title: Capillary electrophoretic analysis of meningococcal polysaccharide-diphtheria toxoid conjugate vaccines.
abstract: Protein-polysaccharide conjugate vaccines are large, complex molecules that present challenges in terms of characterization. Free solution capillary electrophoresis using alkaline (pH 9-10) borate or glycine/NaOH buffers permitted electrophoresis of diphtheria toxoid (Dt) or meningococcal polysaccharide-Dt conjugates as well-formed, relatively broad peaks. Resolution was observed between the conjugate and the Dt peaks for some serotypes; however, overlap between Dt and one or more conjugate peaks was observed with both buffers. Inclusion of SDS in the separation buffer at a level above the critical micelle concentration allowed separation of Dt and Dt-conjugates of meningococcal serotypes A, C, Y and W135. Using borate/SDS, a linear relationship between peak area and Dt concentration was observed between approximately 2 mg/ml and 20 microg/ml. A linear relationship between Dt peak area and injection times from 10 to 50 seconds was also observed. Capillary electrophoresis may therefore be a useful method for quantifying free protein level in meningococcal-Dt conjugate vaccines.
authors.affiliation: Aventis Pasteur, Swiftwater, PA 18370-0187, USA.
authors.forename: D H
authors.initials: DH
authors.lastname: Lamb
authors.forename: L
authors.initials: L
authors.lastname: Summa
authors.forename: Q P
authors.initials: QP
authors.lastname: Lei
mesh_terms: D002352:Carrier Proteins / Q000737:chemistry / Q000302:isolation & purification; D004168:Diphtheria Toxoid / Q000737:chemistry* / Q000302:isolation & purification; D019075:Electrophoresis, Capillary; D022401:Meningococcal Vaccines / Q000737:chemistry* / Q000302:isolation & purification; D011135:Polysaccharides, Bacterial / Q000737:chemistry* / Q000302:isolation & purification; D013056:Spectrophotometry, Ultraviolet; D018074:Vaccines, Conjugate / Q000737:chemistry*
chemical_list: D002352:Carrier Proteins; D004168:Diphtheria Toxoid; D022401:Meningococcal Vaccines; D011135:Polysaccharides, Bacterial; D018074:Vaccines, Conjugate