Surface modification of silicone with colloidal polysaccharides formulations for the development of antimicrobial urethral catheters

• Published in: Applied surface science Vol. 463; pp. 889 - 899
• Main Authors: Bračič, Matej, Šauperl, Olivera, Strnad, Simona, Kosalec, Ivan, Plohl, Olivija, Zemljič, Lidija Fras
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2019
• Subjects: Antibacterial; Antifouling; Catheters; Coating; Polysaccharides; Silicone; Polysaccharides; Coating; Antibacterial; Antifouling; Catheters; Silicone
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2018.09.015

[Display omitted] •A discontonuous 3-step dip-coating process of silicone tubes allows for a uniform coating.•A controled release of the polysaccharide-based coatings is observed during one week.•The polysaccharide-based coatings are stable against mechanical abrasion.•The polysaccharide based coatings are antimicrobial and reduce biofilm formation. In this work, surfaces of casted silicone sheets and silicone tubes were functionalized with colloidal polysaccharide complexes (chitosan, carboxymethyl chitosan, and hyaluronic acid in combination with a lysine-based surfactant) in order to introduce antimicrobial and antifouling surface properties. The surface chemistry and morphology, as well as the chemical and mechanical stability of the coatings were characterized. For this purpose, different microscopic and spectroscopic methods, pH-potentiometric titrations and standard methods for evaluation of mechanical properties were used. Finally, the antimicrobial and antifouling properties of functionalized silicone materials were evaluated in vitro. The findings of the physicochemical characterization showed that a discontinuous 3-step dip-coating process can be successfully implemented to coat casted polydimethylsiloxane sheets and tubes with colloidal polysaccharide complexes. These coatings exhibit slow-release leaching in aqueous environment at pH 4.5, 7, and 8 and show very good stability against mechanical abrasion, thus displaying high stability potential during catheter insertion. The antimicrobial properties against gram-positive bacteria, gram-negative bacteria and fungi, showed inhibition of bacterial growth of up to 86%. Furthermore, the bacterial biofilm formation tests have revealed that the hyaluronic acid-surfactant coating exhibits high biofilm growth reduction.