A chiral separation strategy for acidic drugs in capillary electrochromatography using both chlorinated and nonchlorinated polysaccharide‐based selectors

Abstract

A generic chiral separation strategy for the analysis of acidic compounds in CEC is proposed in completion of an earlier defined strategy for nonacidic compounds. The screening step of this strategy uses a 45 mM ammonium formate (pH 2.9)/ACN (35/65, v/v) mobile phase, a temperature of 25°C, and an applied voltage of 15 kV. To update the screening step, eight chiral stationary phases, which all possessed chlorinated and nonchlorinated polysaccharide-based chiral selectors, were evaluated using the earlier defined screening conditions. A combination of the two types of polysaccharide-based chiral phases proved to have the highest cumulative success rate. In the updated screening step, amylose tris(3,5-dimethylphenylcarbamate) (ADH), cellulose tris(4-methylbenzoate) (OJH), cellulose tris(3,5-dichlorophenylcarbamate) (SP5), and cellulose tris(3,5-dimethylphenylcarbamate) (ODRH) were included as selectors and their preferred screening sequence was determined as ADH > OJH > SP5 > ODRH. New optimization steps were also defined for SP5 by investigating the influences of different parameters on the separation outcome using an experimental design approach. After application of the updated strategy, 15 of 17 acidic pharmaceuticals were separated under screening conditions, of which 9 were baseline resolved. When the optimization steps were applied, another three compounds were baseline separated, while the total number of separations was increased by one, which brings the total number of separations to 16 of 17 with 12 baseline separated compounds. This reflects the successful performance of the updated strategy on acidic compounds.

Nano‐amylose‐2,3‐bis(3,5‐dimethylphenylcarbamate)‐silica hybrid sol immobilized on open tubular capillary column for capillary electrochromatography enantioseparation

“…Therefore, the comparisons in chiral separation performance between this nano‐ADMPC hybrid sol coated OT column and the amylose based packed or monolithic columns, other types of OT columns, such as cellulose or nanochitosan based OT column, are listed in Supporting Information Tables 6 and 7, respectively. Seen in Supporting Information Tables 6 and 7, the resolution of this nano‐ADMPC hybrid sol coated OT column compared favorably with the amylose based monolithic columns and nanochitosan‐based OT column , and of course, there is still a certain margin with these amylose based packed columns or cellulose based OT column . Although the peak performances of this OT column are not as good as the well‐established packed column or cellulose based OT column, this OT column exhibits the broad‐spectrum separation ability, and various categories of chiral compounds would be separated employing this OT column, such as amino acids, small molecules, drugs.…”

Determination of 5-nitroimidazole residues in milk by capillary electrochromatography with packed C18 silica beds

“…Several procedures for capillary packing have been described [25] including electrokinetic packing [30,31], packing with supercritical carbon dioxide [32], with centripetal forces [33] or by gravity [34]. However slurry packing with pressure [35][36][37] is the most established methodology because it is simple to implement and it does not require long recipes for startup. The main difficulty of column packing resides in the production of the frits because they have to retain the stationary phase in the capillary when a separation voltage is applied and, at the same time, to allow the mobile phase to penetrate freely through them.…”

Enantiomers separation by capillary electrochromatography using polysaccharide‐based stationary phases

“…The works are organized in two different tables, focusing both on the type of capillary column (packed or monolithic) and on the CS immobilization method (coating or chemically immobilized on silica/zirconia/monolithic material). Therefore, Table 2 presents chiral separations by CEC and OT-CEC using columns packed with polysaccharide derivatives coated on silica gel, whereas Table 3 presents chiral separations by CEC using polysaccharide derivative based CSPs coated or chemically immobilized on zirconia particles or monolithic columns. In this regard, well-known authors in the chromatography field, such as Chankvetadze [31,[34][35][36]40,42,[46][47][48][49][50][51][52][53][54][55][56][57][58]60,61], Blaschke [31,47,49,[51][52][53][54]56], Fanali [33,46,48,57,58,60,61], Mangelings [32,[36][37][38][39][40]…”

“…Vander Heyden and his research group have developed separation strategies based on the large-scale screening of racemic mixtures generally in pharmaceutical products using polysaccharide derivatives based CSPs [36][37][38][39][40][41][42][43][44][45]. In this regard, basic, neutral, and bifunctional pharmaceutical compounds were selected and tested in order to verify the enantiorecognition capabilities of chlorinated [36] and nonchlorinated [37] CSPs, being the firsts superior to the seconds.…”