Antifouling properties of oligo(lactose)-based self-assembled monolayers

Abstract

The antifouling (AF) properties of oligo(lactose)-based self-assembled monolayers (SAMs), using four different proteins, zoospores of the green alga Ulva linza and cells of the diatom Navicula incerta, were investigated. The SAM-forming alkylthiols, which contained 1, 2 or 3 lactose units, showed significant variation in AF properties, with no differences in wettability. Non-specific adsorption of albumin and pepsin was low on all surfaces. Adsorption of lysozyme and fibrinogen decreased with increasing number of lactose units in the SAM, in agreement with the generally observed phenomenon that thicker hydrated layers provide higher barriers to protein adsorption. Settlement of spores of U. linza followed an opposite trend, being greater on the bulkier, more hydrated SAMs. These SAMs are more ordered for the larger saccharide units, and it is therefore hypothesized that the degree of order, and differences in crystallinity or stiffness between the surfaces, is an important parameter regulating spore settlement on these surfaces.

Keywords:

• marine biofouling
• oligo(lactose)
• self-assembled monolayer
• Ulva linza
• Navicula incerta
• protein resistance

Conflict of interest disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported from the European Community’s Seventh Framework Programme FP7/2007–2013 under Grant Agreement number [23797] (SEACOAT). TE acknowledges financial support from the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University [Faculty Grant SFO-Mat-LiU # 2009-00971]. JF acknowledges ONR (USA) award [N0001-08-1-0010].