Separation of basic drug enantiomers by capillary electrophoresis using chicken α₁‐acid glycoprotein: Insight into chiral recognition mechanism

Abstract

Recombinant chicken alpha(1)-acid glycoprotein (alpha(1)-AGP) was prepared by the Escherichia coli expression system and completely deglycosylated alpha(1)-AGP (cd-alpha(1)-AGP) was obtained by treatments of native alpha(1)-AGP with a mixture of endoglycosidase and N-glycosidase. The average molecular masses of chicken alpha(1)-AGP, cd-alpha(1)-AGP and recombinant alpha(1)-AGP were estimated to be about 29 200, 21 700 and 20 700, respectively, by matrix-assisted laser desorption-time of flight-mass spectrometry. We compared the chiral recognition ability of chicken alpha(1)-AGP, cd-alpha(1)-AGP and recombinant alpha(1)-AGP using them as chiral selectors in capillary electrophoresis. The chicken alpha(1)-AGP showed higher resolution for eperisone, pindolol and tolperisone than cd-alpha(1)-AGP or recombinant alpha(1)-AGP. Recombinant alpha(1)-AGP still showed chiral recognition for three basic drugs tested. By addition of propranolol as a competitor in the separation solution in CE, no enantioseparations of three basic drugs were observed with chicken alpha(1)-AGP, cd-alpha(1)-AGP or recombinant alpha(1)-AGP. These results reveal that the protein domain of the chicken alpha(1)-AGP is responsible for the chiral recognition ability, and that the chiral recognition site(s) for basic drugs exists on the protein domain.

Recent applications and chiral separation development based on stationary phases in open tubular capillary electrochromatography (2019–2022)

“…Because bacteria have intrinsic chirality, adhering non-pathogenic Escherichia coli ( E. coli ) DH5α to the inner wall of the OT column prepared by adhering to positively charged polyethyleneimine can baseline separate enantiolate fluoroquinolone isomers and ofloxacin, as well as partially separate lomefloxacin enantiomers [ 104 ]. It is even possible to use the E. coli expression system to produce recombinant chicken α1-acid glycoprotein (α1-AGP) and modify it in the column after pretreatment [ 105 ]. This column has chiral recognition ability and can separate three basic drugs.…”

Chiral Separations by Capillary Electrophoresis

“…Matsannga et al [107] synthesized and characterized three types of glycoprotein by mass spectrometry: recombinant chicken α 1 -glycoprotein, completely deglycosylated α 1-glycoprotein, and native chicken α 1 -glycoprotein. Then they were used as chiral selectors in CE for the separation of eperisone, pindolol, and tolperisone.…”

New mathematic model for predicting chiral separation using molecular docking: Mechanism of chiral recognition of triadimenol analogues

“…The chiral selector can be directly added to the running buffer to provide chiral environment and a pair of enantiomers be separated due to the discrepancy of the interactions between chiral selectors and enantiomers. Macrocyclic antibiotics [1], polysaccharides [2], chondroitin sulfate C [3], colominic acid [4], chicken alpha1-acid glycoprotein [5,6], vancomycin and balhimycin [7], etc. were already used as chiral selectors.…”