Single-Molecule Kinetics of Protein Adsorption on Thin Nylon-6,6 Films

Anal Chem. 2016 Oct 18;88(20):9926-9933. doi: 10.1021/acs.analchem.5b04081. Epub 2016 Sep 29.

Abstract

Understanding and controlling protein adsorption on surfaces is critical to a range of biological and materials applications. Kinetic details that provide the equilibrium and nonequilibrium mechanisms are difficult to acquire. In this work, single-molecule fluorescence microscopy was used to study the adsorption of Alexa 555 labeled α-lactalbumin (α-LA) on two chemically identical but morphologically different polymer surfaces: flat and porous nylon-6,6 thin films. The adsorption kinetics of spatially resolved single molecule α-LA binding to nylon films were quantified by a monolayer adsorption model. The surface morphology of the porous nylon-6,6 films increased the number of adsorption sites but decreased the binding affinity compared to the flat films. Such single-molecule based kinetic studies may be extended to various protein-polymer interactions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adsorption
  • Fluorescence
  • Kinetics
  • Lactalbumin / chemistry*
  • Microscopy, Fluorescence / methods
  • Nylons / chemistry*
  • Porosity
  • Rhodamines / chemistry
  • Sulfonic Acids / chemistry
  • Surface Properties
  • Thermodynamics

Substances

  • Alexa Fluor 555
  • Nylons
  • Rhodamines
  • Sulfonic Acids
  • Lactalbumin