title: The physicochemical characterisation of pepsin degraded pig gastric mucin.
abstract: Mucins are the main macromolecular components of the mucus secretions that cover the oral cavity, gastrointestinal and urogenital tracts of animals. The properties of the mucus secretions are therefore directly correlated with the physicochemical properties of mucin glycoproteins. In this study, mucins were obtained from pig gastric mucous after digestion with pepsin at 37°C for 4h, these mucins were characterised in terms of compositional and hydrodynamic properties. Compositional analysis showed that this mucin contains protein (15%), carbohydrates (55%) of which the constituents are: fucose (4%), galactose (9%), glucosamine (55%), glucosamine (33%) and sialic acid (2%). The latter component gives the mucin polymer a pH-dependant negative charge, with a ζ-potential of -3mV at pH 1.2 up to -11mV at pH 7.4. The weight average molar mass was ∼1×10(6)g/mol and intrinsic viscosity was ∼0.42dL/g although there was a small pH dependency due to the polyelectrolyte behavior of the polymer. The measurements of viscosity versus shear rate showed shear thinning behavior and the critical overlap concentration was determined to be 10-11% w/v indicating a compact structure. Knowledge of these properties is fundamental to the understanding interactions of mucins, with for example, novel drug delivery systems.
authors.affiliation: Department of Chemical Sciences, School of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH, UK; Department of Pharmacy, School of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH, UK.
authors.forename: Atiga
authors.initials: A
authors.lastname: Abodinar
authors.affiliation: Biofac A/S, Englandsvej 350-356 DK-2770 Kastrup, Denmark.
authors.forename: Kristoffer
authors.initials: K
authors.lastname: Tømmeraas
authors.affiliation: Biofac A/S, Englandsvej 350-356 DK-2770 Kastrup, Denmark.
authors.forename: Elena
authors.initials: E
authors.lastname: Ronander
authors.affiliation: Department of Pharmacy, School of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH, UK.
authors.forename: Alan M
authors.initials: AM
authors.lastname: Smith
authors.affiliation: Department of Chemical Sciences, School of Applied Sciences, University of Huddersfield, Huddersfield HD1 3DH, UK. Electronic address: g.morris@hud.ac.uk.
authors.forename: Gordon A
authors.initials: GA
authors.lastname: Morris
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D004337:Drug Carriers / Q000737:chemistry / Q000378:metabolism; D005752:Gastric Mucins / Q000737:chemistry* / Q000378:metabolism*; D057446:Hydrodynamics; D055595:Mechanical Phenomena; D010434:Pepsin A / Q000378:metabolism*; D059748:Proteolysis; D012212:Rheology; D013552:Swine
chemical_list: D004337:Drug Carriers; D005752:Gastric Mucins; D010434:Pepsin A
keywords: Compact conformation; Pepsin degraded mucin; Physicochemical properties