Using cation-selective exhaustive injection and sweeping micellar electrokinetic chromatography to determine selective serotonin reuptake inhibitors

On-Column Preconcentration of Anti-Inflammatory Drugs in River Water by Anion-Selective Exhaustive Injection-Sweeping-MEKC

“…Concentrations higher than 50 mM did not increase the peak height and a peak broadening was observed. This may be due to the increase of the retention factors of the analytes, and the difference between the electric field strength in sample zone and that in buffer zone with the increase of SDS concentration, which will improve the stacking efficiency [24]. Therefore, considering the separation efficiency and the sensitivity enhancement factor, we concluded that 50 mM was the optimal concentration for SDS.…”

“…Previous studies had demonstrated that the stacking efficiency and the peak shapes markedly improved when a HCB zone was injected before the Milli-Q water plug [18,22,24,28], as a result of the different electric field strengths between the Milli-Q water plug and the HCB plug. The HCB was used to form a wall, thereby reducing the anionic analytes' velocities and resulting in the anions stacking in a narrow zone.…”

“…In the ASEI-sweeping-MEKC methodology, the concentration of micelles is assumed to be an essential variable as they exert a deep effect on both separation and sweeping concentration [24,26,27]. In an attempt to enhance the enriching sensitivity, the influence of the concentration of the SDS was studied in the range of 25-60 mM.…”

“…The properties of the sample matrix, including its acidity and conductivity, have significant impact on the sensitivity of ASEI-sweeping [23,24]. The influence of sample pH on NSAIDs stacking was first examined, since the amount of analytes that is introduced during the ASEI step depends on the dissociation degree of analytes in the sample matrix [20].…”

Simultaneous Determination of Antidepressants by Non-aqueous or Quasi-non-aqueous Capillary Electrophoresis

“…[12][13][14][15][16][17][18] Non-aqueous capillary electrophoresis (NACE) has emerged as an alternative to obtain the high-resolution separations of hydrophobic drugs. [19][20][21][22] The NACE method uses an organic solvent instead of an aqueous buffer as the background electrolyte, which is useful for antidepressants.…”