Molecular weight distribution analysis by ultracentrifugation: adaptation of a new approach for mucins

Carbohydr Polym. 2013 Mar 1;93(1):178-83. doi: 10.1016/j.carbpol.2012.05.018. Epub 2012 May 11.

Abstract

Mucins are the key macromolecular component of mucus, nature's natural lubricant, and one of the most important physical properties is their molecular weight distribution. A new approach for polydisperse polymers was recently published based on sedimentation velocity in the analytical ultracentrifuge and converts a distribution of sedimentation coefficient g(s) vs. s plot into a distribution of molecular weight utilising the power-law or scaling relationship between the sedimentation coefficient and molecular weight, s=κsMw(b) where s is the sedimentation coefficient, Mw is the weight average molecular weight and κs and b are characteristic coefficients related to conformation. We investigate the possibility of using a large database of previously published values of s an M to define κs and b for both aqueous solution and aqueous solution supplemented by 6M guanidine hydrochloride (a solvent which helps to minimise sample degradation). These values are then applied to a study of the molecular weight distributions of preparations of human gastric mucin in the different solvents and at different stages of purification.

MeSH terms

  • Chemical Fractionation / methods*
  • Databases, Factual
  • Gastric Mucins / analysis*
  • Gastric Mucins / chemistry
  • Guanidine / chemistry
  • Humans
  • Molecular Conformation
  • Molecular Weight
  • Solvents / chemistry
  • Thermodynamics
  • Ultracentrifugation / methods*
  • Ultrafiltration
  • Water / chemistry

Substances

  • Gastric Mucins
  • Solvents
  • Water
  • Guanidine