Interaction of Proteins with a Planar Poly(acrylic acid) Brush: Analysis by Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D).

Journal Article (Journal Article)

We describe the preparation of a poly(acrylic acid) (PAA) brush, polymerized by atom transfer radical polymerization (ATRP) of tert-butyl acrylate (tBA) and subsequent acid hydrolysis, on the flat gold surfaces of quartz-crystal microbalance (QCM) crystals. The PAA brushes were characterized by Fourier transform infrared (FT-IR) spectroscopy, ellipsometry and water contact angle analysis. The interaction of the PAA brushes with human serum albumin (HSA) was studied for a range of ionic strengths and pH conditions by quartz-crystal microbalance with dissipation monitoring (QCM-D). The quantitative analysis showed a strong adsorption of protein molecules onto the PAA brush. By increasing the ionic strength, we were able to release a fraction of the initially bound HSA molecules. This finding highlights the importance of counterions in the polyelectrolyte-mediated protein adsorption/desorption. A comparison with recent calorimetric studies related to the binding of HSA to polyelectrolytes allowed us to fully analyze the QCM data based on the results of the thermodynamic analysis of the binding process.

Full Text

Duke Authors

Cited Authors

  • Walkowiak, J; Gradzielski, M; Zauscher, S; Ballauff, M

Published Date

  • December 2020

Published In

Volume / Issue

  • 13 / 1

Start / End Page

  • E122 -

PubMed ID

  • 33396873

Pubmed Central ID

  • PMC7795234

Electronic International Standard Serial Number (EISSN)

  • 2073-4360

International Standard Serial Number (ISSN)

  • 2073-4360

Digital Object Identifier (DOI)

  • 10.3390/polym13010122


  • eng