Model Study And Alkaloid Detection Based On Moving Reaction Boundary

Moving reaction boundary (MRB) played an important role in CE and has many advantages. This paper studied Moving affinity interaction Boundary(MAIB) which developed MRB in the first part and achieved stacking of sophoridine based on MRB in the second part.Relied on the exclusive affinity interaction between Histidine (His) and metal ion such as Ni, the first part of the research innovates an on-line non-immobilized focusing method for selective determination of His in 20 basic amino acids and urine samples. The experimental conditions optimized are: 208 nm detection wavelength, 53 cm capillary length (44 cm effective length), 12 kv voltage, 50 mM pH 6.0 Na2HPO4-NaH2PO4 buffer with 1 mM NaCl, 2 mM Ni(â…¡) in the anodic cell. Under the optimum conditions, LOD of His would reach 36 ng/ml, LOQ of His was 120 ng/ml, the focusing fold was above 48 in contrast to that in normal capillary zone electrophoresis. Moreover, the relevant correlation coefficient could reach 99.0% in linearity test. Through this novel and feasible method, the procedure could achieve selective sensitive determination of His in 20 amino acids sample matrix. In addition, urine as a positive sample of His was analyzed by using the developed method. The results indicated the potential applicability of this developed method for high selective determination of His in complex sample matrix.The second part of the experimental research was the application of MRB in alkaloid stacking detection. An improvement was achieved by introducing separation and stacking sections compared with normal capillary electrophoresis. The optimized experimental conditions were: 100 mM HCOONa (pH 10.80 adjusted by ammonia) as sample phase, 40 mM HCOOH-HCOONa (pH 2.60) as stacking section, 40 mM HCOOH-HCOONa (pH 2.60) as separation section, 214 nm wavelength, with the 2 min injection of sample, the limit of detection (LOD) for SRI is 0.492 ug/ml, and the limit of quantitation (LOQ) is 1.640 ug/ml. After extraction from rat blood complex by chloroform, the linear response in blood complex was obtained for SRI concentration ranging from 1 ug/ml to 40 ug/ml with the relevant correlation coefficient of 99.2%. The concentration fold could reach over 12. In the reproducibility of the method experiment, the inter-day relative standard deviation (RSD) values, obtained in five different days, of 20 ug/ml and 40 ug/ml SRI were 3.83% and 0.88%, and the inter-day RSD values of them were 2.05% and 2.96%, respectively, which showed good precision of the method.The above two experimental parts in this research unveiled, the MRB method was well developed in affinity reation, i.e. MAIB, in which the very simple experimental system could well achieve selective focusing of His in amino acids mixture and His-positive complex urine by affinity capillary electrophoresis; meanwhile, stacking of alkaloid was a successful application and further prove of MRB. The research of MAIB was promising in proteomics and alkaloid stacking held profound meanings in pharmacy.