Zein adsorption to hydrophilic and hydrophopic surfaces investigates by surface plasmon resonance

Qin Wang, Jin Feng Wang, Phillip H. Geil, Graciela Wild Padua

Research output: Contribution to journalArticlepeer-review


Zein, the prolamine of corn, has been investigated for its potential as an industrial biopolymer. In previous research, zein was plasticized with oleic acid and formed into sheets/films. Physical properties of films were affected by film structure and controlled in turn by zein-oleic acid interactions. The nature of such interactions is not well understood. Thus, protein-fatty acid interactions were investigated in this work by the use of surface plasmon resonance (SPR). Zein adsorption from 75% aqueous 2-propanol solutions, 0.05% to 0.5% w/v, onto hydrophilic and hydrophobic self-assembled monolayers (SAMs) formed by 11-mercaptoundecanoic acid and 1-octanethiol, respectively, was monitored by high time resolution SPR. Initial adsorption rate and ultimate surface coverage increased with bulk protein concentration for both surfaces. The initial slope of plotted adsorption isotherms was higher on 11-mercaptoundecanoic acid than on 1-octanethiol, indicating higher zein affinity for hydrophilic SAMs. Also, maximum adsorption values were higher for zein on hydrophilic than on hydrophobic SAMs. Flushing off loosely bound zein in the SPR cell allowed estimation of apparent monolayer values. Differences in monolayer values for hydrophobic and hydrophilic surfaces were explained in terms of zein adsorption footprint.

Original languageEnglish (US)
Pages (from-to)1356-1361
Number of pages6
Issue number4
StatePublished - Jul 2004

ASJC Scopus subject areas

  • Bioengineering
  • Biomaterials
  • Polymers and Plastics
  • Materials Chemistry


Dive into the research topics of 'Zein adsorption to hydrophilic and hydrophopic surfaces investigates by surface plasmon resonance'. Together they form a unique fingerprint.

Cite this