title: Quantitation of mucus glycoproteins blotted onto nitrocellulose membranes.
abstract: A sensitive assay for mucus glycoproteins (mucins) and fragments thereof is presented. The macromolecules are blotted onto nitrocellulose membranes and visualized using a periodate-Schiff (PAS) reaction and the color yield quantitated with an image analysis system used as a reflectance densitometer. At least 50 ng of the macromolecules was detected. "Whole" mucins and subunits were assayed on 0.2-micron pore size nitrocellulose membranes whereas immobilization of the high-molecular-weight mucin glycopeptides (Mr 300-500,000) required pretreatment of membranes with poly-L-lysine. Binding of the glycopeptides to the polylysine-treated membranes was found to decrease with increasing salt concentration suggesting an electrostatic interaction. The data obtained with this method and a solution PAS assay are in good agreement but the former is more sensitive and can be performed on samples dissolved in chaotropic solvents.
authors.affiliation: Department of Biochemistry & Molecular Biology, University of Manchester, United Kingdom.
authors.forename: D J
authors.initials: DJ
authors.lastname: Thornton
authors.forename: D F
authors.initials: DF
authors.lastname: Holmes
authors.forename: J K
authors.initials: JK
authors.lastname: Sheehan
authors.forename: I
authors.initials: I
authors.lastname: Carlstedt
mesh_terms: D003101:Collodion; D003124:Colorimetry; D004586:Electrophoresis / Q000379:methods; D008567:Membranes, Artificial; D008832:Microchemistry / Q000379:methods; D009077:Mucins / Q000032:analysis*; D010446:Peptide Fragments / Q000032:analysis; D010503:Periodic Acid-Schiff Reaction; D012015:Reference Standards
chemical_list: D008567:Membranes, Artificial; D009077:Mucins; D010446:Peptide Fragments; D003101:Collodion