol (.) L-1 and 9.11 mumol (.) g(-1), respectively. The sensor exhibited a sensitive response to the template compound (dipyridamole) in liquid phase with a detection Unfit of 2 x 10(-9) mol (.) L-1. The recoveries of the sensor were 95.1%-105.4%. Studies presented in this paper show that the stability of this sensor is excellent. The sensor has been applied successfully to the determination of dipyridamole in human urine.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A new biomimetic bulk acoustic wave sensor based on molecularly imprinted microspheres (MUM) technique was described. The sensing materials were synthesized by precipitation polymerization. By using the Scatchard analysis, the equilibrium dissociation constant K-D and the apparent maximum number Q(max) of the binding sites were calculated to be 3.70 mmol (.) L-1 and 9.11 mumol (.) g(-1), respectively. The sensor exhibited a sensitive response to the template compound (dipyridamole) in liquid phase with a detection Unfit of 2 x 10(-9) mol (.) L-1. The recoveries of the sensor were 95.1%-105.4%. Studies presented in this paper show that the stability of this sensor is excellent. The sensor has been applied successfully to the determination of dipyridamole in human urine.
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).