The adsorption behavior of the Tet-124 antimicrobial peptide and the Tet-124peptide modified at the C- and N-terminus with the sequence glycine-3,4-dihydroxyphenylalanine-glycine (G-DOPA-G) on titanium surfaces was studied using quartz crystal micro balance with dissipation (QCM-D). At a low pH level(4.75) Tet-124 and Tet-124-G-DOPA-G form rigid layers. This is attributed to the electrostatic interactions of the positively charged lysine and arginine residues in the peptide sequence with the negatively charged titanium oxide layer. At an elevated pH level (6.9) Tet-124 shows a lower mass adsorption at the surface than Tet-124-G-DOPA-G. This is attributed to the interaction of the catechol due to the formation of complexes with the titanium oxide and titanium surface layer. The C terminal and N terminal modification with the sequence G-DOPA-G shows similar adsorption rate and mass adsorption coverage at saturation; however it is presented a more loosely layers on the G-DOPA-G-TeT-124. Fibroblast adhesion and the biocompatibility test of both the surfaces following modification withTet-124-G-DOPA-G and the titanium alloy control showed similar results. In addition, no changes in the adhesion of E. colibacteria due to the modification of the surface were detected

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This work describes the fabrication and evaluation of a transparent hydrogel based spray coating to reduce marine biofouling on glass surfaces. A glycerol based copolymer was synthesized and covalently immobilized by applying a simple spray coating procedure. To test its nonfouling behavior, modified glass surfaces were exposed to different marine fouling species including bacteria, green algae, and blue mussels. For all tested species the coating could considerably reduce the settlement as compared to pristine glass surfaces. The settlement of blue mussels on coated surfaces was additionally compared to polytetrafluoroethylene (PTFE) substrates. The glycerol based copolymer showed an even better resistance against blue mussel adhesion than PTFE. Furthermore, the nonfouling performance of the coating was tested via fibrinogen adsorption after aging coated silica slides under marine conditions. The major aim of this study is to provide an easy synthesis and application procedure for a polyglycerol based nonfouling coating and the evaluation of its nonfouling properties in marine environments

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A desinfecção de amostras de resina acrílica pode ser alcançada através de irradiação de micro-ondas. No entanto, configurações inadequadas podem levar a distorções físicas ou prejudicar o processo de descontaminação. Este estudo tem como objetivo propor um regime de desinfecção por micro-ondas rápido e confiável para amostras de resina acrílica, em conformidade com as normas de esterilidade certificadas, para aplicações experimentais em laboratório. Os espécimes foram submetidos à formação de biofilme monoespecífico de Staphylococcus aureus, Escherichia coli e Candida albicans. O meio fluido tioglicolato foi utilizado para o teste qualitativo de desinfecção durante 14 dias de incubação a 35°C. A rugosidade da superfície, microdureza Knoop, resistência à flexão e estabilidade dimensional também foram avaliadas. Os protocolos de irradiação foram de 3 ou 5 min a 450 W ou 650 W em 250 mL de água destilada. As análises estatísticas foram realizadas considerando α=0,05. Todos os regimes de irradiação foram capazes de desinfetar os espécimes expostos a C. albicans. Apenas o regime de 450 W por 3 min não atingiu a desinfecção das amostras expostas a S. aureus e E. coli. A rugosidade da superfície, estabilidade dimensional e resistência à flexão não foram alteradas por nenhum regime (p>0,05). A microdureza diminuiu em todos os regimes, exceto 450 W por 3 min. A irradiação com 450 W por 5 min em 250 mL de água é um procedimento de desinfecção ideal para amostras de resina acrílica, pois combina potência e tempo de exposição ideais.