UV-C LED-induced cyclobutane pyrimidine dimer formation, lesion repair and mutagenesis in the biofilm-forming diatom, Navicula incerta.

The use of ultraviolet-C (UV-C) irradiation in marine biofouling control is a relatively new and potentially disruptive technology. This study examined effects of UV-C exposure on the biofilm-forming diatom, Navicula incerta. UV-C-induced mutations were identified via Illumina HiSeq. A de novo genome was assembled from control sequences and reads from UV-C-exposed treatments were mapped to this genome, with a quantitative estimate of mutagenesis then derived from the frequency of single nucleotide polymorphisms. UV-C exposure increased cyclobutane pyrimidine dimer (CPD) abundance with a direct correlation between lesion formation and fluency. Cellular repair mechanisms gradually reduced CPDs over time, with the highest UV-C fluence treatments having the fastest repair rates. Mutation abundances were, however, negatively correlated with CPD abundance suggesting that UV-C exposure may influence lesion repair. The threshold fluence for CPD formation exceeding CPD repair was >1.27 J cm-2. Fluences >2.54 J cm-2 were predicted to inhibit repair mechanisms. While UV-C holds considerable promise for marine antifouling, diatoms are just one, albeit an important, component of marine biofouling communities. Determining fluence thresholds for other representative taxa, highlighting the most resistant, would allow UV-C treatments to be specifically tuned to target biofouling organisms, whilst limiting environmental effects and the power requirement.

Effect of Multilayer Termination on Nonspecific Protein Adsorption and Antifouling Activity of Alginate-Based Layer-by-Layer Coatings.

Layer-by-layer (LbL) assembly is a versatile platform for applying coatings and studying the properties of promising compounds for antifouling applications. Here, alginate-based LbL coatings were fabricated by alternating the deposition of alginic acid and chitosan or polyethylenimine to form multilayer coatings. Films were prepared with either odd or even bilayer numbers to investigate if the termination of the LbL coatings affects the physicochemical properties, resistance against the nonspecific adsorption (NSA) of proteins, and antifouling efficacy. The hydrophilic films, which were characterized using spectroscopic ellipsometry, water contact angle goniometry, ATR-FTIR spectroscopy, AFM, XPS, and SPR spectroscopy, revealed high swelling in water and strongly reduced the NSA of proteins compared to the hydrophobic reference. While the choice of the polycation was important for the protein resistance of the LbL coatings, the termination mattered less. The attachment of diatoms and settling of barnacle cypris larvae revealed good antifouling properties that were controlled by the termination and the charge density of the LbL films.

Synthesis of Novel Sulfobetaine Polymers with Differing Dipole Orientations in Their Side Chains, and Their Effects on the Antifouling Properties.

The impact of the orientation of zwitterionic groups, with respect to the polymer backbone, on the antifouling performance of thin hydrogel films made of polyzwitterions is explored. In an extension of the recent discussion about differences in the behavior of polymeric phosphatidylcholines and choline phosphates, a quasi-isomeric set of three poly(sulfobetaine methacrylate)s is designed for this purpose. The design is based on the established monomer 3-[N-2-(methacryloyloxy)ethyl-N,N-dimethyl]ammonio-propane-1-sulfonate and two novel sulfobetaine methacrylates, in which the positions of the cationic and the ionic groups relative to the polymerizable group, and thus also to the polymer backbone, are altered. The effect of the varied segmental dipole orientation on their water solubility, wetting behavior by water, and fouling resistance is compared. As model systems, the adsorption of the model proteins bovine serum albumin (BSA), fibrinogen, and lysozyme onto films of the various polyzwitterion surfaces is studied, as well as the settlement of a diatom (Navicula perminuta) and barnacle cyprids (Balanus improvisus) as representatives of typical marine fouling communities. The results demonstrate the important role of the zwitterionic group's orientation on the polymer behavior and fouling resistance.

Effects of crosslink density in zwitterionic hydrogel coatings on their antifouling performance and susceptibility to silt uptake.

Hydrogel coatings effectively reduce the attachment of proteins and organisms in laboratory assays, in particular when made from zwitterionic monomers. In field experiments with multiple species and non-living material, such coatings suffer from adsorption of particulate matter. In this study, the zwitterionic monomer 3-[N-(2-methacryloyloxyethyl)-N,N-dimethylammonio] propanesulfonate (SPE) was copolymerized with increasing amounts of the photo-crosslinker benzophenon-4-yloxyethyl methacrylate (BPEMA) to systematically alter the density of crosslinks between the polymer chains. The effect of increasing crosslink density on the antifouling (AF) performance of the coatings was investigated in laboratory assays and fields tests. In both cases, the AF performance was improved by increasing the crosslinker content. The coatings reduced protein, diatom, and barnacle accumulation, and showed better resistance to biomass accumulation. The findings underline that the marine AF performance of hydrogel coatings does not only depend on the specific chemical structure of the polymers, but also on their physico-chemical properties such as rigidity and swelling.

Transcriptional characterisation of the Exaiptasia pallida pedal disc.

BACKGROUND: Biological adhesion (bioadhesion), enables organisms to attach to surfaces as well as to a range of other targets. Bioadhesion evolved numerous times independently and is ubiquitous throughout the kingdoms of life. To date, investigations have focussed on various taxa of animals, plants and bacteria, but the fundamental processes underlying bioadhesion and the degree of conservation in different biological systems remain poorly understood. This study had two aims: 1) To characterise tissue-specific gene regulation in the pedal disc of the model cnidarian Exaiptasia pallida, and 2) to elucidate putative genes involved in pedal disc adhesion. RESULTS: Five hundred and forty-seven genes were differentially expressed in the pedal disc compared to the rest of the animal. Four hundred and twenty-seven genes were significantly upregulated and 120 genes were significantly downregulated. Forty-one condensed gene ontology terms and 19 protein superfamily classifications were enriched in the pedal disc. Eight condensed gene ontology terms and 11 protein superfamily classifications were depleted. Enriched superfamilies were consistent with classifications identified previously as important for the bioadhesion of unrelated marine invertebrates. A host of genes involved in regulation of extracellular matrix generation and degradation were identified, as well as others related to development and immunity. Ab initio prediction identified 173 upregulated genes that putatively code for extracellularly secreted proteins. CONCLUSION: The analytical workflow facilitated identification of genes putatively involved in adhesion, immunity, defence and development of the E. pallida pedal disc. When defence, immunity and development-related genes were identified, those remaining corresponded most closely to formation of the extracellular matrix (ECM), implicating ECM in the adhesion of anemones to surfaces. This study therefore provides a valuable high-throughput resource for the bioadhesion community and lays a foundation for further targeted research to elucidate bioadhesion in the Cnidaria.

Antifouling Properties of Dendritic Polyglycerols against Marine Macrofouling Organisms.

Dendritic polyglycerols (PGs) were synthesized and postmodified by grafting of poly(ethylene glycol) (PEG) and polypropylene glycol (PPG) diglycidyl ether groups, and their antifouling and fouling-release properties were tested. Coating characterization by spectroscopic ellipsometry, contact angle goniometry, attenuated total internal reflection-Fourier transform infrared spectroscopy (ATR-FTIR), and atomic force microscopy showed brushlike morphologies with a high degree of microscale roughness and the ability to absorb large amounts of water within seconds. PGs with three different thicknesses were tested in laboratory assays against settlement of larvae of the barnacle Balanus improvisus and against the settlement and removal of zoospores of the alga Ulva linza. Very low coating thicknesses, e.g., 11 nm, reduced the settlement of barnacles, under static conditions, to 2% compared with 55% for an octadecyltrichlorosilane reference surface. In contrast, zoospores of U. linza settled readily but the vast majority were removed by exposure to a shear force of 52 Pa. Both PEG and PPG modification increased the antifouling properties of the PG films, providing a direct comparison of the ultralow fouling properties of all three polymers. Both, the modified and the nonmodified PGs are promising components for incorporation into amphiphilic fouling-resistant coatings.

Microbiome acquisition during larval settlement of the barnacle Semibalanus balanoides.

Barnacles are conspicuous members of rocky intertidal communities and settlement of the final larval stage, the cyprid, is influenced by the presence of biofilms. While modulation of cyprid settlement by biofilms has been studied extensively, the acquisition of a specific microbiome by the settling larva has not. This study investigated settlement in the field of Semibalanus balanoides in two consecutive years when the composition of the benthic bacterial community differed. In both years, settling cyprids adopted a specific sub-set of benthic bacteria that was distinct from the planktonic cyprid and the benthos. This microbiome was consistent, regardless of annual variability in the benthic community structure, and established within hours of settlement. The results imply that a natural process of selection occurs during the critical final transition of S. balanoides to the sessile form. The apparent consistency of this process between years suggests that optimal growth and survival of barnacles could depend upon a complex inter-kingdom relationship, as has been demonstrated in other animal systems.

Correlative assays of barnacle cyprid behaviour for the laboratory evaluation of antifouling coatings: a study of surface energy components.

Laboratory evaluation of antifouling coatings is underpinned by settlement studies with specific fouling organisms. Established methods provide insight into the likelihood of failure of a particular coating system, but can neglect the process of surface selection that often precedes attachment. The present approach for quantifying the exploratory behaviour of barnacle cypris larvae suggested that inspection behaviour can be a rapid and predictive proxy for settlement. Two series of xerogels with comparable total surface energy, but different dispersive and polar components, were evaluated. Settlement assays with three-day-old cyprids of Balanus improvisus demonstrated that while attachment was not linked directly to dispersive free energy, the composition of the xerogel was nevertheless significant. Behavioural analysis provided insight into the mechanism of surface rejection. In the case of a 50:50 PH/TEOS (phenyltriethoxysilane-based) xerogel vs a 50:50 TFP/TEOS (3,3,3-trifluoropropyltrimethoxysilane-based) xerogel, wide-searching behaviour was absent on the former.

Quantitative analysis of the complete larval settlement process confirms Crisp's model of surface selectivity by barnacles.

For barnacle cypris larvae at the point of settlement, selection of an appropriate surface is critical. Since post-settlement relocation is usually impossible, barnacles have evolved finely tuned surface-sensing capabilities to identify suitable substrata, and a temporary adhesion system for extensive surface exploration. The pattern of exploratory behaviour appears complex and may last for several hours, imposing significant barriers to quantitative measurement. Here, we employ a novel tracking system that enables simultaneous analysis of the larval body movement of multiple individuals over their entire planktonic phase. For the first time, to our knowledge, we describe quantitatively the complete settlement process of cyprids as they explore and select surfaces for attachment. We confirm the 'classic' behaviours of wide searching, close searching and inspection that comprise a model originally proposed by Prof. Dennis Crisp FRS. Moreover, a short-term assay of cyprid body movement has identified inspection behaviour as the best indicator of propensity to settle, with more inspection-related movements occurring in conditions that also promote higher settlement. More than half a century after the model was first proposed by Crisp, there exists a precise method for quantifying cyprid settlement behaviour in wide-ranging investigations of barnacle ecology and applied studies of fouling management.

In vivo and in situ synchrotron radiation-based µ-XRF reveals elemental distributions during the early attachment phase of barnacle larvae and juvenile barnacles.

Barnacles are able to establish stable surface contacts and adhere underwater. While the composition of adult barnacle cement has been intensively studied, far less is known about the composition of the cement of the settlement-stage cypris larva. The main challenge in studying the adhesives used by these larvae is the small quantity of material available for analysis, being on the order of nanograms. In this work, we applied, for the first time, synchrotron radiation-based µ-X-ray fluorescence analysis (SR-µ-XRF) for in vivo and in situ analysis of young barnacles and barnacle cyprids. To obtain biologically relevant information relating to the body tissues, adhesives, and shell of the organisms, an in situ sample environment was developed to allow direct microprobe investigation of hydrated specimens without pretreatment of the samples. In 8-day-old juvenile barnacles (Balanus improvisus), the junctions between the six plates forming the shell wall showed elevated concentrations of calcium, potassium, bromine, strontium, and manganese. Confocal measurements allowed elemental characterization of the adhesive interface of recently attached cyprids (Balanus amphitrite), and substantiated the accumulation of bromine both at the point of initial attachment as well as within the cyprid carapace. In situ measurements of the cyprid cement established the presence of bromine, chlorine, iodine, sulfur, copper, iron, zinc, selenium, and nickel for both species. The previously unrecognized presence of bromine, iron, and selenium in the cyprid permanent adhesive will hopefully inspire further biochemical investigations of the function of these substances.

Mini-review: impact and dynamics of surface fouling by solitary and compound ascidians.

Globally, ascidians are a significant contributor to benthic marine fouling communities, but have remained poorly studied in this context. In some cases, such as in shellfish and finfish aquaculture, ascidians are the most problematic of all fouling organisms. The disproportionate impact of ascidian fouling in some specific geographic locations has been related directly to anthropogenic translocation of these organisms around the globe. In the case of ascidians, therefore, the economic issue of biofouling and the ecological ramifications of invasion are inextricably linked. This mini-review briefly discusses the introduction of non-native ascidians to areas where they have subsequently proven to be a significant fouling pest. The elements of ascidian reproductive ecology that support their aggressive fouling character are discussed and the scant information pertaining to their adhesion and adhesives is presented. Finally, strategies for mitigating ascidian fouling are examined. It is suggested that sufficient working knowledge currently exists to support the inclusion of one or more common ascidian species as 'standard' test organisms used for evaluation of novel fouling-resistant surfaces.

Confocal microscopy-based goniometry of barnacle cyprid permanent adhesive.

Biological adhesives are materials of particular interest in the fields of bio-inspired technology and antifouling research. The adhesive of adult barnacles has received much attention over the years; however, the permanent adhesive of the cyprid - the colonisation stage of barnacles - is a material about which very little is presently known. We applied confocal laser-scanning microscopy to the measurement of contact angles between the permanent adhesive of barnacle cyprid larvae and self-assembled monolayers of OH- and CH3-terminated thiols. Measurement of contact angles between actual bioadhesives and surfaces has never previously been achieved and the data may provide insight into the physicochemical properties and mechanism of action of these functional materials. The adhesive is a dual-phase system post-secretion, with the behaviour of the components governed separately by the surface chemistry. The findings imply that the cyprid permanent adhesion process is more complex than previously thought, necessitating broad re-evaluation of the system. Improved understanding will have significant implications for the production of barnacle-resistant coatings as well as development of bio-inspired glues for niche applications.

Studying the Effect of Pre-Polymer Composition and Incorporation of Surface-Modifying Amphiphilic Additives on the Fouling-Release Performance of Amphiphilic Siloxane-Polyurethane Coatings.

Combining amphiphilic fouling-release (FR) coatings with the surface-active nature of amphiphilic additives can improve the antifouling/fouling-release (AF/FR) properties needed to offer broad-spectrum resistance to marine biofoulants. This work is focused on further tuning the amphiphilic character of a previously developed amphiphilic siloxane-polyurethane (SiPU) coating by varying the amount of PDMS and PEG in the base system. Furthermore, surface-modifying amphiphilic additives (SMAAs) were incorporated into these amphiphilic FR SiPU coatings in varying amounts. ATR-FTIR, contact angle and surface energy measurements, and AFM were performed to assess changes in surface composition, wettability, and morphology. AF/FR properties were evaluated using laboratory biological assays involving Cellulophaga lytica, Navicula incerta, Ulva linza, Amphibalanus amphitrite, and Geukensia demissa. The surfaces of these coatings varied significantly upon changes in PDMS and PEG content in the coating matrix, as well as with changes in SMAA incorporation. AF/FR properties were also significantly changed, with formulations containing the highest amounts of SMAA showing very high removal properties compared to other experimental formulations, in some cases better than that of commercial standard FR coatings.

Video observation of surface exploration in cyprids of Balanus amphitrite: the movements of antennular sensory setae.

Video microscopy of cyprids of Balanus amphitrite was used to monitor the action of antennular setae during the exploratory behaviour prior to attachment. In addition, SEM was used to provide a revised description of all antennular setae for that species. The videos describe if a particular seta touches the substratum and the area it can cover during surface exploration. On the fourth segment, the plumose terminal setae A and B are never in contact with the substratum, lack a terminal pore and it is argued that they sense hydrodynamic forces. The aesthetasc-like terminal seta D is likewise held free in the water at all times and it is speculated that it senses dissolved substances, but, since it contains a scolopale rod, it must also have a mechano-receptive function. All remaining antennular setae on the second, third and fourth segments have a terminal pore and it is argued that these are bimodal receptors with both chemo- and mechano-receptive modalities. These setae are also at one time or another in contact with the substratum, except perhaps for the small preaxial seta 2 and terminal seta C. The first seta to contact the surface during a tentative step is radial seta 5, which is longer than all other radial setae. All other setae on the second and third segment are only in contact after a step is completed. When the attachment disc touches the surface (=a step completed) the long and curved postaxial seta 2 (on the second segment) and postaxial seta 3 on the third segment are both flexed to either side of the antennule. This lateral displacement ensures that these two setae can touch large surface areas to either side of the appendage. The four subterminal setae on the fourth segment contact the surface both immediately before and after a step has been completed, and the constant flicking of the segment significantly increases the surface area tested by both these chemoreceptors and by terminal seta E, which can sweep up to 60 µm laterally from the attachment disc. The flicking of the fourth segment may also serve to dilute the boundary layer of chemoreceptors on the fourth segment such as the aesthetasc-like terminal seta D and thus facilitate the detection of new stimuli.

Effects of surface charge and Gibbs surface energy on the settlement behaviour of barnacle cyprids (Balanus amphitrite).

Gibbs surface energy has long been considered to be an important parameter in the design of fouling-resistant surfaces for marine applications. Rigorous testing of the hypothesis that settlement is related to Gibbs surface energy however has never been accomplished, due mainly to practical limitations imposed by the necessary combination of surface engineering and biological evaluation methods. In this article, the effects of surface charge and Gibbs surface energy on the settlement of cyprids of an important fouling barnacle, Balanus amphitrite, were evaluated. Settlement assays were conducted on a range of self-assembled monolayers (SAMs) (CH(3)-, OH-, COOH-, N(CH(3))(3) (+)-, NH(2)-terminated), presented in gold-coated polystyrene well plates, varying in terms of their surface charge and Gibbs surface energy. Contrary to contemporary theory, settlement was not increased by high-energy surfaces, rather the opposite was found to be the case with cyprids settling in greater numbers on a low-energy CH(3)- SAM compared to a high-energy OH- SAM. Settlement was also greater on negatively-charged SAMs, compared to neutral and positively-charged SAMs. These findings are discussed in the context of data drawn from surfaces that varied in multiple characteristics simultaneously, as have been used previously for such experiments. The finding that surface charge, rather than total surface energy, may be responsible for surface selection by cyprids, will have significant implications for the design of future fouling-resistant materials.

In Vitro Oxidative Crosslinking of Recombinant Barnacle Cyprid Cement Gland Proteins.

Barnacle adhesion is a focus for fouling-control technologies as well as the development of bioinspired adhesives, although the mechanisms remain very poorly understood. The barnacle cypris larva is responsible for surface colonisation. Cyprids release cement from paired glands that contain proteins, carbohydrates and lipids, although further compositional details are scant. Several genes coding for cement gland-specific proteins were identified, but only one of these showed database homology. This was a lysyl oxidase-like protein (lcp_LOX). LOX-like enzymes have been previously identified in the proteome of adult barnacle cement secretory tissue. We attempted to produce recombinant LOX in E. coli, in order to identify its role in cyprid cement polymerisation. We also produced two other cement gland proteins (lcp3_36k_3B8 and lcp2_57k_2F5). lcp2_57k_2F5 contained 56 lysine residues and constituted a plausible substrate for LOX. While significant quantities of soluble lcp3_36k_3B8 and lcp2_57k_2F5 were produced in E. coli, production of stably soluble lcp_LOX failed. A commercially sourced human LOX catalysed the crosslinking of lcp2_57k_2F5 into putative dimers and trimers, and this reaction was inhibited by lcp3_36k_3B8. Inhibition of the lcp_LOX:lcp2_57k_2F5 reaction by lcp3_36k_3B8 appeared to be substrate specific, with no inhibitory effect on the oxidation of cadaverine by LOX. The results demonstrate a possible curing mechanism for barnacle cyprid cement and, thus, provide a basis for a more complete understanding of larval adhesion for targeted control of marine biofouling and adhesives for niche applications.

Amphiphilic Nitroxide-Bearing Siloxane-Based Block Copolymer Coatings for Enhanced Marine Fouling Release.

The buildup of organic matter and organisms on surfaces exposed to marine environments, known as biofouling, is a disruptive and costly process affecting maritime operations. Previous research has identified some of the surface characteristics particularly suited to the creation of antifouling and fouling-release surfaces, but there remains room for improvement against both macrofouling and microfouling organisms. Characterization of their adhesives has shown that many rely on oxidative chemistries. In this work, we explore the incorporation of the stable radical 2,2,6,6-tetramethylpipiderin-1-oxyl (TEMPO) as a component in an amphiphilic block copolymer system to act as an inhibitor for marine cements, disrupting adhesion of macrofouling organisms. Using polystyrene-b-poly(dimethylsiloxane-r-vinylmethysiloxane) block copolymers, pendent vinyl groups were functionalized with TEMPO and poly(ethylene glycol) to construct an amphiphilic material with redox active character. The antifouling and fouling-release performance of these materials was investigated through settlement and removal assays of three model fouling organisms and correlated to surface structure and chemistry. Surfaces showed significant antifouling character and fouling-release performance was increased substantially toward barnacles by the incorporation of stable radicals, indicating their potential for marine antifouling applications.

Omics-based molecular analyses of adhesion by aquatic invertebrates.

Many aquatic invertebrates are associated with surfaces, using adhesives to attach to the substratum for locomotion, prey capture, reproduction, building or defence. Their intriguing and sophisticated biological glues have been the focus of study for decades. In all but a couple of specific taxa, however, the precise mechanisms by which the bioadhesives stick to surfaces underwater and (in many cases) harden have proved to be elusive. Since the bulk components are known to be based on proteins in most organisms, the opportunities provided by advancing 'omics technologies have revolutionised bioadhesion research. Time-consuming isolation and analysis of single molecules has been either replaced or augmented by the generation of massive data sets that describe the organism's translated genes and proteins. While these new approaches have provided resources and opportunities that have enabled physiological insights and taxonomic comparisons that were not previously possible, they do not provide the complete picture and continued multi-disciplinarity is essential. This review covers the various ways in which 'omics have contributed to our understanding of adhesion by aquatic invertebrates, with new data to illustrate key points. The associated challenges are highlighted and priorities are suggested for future research.

Attachment strength is a key factor in the selection of surfaces by barnacle cyprids (Balanus amphitrite) during settlement.

This manuscript constitutes the first evidence of the effects of texture on the rate of removal of cyprids from surfaces and the link between settlement preferences and susceptibility to removal by force. Cyprids of Balanus amphitrite settled preferentially on sinusoidal linear textures (1:1 aspect ratio) in the range 0-32 microm, with textures on the scale of the cyprid (512 microm) treated as flat. Polycarbonate was preferred as a substratum to a polydimethylsiloxane (PDMS) elastomer. Textures of 64-256 microm were avoided and the texture of 256 microm in PDMS was the least preferred substratum tested, with no settlement of cyprids. Hydrodynamic removal was inversely correlated to settlement rate on the textures assayed, implying an adaptive response by cyprids to select surface textures to which their attachment was most tenacious. Correlation plots suggest that likelihood of removal by force is not the only factor involved when cyprids elect to settle on a given texture. Choice and no-choice assays delivered different results. This discrepancy is partially ascribed to inherent variability in the choice assay method, but also to the ability of cyprids to compare textures and exercise true choice, biasing settlement towards stimulatory textures in preference to intermediate textures that were settled on in the absence of choice. The identification of a link between settlement preference and likelihood of removal will assist practically in the development of fouling-resistant marine coatings.

Modulation of barnacle (Balanus amphitrite Darwin) cyprid settlement behavior by sulfobetaine and carboxybetaine methacrylate polymer coatings.

Zwitterionic polymers such as poly(sulfobetaine methacrylate) (polySBMA) and poly(carboxybetaine methacrylate) (polyCBMA) have demonstrated impressive fouling-resistance against proteins and mammalian cells. In this paper, the effects of these surface chemistries on the settlement and behavior of an ubiquitous fouling organism, the cypris larva of the barnacle Balanus amphitrite (=Amphibalanus amphitrite), were studied in the laboratory. Conventional settlement assays and behavioral analysis of cyprids using Noldus Ethovision 3.1 demonstrated significant differences in settlement and behavior on different surfaces. Cyprids did not settle on the polySBMA or polyCBMA surfaces over the course of the assay, whereas settlement on glass occurred within expected limits. Individual components of cyprid behavior were shown to differ significantly between glass, polySBMA and polyCBMA. Cyprids also responded differently to the two zwitterionic surfaces. On polySBMA, cyprids were unwilling or unable to settle, whereas on polyCBMA cyprids did not attempt exploration and left the surface quickly. In neither case was toxicity observed. It is concluded that a zwitterionic approach to fouling-resistant surface development has considerable potential in marine applications.