On-line affinity selection of histidine-containing peptides using a polymeric monolithic support for capillary electrophoresis.
An on-line affinity selection method using a polymeric monolithic support is proposed for the retention of histidine-containing peptides and their subsequent separation by capillary zone electrophoresis (CZE). Monolithic capillary columns were prepared in fused-silica capillaries of 150 mum inner diameter (ID) by ionizing radiation-initiated in situ polymerization and cross-linking of diethylene glycol dimethacrylate and glycidyl methacrylate, and chemically modified with iminodiacetic acid (IDA) and copper ion. Monolithic microextractors were coupled on-line near the inlet of the separation capillary (fused-silica capillary, 75 mum ID x 28 cm from the microextractor to the detector). Model peptide mixtures of histidine-containing and histidine-noncontaining peptides were assessed. Peptides were released from the sorbent by a 5 mM imidazole solution and then separated by CZE with ultraviolet detection. Relative standard deviation values for migration times and corrected peak areas were found to be lower than 5.8 and 10.5%, respectively. IDA-Cu(II) ion modified monolithic microextractors showed a chromatographic behavior and could be reused at least 25 times. The use of monolithic supports proved to be an advantageous alternative to packed particles for the preparation of microextractors.
Vizioli
Nora M
NM
Department of Analytical Chemistry and Physicochemistry, Faculty of Pharmacy and Biochemistry, University of Buenos Aires, Argentina. nvizioli@ffyb.uba.ar
Rusell
Maria Lucía
ML
Carbajal
Maria Laura
ML
Carducci
Clyde N
CN
Grasselli
Mariano
M
D003300:Copper / Q000737:chemistry; D019075:Electrophoresis, Capillary; D006639:Histidine / Q000737:chemistry*; D007098:Imino Acids / Q000737:chemistry; D008689:Methacrylates / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010455:Peptides / Q000032:analysis*; D012822:Silicon Dioxide / Q000737:chemistry
D007098:Imino Acids; D008689:Methacrylates; D010455:Peptides; C508263:poly(diethylene glycol dimethacrylate-co-glycidyl methacrylate); D006639:Histidine; D012822:Silicon Dioxide; D003300:Copper; C008109:iminodiacetic acid