Conditioning of surfaces by macromolecules and its implication for the settlement of zoospores of the green algaUlva linza

Abstract

Conditioning, ie the adsorption of proteins and other macromolecules, is the first process that occurs in the natural environment once a surface is immersed in seawater, but no information is available either regarding the conditioning of surfaces by artificial seawater or whether conditioning affects data obtained from laboratory assays. A range of self-assembled monolayers (SAMs) with different chemical terminations was used to investigate the time-dependent formation of conditioning layers in commercial and self-prepared artificial seawaters. Subsequently, these results were compared with conditioning by solutions in which zoospores of the green alga Ulva linza had been swimming. Spectral ellipsometry and contact angle measurements as well as infrared reflection absorption spectroscopy (IRRAS) were used to reveal the thickness and chemical composition of the conditioning layers. The extent that surface preconditioning affected the settlement of zoospores of U. linza was also investigated. The results showed that in standard spore settlement bioassays (45-60 min), the influence of a molecular conditioning layer is likely to be small, although more substantial effects are possible at longer settlement times.

Surface Sensing and Settlement Strategies of Marine Biofouling Organisms

“…Especially ethylene glycol (EG) x -containing coatings have been used in the biomedical area [21][22][23][24] and have recently been investigated with respect to their marine anti-fouling potential [25][26][27][28][29][30][31][32][33]. However, the degradation of the ethylene-glycol-containing chemistries makes them unsuitable for long-term antifouling applications [34,35]. Other promising approaches involve the use of amphiphilic [26,27,29,36] or zwitterionic chemistries [37][38][39][40].…”

“…FOTS) as the probability to observe patterns indicative of an attractive surface vanish over time [61]. On such hydrophobic surfaces, conditioning films are formed within hours and Thomé et al [35] revealed that the presence of such overlayers decreases the settlement rates of Ulva zoospores by &50 %. Thus it is likely that surface conditioning affects the deceleration and the probability to observe certain motion patterns.…”

“…This, in turn, is affected by the chemical termination of the surface [35,64]. The Callow group established an assay that allows spores to settle within 45 min to surfaces in order to compare the spore accumulation rate on different surfaces and thus to discriminate their non-fouling potential [62].…”

Hydration and Chain Entanglement Determines the Optimum Thickness of Poly(HEMA-co-PEG10MA) Brushes for Effective Resistance to Settlement and Adhesion of Marine Fouling Organisms

“…44,[47][48] Understanding how organic material such as proteins interact and adsorb onto surfaces is important in itself, in order to study correlations with the settlement and adhesion of marine fouling organisms, which frequently use proteinaceous adhesives, or for understanding how macromolecules act to induce gregarious settlement or metamorphosis. 49 Surface resistance to nonspecific protein adsorption is also essential for development of biomaterials and biomedical devices.…”

“…Then, dishes were placed on a rotary shaker at room temperature and shaken for 1 h at 50 rpm to allow attachment of bacteria to the test surfaces. After removing the bacterial suspension, the slides were washed with 10 mL of ASW on a rotary shaker for (1997) 43 and Thome et al (2012). 44 Three replicates of each test surface were placed separately in polystyrene Quadriperm dishes (Greiner Bio-One Ltd.) and 10 mL of spores suspension with OD600nm = 0.15 (1.0 x 10 6 spores ml -1 ) were added.…”