Layer-by-layer polyelectrolyte deposition: a mechanism for forming biocomposite materials.

TitleLayer-by-layer polyelectrolyte deposition: a mechanism for forming biocomposite materials.
Publication TypeJournal Article
Year of Publication2013
AuthorsTan, Y, Yildiz, UHakan, Wei, W, Waite, JH, Miserez, A
Date Published2013 Jun 10
KeywordsBiocompatible Materials, Electrolytes, Solutions, Surface Plasmon Resonance

Complex coacervates prepared from poly(aspartic acid) (polyAsp) and poly-l-histidine (polyHis) were investigated as models of the metastable protein phases used in the formation of biological structures such as squid beak. When mixed, polyHis and polyAsp form coacervates whereas poly-l-glutamic acid (polyGlu) forms precipitates with polyHis. Layer-by-layer (LbL) structures of polyHis-polyAsp on gold substrates were compared with those of precipitate-forming polyHis-polyGlu by monitoring with iSPR and QCM-D. PolyHis-polyAsp LbL was found to be stiffer than polyHis-polyGlu LbL with most water evicted from the structure but with sufficient interfacial water remaining for molecular rearrangement to occur. This thin layer is believed to be fluid and like preformed coacervate films, capable of spreading over both hydrophilic ethylene glycol as well as hydrophobic monolayers. These results suggest that coacervate-forming polyelectrolytes deserve consideration for potential LbL applications and point to LbL as an important process by which biological materials form.

Alternate JournalBiomacromolecules
PubMed ID23600626
PubMed Central IDPMC4104756
Grant ListR01 DE018468 / DE / NIDCR NIH HHS / United States
R01-DE018468 / DE / NIDCR NIH HHS / United States