Les polymères biomimétiques incorporant des groupes zwitterioniques mimant la phosphatidylcholine, comme par exemple la phosphobétaïne, la sulfobétaïne ou encore la carboxybétaïne, ont reçu une attention grandissante pour une utilisation dans la prochaine génération de matériaux en contact avec le sang, grâce à leur excellentes propriétés anti-bioadhésives. Le poly(methacrylate de sulfobétaïne) (polySBMA), avec un squelette methacrylate et un analogue de la taurine bétaïne (CH2CH2N+(CH3)2CH2CH2CH2SO3-) comme groupe pendant, est de loin le polymère le plus étudié en raison de sa relative facilité de préparation. Il est maintenant admis que les brosses polymères recouvrant une surface de groupes zwitterioniques permettent l'obtention d'une surface résistance à l'adsorption de biocomposants, permettant d'envisager une application potentielle pour des matériaux mis en contact du sang, comme les implants par exemple. Dans cette thèse, la nouvelle fonctionnalisation de copolymères dérivés du sulfobétaïne et leurs potentielles applications sont développées et étudiées.Dans une première partie, des copolymères diblocs « schizophréniques » contenant des blocs nonioniques et zwittérioniques ont été préparés pour différentes masses molaires via la polymérisation radicalaire contrôlée (ATRP : atom-transfer radical polymerization). Dans ce travail nous présentons une étude systématique de la relation entre la conformation des chaînes copolymères en solution et leur impact sur l'hémocompatibilité dans une solution de sang humain. Le comportement « schizophrénique » de copolymères PNIPAAm-b-PSBMA a été observé par RMN 1H, diffusion dynamique de la lumière et turbidité, démontrant ainsi une double transition morphologique avec à la fois une LCST (lower critical solution temperature) et une UCST (upper critical solution temperature) en solution aqueuse. En dessous de l'UCST du bloc PSBMA, des micelles sont obtenues avec un cœur insoluble de PSBMA entouré d'une écorce soluble de PNIPAAm alors que la structure inverse est observée au-dessus de la LCST du bloc PNIPAAm. Entre l'UCST et la LCST, des unimères parfaitement solubles ont été détectés. La taille hydrodynamique des copolymères et des homopolymères correspondants a également permise de corréler directement la morphologie micellaire avec la compatibilité avec du sang humain. L'adsorption isolée de fibrinogènes humains sur le copolymère à bloc a été étudiée par DLS pour déterminer la stabilité de la résistance à la bio-adhésion d'une suspension de copolymères. Le PNIPAAm-b-PSBMA a démontré une activité anti-coagulante et anti-hémolytique extrêmement élevées sur une large gamme de température allant de 4 à 40°C. La non-dépendance de la biocompatibilité à la température, associée au comportement schizophrénique en solution aqueuse, nous a amené à réfléchir à d'éventuelles applications.Dans la seconde partie de ce manuscrit, des copolymères diblocs « intelligents » contenant des blocs ioniques et zwittérioniques ont été préparés par polymérisation radicalaire contrôlée de type RAFT (reversible the addition-fragmentation chain transfer). Dans ce travail, nous présentons une étude systématique sur la formation d'un nouveau vecteur d'ADN à partir d'un coeur polyplexe ADN/ poly(dimethylaminoethyl methacrylate) (PDMAEMA), recouvert, via des interactions électrostatiques, de copolymères poly(acide acrylique)-block-poly(méthacrylate de sulfobétaïne) (PAA-b-PSBMA). Son impact sur l'hémocompatibilité ainsi que sur l'efficacité de la transfection de gènes ont été vérifiés, en prenant comme référence des polyplexes formés à partir de polyethyleneimine (Pei). La capacité d'interaction des plasmides ADN avec le Pei, PDMAEMA, et PAA-b-PSBMA a été évaluée par « ethidium bromide displacement assays » et « agarose gel retardation assays » en fixant le rapport en atomes d'azote de polymère par atomes de phosphore des nucléotides (rapport N/P) ainsi que le pH de la solution. La mesure du temps de coagulati / Biomimetic polymers containing zwitterionic structures poly(sulfobetaine methacrylate) (polySBMA) has become the most widely studied zwitterionic polymer due to its easy of synthetic preparation. It is now recognized that grafted dense polymer brushes, composed of zwitterionic polySBMA, formed an effective and stable nonfouling surface, potentially enabling the practical use in human blood-contacting devices and implants. In this dissertation, the new functionalization of zwitterionic sulfobetaine-based copolymers and their potential biomedical applications was developed and investigated. In the first part of the dissertation, “schizophrenic” diblock copolymers containing nonionic and zwitterionic blocks were prepared with well-controlled molecular weights via the atom-transfer radical polymerization (ATRP). In this work, we demonstrate a systematic study of how morphological changes of poly(N-isopropylacrylamide)-block-poly(sulfobetaine methacrylate) (PNIPAAm-b- PSBMA) copolymers affect hemocompatibility in the human blood solution. The “schizophrenic” behavior of PNIPAAm-b-PSBMA was observed by 1H nuclear magnetic resonance (1H NMR), dynamic light scattering (DLS), and turbidity measurement with double morphological transition, exhibiting both lower critical solution temperature (LCST) and upper critical solution temperature (UCST) in aqueous solution. Human fibrinogen adsorption onto the PNIPAAm-b-PSBMA copolymers from single-protein solutions was measured by DLS to determine the nonfouling stability of copolymer suspension. The new nonfouling nature of PNIPAAm-b-PSBMA copolymers was demonstrated to show an extremely high anticoagulant activity and antihemolytic activity in human blood over a wide range of explored temperatures from 4 ºC to 40 ºC and suggests their potential in blood-contacting applications.In the second part of the dissertation, “intelligent” diblock copolymers containing ionic and zwitterionic blocks were prepared with well-controlled molecular weights via reversible the addition-fragmentation chain transfer (RAFT) polymerization. In this work, we demonstrate a systematic study of how zwitterionic shielding on a new self-assembled cargo of plasmid DNA/poly(dimethylaminoethyl methacrylate) (PDMAEMA) polyplexes conjugated with poly(acrylic acid)-block-poly(sulfobetaine methacrylate) (PAA-b-PSBMA) copolymers affect hemocompatibility in human blood solution and gene transfection onto target cells. The carrier stability, cell toxicity, hemocompatibility, and gene transfection efficiency of DNA/ PDMAEMA/PAA-b-PSBMA polyplexes was investigated as compared with DNA/polyethyleneimine (PEI)/PAA-b-PSBMA. Hemocompatibility of the prepared polyplexes was evaluated by the anticoagulant activity of the blood coagulant determined by testing the plasma-clotting time and the antihemolytic activity in human blood by measuring red blood-cell hemolysis. The pH-dependent gene transfection of DNA/ PDMAEMA/PAA-b-PSBMA polyplexes, along with their stimuli-responsive behavior, suggests their potential in blood-contacting gene delivery applications.In the final part of the dissertation, ionic/zwitterionic PAA-b-PSBMA diblock copolymer was extended to prepare anti-fouling poly(ether imide) membranes with well-controlled nano-pore structures and water flux via layer-by-layer self-assembled coating process. The surface charge property of the prepared membrane can be regulated by PEI/PAA ratios. Low protein-fouling membrane surfaces from BSA and fibrinogen solution with respect to uncoated membrane surfaces are achieved with optimized block ratio of PAA and PSBMA. Thus, positively charged membranes, coated with zwitterionic copolymers containing anionic groups via charge-driven, are ideal for highly resisting protein adsorption if the membrane surface density of the zwitterionic groups is controlled to a high-level densities.

Thesis (M.S.)--Auburn University, 2008. / Abstract. Includes bibliographical references.

Memoria para obtener el título de Ingeniero Civil Química / Las estructuras inmersas en el agua de mar son afectadas por un fenómeno común llamado biofouling, donde diferentes organismos se adhieren a la superficie. Este fenómeno produce grandes problemas en la industria marina, generando la necesidad de nuevos materiales con propiedades antifouling. Para ello, los polímeros biocidas son de interés debido a su versatilidad. En estudios recientes se ha demostrado que polímeros con nanopartículas de cobre permiten eliminar bacterias propias de las etapas tempranas del biofouling, sin embargo, la incorporación de nanopartículas es costosa. El objetivo de este Trabajo es estudiar una nueva metodología, sencilla y económica para la fabricación de compuestos de polipropileno con cobre como agente antifouling. Esta metodología consiste en la síntesis in-situ de partículas de cobre en la matriz polimérica durante el mezclado en fundido de polipropileno. La síntesis in-situ se realiza mediante la descomposición térmica de una sal de cobre y la reducción química de esta sal por acción de un agente químico, ambos a distintos porcentajes de cobre en la carga. Además, se busca caracterizar las partículas de cobre de los materiales preparados, comprobar sus capacidades antifouling dependiendo de la salinidad y la temperatura del agua en que se sumerja y comparar con nanopartículas de cobre comercial. Los resultados obtenidos permitieron validar la metodología planteada y comprobar que es posible obtener partículas de cobre sintetizadas in-situ. Se verificó que los materiales fabricados son capaces de liberar iones cúpricos (Cu2+) en un medio acuoso, lo que varía según el tipo de partícula que contenga cada compósito. Los compósitos preparados por metodología in-situ alcanzaron concentraciones de iones cúpricos liberados mayores a las obtenidas con nanopartículas de cobre pre-sintetizadas, acentuándose a mayor porcentaje de cobre p/p en la mezcla. Al modificar las variables de salinidad y temperatura se presentaron cambios que dependen de la naturaleza de las partículas contenidas en el material. Al aumentar la temperatura del medio disminuyó la cantidad de iones liberados, y al aumentar la salinidad se benefició la liberación de iones por parte de las partículas de cobre metálico, pero se perjudicó en el caso de los óxidos. En los estudios antifouling, los compósitos sugieren una alteración del metabolismo de las células bacterianas, pese a no haber eliminado totalmente la colonización de microflora. Esta nueva metodología abre puertas para la producción de materiales antifouling con cobre de forma sencilla y a bajos costos, otorgando una variedad de nuevas aplicaciones como las mallas para jaulas en la industria acuícola.

Biofouling is a significant economic problem, particularly for marine and offshore oil industries. The acorn barnacle (Amphibalanus (Balanus) amphitrite) is the main biofouling organism in marine environments. Environmental conditions, the physiology of the biofouling organism, the surrounding microbial community, and the properties of the substratum can all influence the attachment of biofouling organisms to substrates. My dissertation investigated the biological processes involved in B. amphitrite development and attachment in the unique environment of the Red Sea, where the average water surface temperature is 34°C and the salinity reaches 41‰. I profiled the transcriptome and proteome of B. amphitrite at different life stages (nauplius II, nauplius VI, and cyprid) and identified 65,784 expressed contigs and 1387 expressed proteins by quantitative proteomics. During the planktonic stage, genes related to osmotic stress, salt stress, the hyperosmotic response, and the Wnt signaling pathway were strongly up-regulated, hereas genes related to the MAPK pathway, lipid metabolism, and cuticle development were down-regulated. In the transition from the nauplius VI to cyprid stages, there was up-regulation of genes involved in blood coagulation, cuticle development, and eggshell formation, and down-regulation of genes in the nitric oxide pathway, which stimulates the swimming and feeding responses of marine invertebrates. This system-wide integrated approach elucidated the development and attachment pathways important in B. amphitrite. Enzymes and metabolites in these pathways are potential molecular targets for the development of new antifouling compounds.

Biomaterials used in biomedical implants, diagnostic devices, and in-situ sensors, all face the issue of biofouling. Surface modification of biomaterial surfaces with antifouling polymers can prevent non-specific adsorption of proteins and other bio-foulants onto these surfaces. Although there are many antifouling polymers to chose from, getting the polymers onto different materials is challenging as the surface modification process is dependent on the substrate’s surface chemistry. This limits the kinds of materials that are able to be modified, especially in devices made with several materials that must be modified as a single unit. Therefore, the goal of this research is to develop an effective antifouling surface modification that is compatible with different types and classes of biomaterials. A three-step modification approach was taken to form dense antifouling polymer brushes. The surfaces were first activated using oxygen plasma to increase the density of surface hydroxyl groups. Next, a silane coupling agent with an Atom Transfer Radical Polymerization (ATRP) initiator was attached to the activated surfaces. Finally, an antifouling zwitterionic monomer was polymerized on the surface using an aqueous controlled living radical polymerization technique, Surface Initiated - Activators Regenerated by Electron Transfer – Atom Transfer Radical Polymerization (SI-ARGET-ATRP). Two zwitterionic antifouling polymers, poly(carboxybetaine methacrylate) (pCBMA), and poly(sulfobetaine methacrylate) (pSBMA) were investigated. Clinically- and environmentally-relevant materials were studied and include poly(dimethylsiloxane) (PDMS), poly(ether ether ketone) (PEEK), titanium, silicon, and 3D printed stainless steel. Water contact angle (WCA) analysis showed that surfaces modified with zwitterionic polymers became more hydrophilic. WCA analysis may not be suitable for evaluating non-modified 3D printed surfaces due to their poor surface finish, and this material requires further surface topography characterization. Atomic force microscopy (AFM) and ellipsometry showed that the zwitterionic polymer layers did not necessarily have to be thick to produce their hydrophilic effect. AFM also revealed that each step of the surface modification process produced different roughness effects on all of the different surfaces. The zwitterionic layer with the smoother surface tended to better resist bovine serum albumin (BSA) adsorption. Radiolabelled BSA experiments showed reduced fouling on all 2D samples but to different degrees. The pCBMA modification was not successful in preventing BSA fouling on 3D printed 316L stainless steel. Full or partial BSA fouling may be due to the hydrolytic instability of the silane coupling agent, used to form covalent bonds between the antifouling polymers and the different surfaces, although further investigation is required to validate this hypothesis. Improving the long-term stability of silanes or research with other multi-surface compatible coupling agents that have better long-term stability in aqueous solutions should be pursued. / Thesis / Master of Applied Science (MASc)

No description available.

Materials in contact with the biological milieu (biomaterials) spontaneously and nonspecifically adsorb constituent proteins which may lead to unwanted cell adhesion and responses or hinder device performance. These interactions and their related phenomena lead to complications in ~3% of implant surgeries. Thus, resistance to these nonspecific interactions is critical to the performance of many implanted biomaterials and biosensing surfaces. Further, these interactions have widespread importance to industrial materials in contact with biological environments such as food packaging, and agricultural and nautical surfaces. Thin film coatings of antifouling polymers are one of the leading methods for reducing nonspecific interactions. Both polymer composition (chemical composition and molecular weight) and polymer grafting density are the principal determinants of coating performance. For applications requiring specific bioactivity, such as selective ligand-analyte interactions for sensors, the polymer coating must remain antifouling and be amenable to functionalization with capture ligands. Tethered polymer coatings can be made by surface initiated polymerization (“graft-from”) which results in higher density coatings, but complex fabrication limits commercialization and capacity of functionalization with capture ligands. Simpler “graft-to” procedures, where pre synthesized polymers are immobilized to a surface, are more amenable to translation but suffer from inferior antifouling properties due to lower density coatings. New fabrication methods are therefore required to improve both graft-to and graft-from coatings. Herein, the effects of polymer density on material performance are explored and leveraged to produce novel functional surfaces using two classes of polymers, namely amphiphilic and thermoresponsive poly(oligo(ethylene glycol)) methyl ether methacrylate, and zwitterionic, functionalizable poly(carboxybetaine methacrylamide) (pCB), as well as copolymers thereof. Specifically, polymer grafting techniques which exploit grafting density effects on surfaces were developed, leading to surfaces: 1) that are both high-loading and antifouling due to two different grafting densities within bimodal architectures, and (2) with enhanced anti-fouling properties despite being prepared via a “grafting-to” method using shrinkable or expandable substrates. Interestingly, shrinking substrates with antifouling polymers resulted in a novel LSPR biosensor with high translation potential. Chapter 2 describes the pH controlled, one-pot production of two-layer brushes composed of an antifouling dense layer and a high-loading lower density layer where capture ligand immobilization was improved by 6 times compared to a single high density layer. Towards improving fouling and bioactivity of graft-to surfaces, Chapter 3 describes the first demonstration of Graft-then-Shrink where a stretched polystyrene (PS) substrate coated in a thin gold layer modified with thiol-terminated pCB was thermo-shrunk to one sixth in footprint to increase polymer surface coating content for enhanced antifouling properties and the production of micro/nano gold wrinkles to generate a localized surface plasmon resonance (LSPR) active surface. The low-cost sensors can vi detect biomolecular interactions by tracking changes in absorbance in the visible spectrum using ubiquitous plate readers. In Chapter 4, Graft-then-Shrink was extended to elastomeric materials, where thiol terminated polymers were grafted onto solvent swollen silicone via thiol-maleimide click chemistry, producing strongly antifouling materials. Taken together, these developments represent significant advances in the preparation and application of antifouling polymer coatings towards the improvement of antifouling surface properties of medical devices and resulted in the development of a novel, low-cost LSPR sensor without the need for specialized equipment. / Thesis / Doctor of Philosophy (PhD) / When a material, such as a medical implant or sensor, is placed in contact with tissues and biological fluids, biomolecules stick to the exposed surfaces through nonspecific interactions. It is important to minimize nonspecific interactions because they can lead to bacterial infections, inflammation, implant failure and loss of device performance. Coatings to minimize nonspecific interactions therefore remain an active area of research. In this thesis, we explored new methods to create biomolecule and cell repellent coatings of long, chainlike molecules known as polymers grafted onto surfaces. Specific types of polymers, known as antifouling, were particularly effective at reducing these interactions. Although it is important to block nonspecific interactions, many devices require bioactive surfaces through selective interactions. For example, sensors for analysis of blood products require the selective binding of the target ligand with minimal binding of non-target agents. To this end, functionalizable antifouling polymers are often modified with a capture or binding agent corresponding to the target ligand. Polymer coatings which are both antifouling and functionalizable for specific interactions, are called “romantic” because of their selective love of a single interaction. To synthesize these romantic polymer coatings, two main methods have been reported: 1) “grafting-from” where the polymer is grown from the surface, producing a very dense coating, and 2) “grafting-to” where the polymer is synthesized in solution, and then immobilized onto the material surface, which produces coatings of lower density. For antifouling polymer coatings to be as effective as possible, polymers should be tethered densely on the material surface, but to maximize the loading of capture agents, polymer density must be lower to allow for grafting within the layer. Further, the grafting-from method is typically more synthetically challenging hindering commercialization. To improve the selective bioactivity of graft-to and graft-from coatings as well as antifouling properties of graft-to coatings, we present two methods to improve the specific bioactivity of anti-fouling polymer coatings and the first description of Graft-then-Shrink, a method to enhance the antifouling properties of graft-to coatings for medical implants and label-free in vitro sensors. For graft-from coatings, we produced a hierarchical romantic surface that consists of two polymer layers, the lower of which is dense and antifouling, and the upper of which is low-density and can accommodate high-levels of bioactive agents, resulting in a best of both worlds; the density of the layers is controlled by a novel pH controlled polymerization procedure. A method to improve the less labor intensive “grafting-to” strategy was then devised, called “Graft-then-Shrink” where the antifouling polymers are grafted onto a shrinkable material, and then the material is shrunk, leading to an increase in grafted polymer content over grafting-to alone. This method was successfully applied to a heat shrinkable material and an elastomeric silicone material, a common material for medical devices, for improved antifouling properties. Finally, a method for combining the Graft-then-Shrink technique iv with a novel localized surface plasmon resonance (LSPR) biosensor was found, that provides a simple route to access romantic surfaces on high-sensitivity, easy to fabricate LSPR biosensors. Together, these fabrication methods will simplify and expedite the translation of antifouling and romantic surfaces for medical devices and sensors.

Novel coatings have been designed to solve problems associated with biofouling of marine structures, particularly ship hulls. The best candidates to date are multilayered coatings incorporating silicone rubber technology. These materials are efficient because they exhibit excellent release properties. However, they are very soft and tend to be more susceptible to various forms of mechanical damage. Fundamental analysis of the durability of these coatings has been done using standard laboratory tests. Simulative studies are essential to screen candidates as well as to predict the true life of the systems. The goal of this project was to develop a testing protocol for the evaluation of the durability of elastomeric easy release coatings and to implement it on selected candidate coatings. A brushing apparatus was designed and built to simulate the cleaning processes of ship hulls. Wear was measured with profilometry. The proposed methodology is valuable to study the processes of wear of the coatings, to screen various materials and to identify parameters, either functional or material, which would directly affect their durability. Two groups of candidate coatings were tested: the EXS series and the NRL series. The EXS samples showed better wear resistance than the NRL samples and showed no dependence on the rotational speed of the brushes. The NRL samples showed that increasing the sliding speed resulted in a decrease in wear. An increase in the applied load resulted in increased wear for both sample series. The effect of coating thickness was also investigated and discrimination between the proposed coatings could not be established because the tips of the bristles were sharp and irregular. Scratches matching the path of the brush bristles were observed in the wear scars of both sample types under all load and speed conditions. The NRL samples also exhibited ridges perpendicular to the sliding direction similar to the abrasion pattern. / Ph. D.

Title: Bioactive interfaces between synthetic surfaces and biological fluids Author: Andrés de los Santos Pereira Institute: Institute of Macromolecular Chemistry, Czech Academy of Sciences Supervisor of the doctoral thesis: RNDr. Eduard Brynda, CSc., Institute of Macromolecular Chemistry, Czech Academy of Sciences Abstract: The application in medicine of label-free affinity biosensors, advanced implants, and blood-contacting devices requires that their surfaces resist non-specific protein adsorption (fouling) and associated complications in blood-derived fluids while displaying immobilized bioreceptors that provide specific biofunctionality. The aim of this thesis was to explore the strategies for the preparation of these antifouling bioactive surfaces. Various types of recently developed antifouling polymer brushes were synthesized and evaluated in terms of their ability to prevent fouling from blood plasma (obtained from various commercial sources and individual donors) as well as thrombus formation when contacted with whole blood. Moreover, single-cell force spectroscopy was utilized to characterize the bacterial adhesion force and energy on these polymer brushes, which were significantly reduced in comparison to various reference substrates. The immobilization of bioreceptors was tackled by means of a...

Thesis (MSc)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Biofouling in cooling water systems lead to several problems resulting in reduced efficiency and financial losses. Antifouling coatings present an environmental friendly solution to prevent biofouling alternatively to the current use of toxic chemicals in cooling water systems. In this study biofilm growth in a cooling water system was simulated in a modified flow cell system to evaluate industrial antifouling coatings and biocide-enriched coatings as potential antifouling coatings for metal surfaces. The design of a novel antifouling coating was also attempted. Firstly, analytical methods for biofilm monitoring to evaluate selected antifouling coatings and biocides were optimised. Pseudomonas sp. strain CT07 was selected to grow biofilms in the biofilm studies. A metal alloy of stainless steel and mild steel (3CR12) showed no corrosion after a 24 h biofilm growth and was selected as metal surface for the biofilm growth discs. Sonification for 5 min was determined as the optimum biofilm removal method from the growth discs. After biofilm removal the metal growth discs were stained with the LIVE/DEAD® BaclightTM Bacterial Viability kit. Visualisation by confocal laser scanning microscopy and flow cytometry revealed auto fluorescence signals from metal discs that hindered quantitative and qualitative analysis of the metal substrate. The use of Pseudomonas sp. strain CT07::gfp to grow biofilms on the metal growth discs and the exclusion of the stain SYTO9 from the LIVE/DEAD® BaclightTM Bacterial Viability kit reduced auto fluorescence signals from the metal discs. The industrial coatings containing quaternary ammonium salt (QAC), triclosan (TC) and copper oxide (CUO) respectively, showed the highest antimicrobial activity in the disc diffusion test. The minimum inhibition concentrations for silver nitrate (SN) and copper sulphate (CS) were 432 ppm and 160 ppm respectively. A minimum of 6.25 % of furanone solution (FR) was biocidal in the dilution susceptibility test. Secondly, the metal growth discs were coated respectively with the three selected industrial coatings QAC, TC and CUO and the epoxy biocide-enriched coatings SN, CS and FR and chemically characterised before and after exposure to biofilm formation. The antifouling activity of these coatings was also characterized. Growth media inoculated with Pseudomonas sp strain CT07::gfp was circulated through the modified flow cell system via a multichannel peristaltic pump for 48 h before the coated metal discs were removed and washed to perform chemical or antifouling analysis. All the industrial coatings and biocide enriched epoxy coatings complied with the thermal stability requirements of a cooling water system. Scanning electron microscopy (SEM) imaging and Energy dispersive X-ray spectroscopy (EDX) analysis confirmed that the adhesion properties of industrial coatings TC and QAC in aqueous environments were insufficient and that the copper and silver ions leached out of the biocide-enriched epoxy coatings. The qualitative analyses of the attachment of bacteria on the surfaces of both the industrial and biocide enriched epoxy coatings was confirmed by SEM, CLSM. The attached bacteria were removed and analysed quantitatively through plate counts and flow cytometry. None of the industrial coatings or the biocide incorporated epoxy coatings that were used in this study would therefore be efficient for the use on metal surfaces in cooling water systems. Thirdly, several approaches were followed to synthesise a poly(styrene-alt-maleic anhydride) (SMA) coating, chemically bind a furanone derivative, 2,5-dimethyl-4-hydroxy-3-(2H)-furanone, to the polymer back bone of the SMA coating for the application as an antifouling coating for cooling water systems. The synthesis of SMA was confirmed through 1H NMR and SEC and the synthesis of tert-butyl 2-(2-hydroxyethoxy) ethylcarbamate and 4-(2-(2-(tert-butoxycarbonyl)ethoxy)ethoxy)-4- oxobutanoic acid was confirmed through 1H NMR and ES-MS+. The synthesis of the end furanone derivative product could however not be achieved. / AFRIKAANSE OPSOMMING: Bio-aanpaksels in waterverkoelingsisteme veroorsaak talle probleme wat lei tot verminderde doeltreffendheid en finansiële verliese. Antimikrobiese oppervlakbedekkings verskaf ‘n omgewingsvriendelike oplossing om bio-aanpaksels te voorkom en ‘n alternatief vir die huidige gebruik van giftige chemikalieë in waterverkoelingsisteme. Biofilm groei in waterverkoelingsisteme was nageboots in ‘n gewysigde vloeiselsisteem om industriële aanpakwerende en biopsied bevattende antimikrobiese oppervlakbedekkings as potensiële aanpakwerende beskermingslae vir metaaloppervlaktes te evalueer. Die ontwerp van ‘n nuwe aanpakwerende beskermingslaag is ook ondersoek. Eerstens is analitiese moniteringsmetodes vir bio-aanpaksels op geselekteerde aanpakwerende antimikrobiese oppervlakbedekkings en biosiedes geoptimiseer. Pseudomonas sp. stam CT07 was verkies om bio-aanpaksels te simuleer gedurende hierdie studie. ‘n Metaalalooi van vlekvrye staal en sagte staal (3R12) het geen korrosie getoon na 24 uur se groei van bio-aanpaksels nie en is vir hierdie rede gebruik as metaal vir die bio-aanpaksel groeiplate. Dit was vasgestel dat sonifisering die optimale verwyderingsmetode vir groeiplate was. Na verwydering van bio-aanpaksels was die metaal groeiplate bedek met die LIVE/DEAD® BaclightTM bakteriële lewensvatbaarheid-toestel. Visualisering deur middel van konfokale mikroskopie en vloeisitrometrie het outofluoreserende seine vanaf die metaal groeiplate onthul wat kwantitatiewe en kwalitatiewe analise van die metaal substraat verhinder het. Die gebruik van Pseudomonas sp. stam CT07:gfp om bio-aanpaksels te kweek op metal plate en die uitsluiting van SYT09 van die LIVE/DEAD® BaclightTM bakteriële lewensvatbaarheid-toestel, het die outofluoreserende seine van die metaalskywe verminder. Industriële beskerminglae, wat onderskeidelik Kwaternêre ammonium sout (QAC), triclosan (TC) en koperoksied (CUO) bevat, het die hoogste antimikrobiese aktiwiteit in die skyf-diffusie toets getoon. Die minimum inhibisiekonsentrasies vir silwernitraat (SN) en kopersulfaat (CS) was onderskeidelik 432 dpm en 160 dpm. ‘n Minimum konsentrasie van 6.25% van die furanoonoplossing (FO) is geklassifiseer as ‘n biosied in die oplossingstoets.Tweedens was die metaal groei-skywe bedek met drie industriële beskermingslae QAC, TC en CUO en die epoksie-biosied-verrykte lae SN, CS en FR en chemiesgekarakteriseerd voor en na die vorming van bio-aanpaksel. Die karaktereienskappe van die aktiwiteit van die beskermingslae was ook vasgestel. Opgeloste triptiese soja sop vermeng met Pseudomonas sp strain CT07: gfp was gesirkuleer in die gemodifiseerde vloeisel deur ‘n multikanaal peristaltiese pomp vir 48 uur voordat die beskermde metaalskywe verwyder en gewas is om chemiese en aanpakwerende analise uit te voer. Al die industriële beskermingslae en biosied-verrykte epoksie-beskermingslae het aan die vereistes van termiese stabiliteit van ‘n waterverkoelingsisteem voldoen. Skandeer elektronmikroskopie (SEM) en X-straal spektroskopie (EDX) analise het aangetoon dat die aantrekkingseienskappe van industriële beskermingslae TC en QAC in waterige oplossings onvoldoende was en dat die koper- en silwerione uit die biosiedverrykte epoksie-resin beskermingslae diffundeer. Die kwalitatiewe analise van die aanpaksel van bakterieë op die oppervlaktes van beide industriële en biosied -verrykte epoksie-beskermingslae was bevestig deur SEM en CLSM. Die aangepakte bakterieë was verwyder en kwantitatief geanaliseer deur middel van plaattellings en vloeisitrometrie. Nie een van die industriële beskermingslae of die biosied-bevattende epoksie beskermingslae wat in hierdie studie gebruik is, is dus gepas vir gebruik op metaaloppervlaktes in waterverkoelingsisteme nie. Derdens was verskeie pogings aangewend om ‘n poli(stireen-alt-maleic anhidried) (SMA) beskermingslaag chemies te bind tot ‘n furanoon afgeleide 2.5-demitiel-4-hidroksie-3-(2H)- furanoon, tot die polimeer-ruggraat van die SMA beskermingslaag vir aanwending as ‘n aanpakwerende beskermingslaag vir waterverkoelingsisteme. Die sintese van SMA was bevestig deur 1H NMR en SEC en die sintese van tert-butyl 2-(2-hirdoksie-etoksie) etielkarbamaat en 4-(2- (2-(tert-butoksiekarboniel)etoksie)etoksie)-4-oksobutanoiesesuur was bevestig deur 1H NMR en ES-MS+. Die sintese van die uiteindelike afgeleide furanoon kon egter nie behaal word nie.