title: Differentiation and detection of PDGF isomers and their receptors by tunable aptamer capillary electrophoresis.
abstract: Tunable aptamer capillary electrophoresis (CE) techniques were developed to enable the separation and detection of platelet derived growth factor (PDGF) isomers and their receptors. Using an aptamer that formed a stable complex with the B chain but not with the A chain of PDGF, we were able to tweak the electrophoretic mobilities of the PDGF isomers for their separation. PDGF-AB bound to a single aptamer molecule was well resolved from PDGF-BB bound to two aptamer molecules. Simultaneous determination of 50 pM of two isomers was accomplished in a single analysis. Furthermore, PDGF-AB was used as a connector to bring receptor alpha and fluorescent aptamer into a single complex molecule. As a result, the formation of a (receptor alpha)-(PDGF-AB)-(fluorescent aptamer) ternary complex enabled the detection of the receptor alpha by tunable aptamer CE. A competitive assay was developed to determine receptor beta, making use of the competition between the receptor beta and fluorescent aptamer in binding to PDGF-BB. Detection limits were 0.5 nM for PDGF receptor alpha and 3 nM for receptor beta. Determination of PDGF isomers and their receptors in diluted serum samples showed no interference from the sample matrix.
authors.affiliation: Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, Faculty of Medicine and Dentistry, 10-102 Clinical Sciences Building, University of Alberta, Edmonton, Alberta, Canada T6G 2G3.
authors.forename: Hongquan
authors.initials: H
authors.lastname: Zhang
authors.forename: Xing-Fang
authors.initials: XF
authors.lastname: Li
authors.forename: X Chris
authors.initials: XC
authors.lastname: Le
mesh_terms: D052157:Aptamers, Nucleotide / Q000737:chemistry / Q000378:metabolism*; D019075:Electrophoresis, Capillary / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D010982:Platelet-Derived Growth Factor / Q000032:analysis* / Q000737:chemistry; D020033:Protein Isoforms / Q000032:analysis / Q000737:chemistry; D017479:Receptors, Platelet-Derived Growth Factor / Q000032:analysis* / Q000097:blood / Q000737:chemistry; D011994:Recombinant Proteins / Q000032:analysis / Q000737:chemistry
chemical_list: D052157:Aptamers, Nucleotide; D005456:Fluorescent Dyes; D010982:Platelet-Derived Growth Factor; D020033:Protein Isoforms; D011994:Recombinant Proteins; D017479:Receptors, Platelet-Derived Growth Factor