Inhibiting Bacterial Adhesion by Mechanically Modulated Microgel Coatings

Abstract

Bacterial infection is a severe problem especially when associated with biomedical applications. This study effectively demonstrates that poly-N-isopropylmethacrylamide based microgel coatings prevent bacterial adhesion. The coating preparation via a spraying approach proved to be simple and both cost and time efficient creating a homogeneous dense microgel monolayer. In particular, the influence of cross-linking density, microgel size, and coating thickness was investigated on the initial bacterial adhesion. Adhesion of Staphylococcus aureus ATCC 12600 was imaged using a parallel plate flow chamber setup, which gave insights in the number of the total bacteria adhering per unit area onto the surface and the initial bacterial deposition rates. All microgel coatings successfully yielded more than 98% reduction in bacterial adhesion. Bacterial adhesion depends both on the cross-linking density/stiffness of the microgels and on the thickness of the microgel coating. Bacterial adhesion decreased when a lower cross-linking density was used at equal coating thickness and at equal cross-linking density with a thicker microgel coating. The highest reduction in the number of bacterial adhesion was achieved with the microgel that produced the thickest coating (h = 602 nm) and had the lowest cross-linking density. The results provided in this paper indicate that microgel coatings serve as an interesting and easy applicable approach and that it can be fine-tuned by manipulating the microgel layer thickness and stiffness.

Highly Efficient Antimicrobial and Antifouling Surface Coatings with Triclosan-Loaded Nanogels

“… 20 − 22 Recently, our group reported the effect of nanogel size, mechanical properties, and coating thickness on the antifouling behavior toward bacterial adhesion. 13 So far, nanogel coatings have been used for antifouling purposes toward proteins, 23 macrophage adhesion, 24 antifogging and antifrosting performance, 25 enzyme uptake capability for biosensor design, 26 controlling the cell proliferation and cell adhesion, 27 , 28 and controlling antimicrobial and anti-inflammatory properties via peptide-loading. 29 The surface coating preparation with nanogel particles is a facile method and predominantly based on the electrostatic interactions of a pretreated surface and the nanogel surface charge that is induced by the synthesis method.…”

Nanogels with Selective Intracellular Reactivity for Intracellular Tracking and Delivery

“…Hydrogel nanoparticles or nanogels, have been used in various fields of research including catalysis, [8, 9] selective diagnostics and delivery, [10, 11] and anti‐fouling coatings [12, 13] . Even though these nanogels have found their way into the biomedical field, [14, 15] theranostics and multimodalities remain underdeveloped and mostly hybrid structures are being used (inorganic/organic) [16–18] .…”

“…[7] Hydrogel nanoparticles or nanogels, have been used in various fields of research includingc atalysis, [8,9] selectived iagnostics and delivery, [10,11] and anti-fouling coatings. [12,13] Even though these nanogelshave found their wayinto the biomedical field, [14,15] theranostics and multimodalities remainu nderdeveloped and mostly hybrid structuresa re being used (inorganic/organic). [16][17][18] Few examples have been developedt hat rely solely on hydrogel structures [17,[19][20][21][22][23] and when doing so, the multimodality originates from as ingle molecular species, [24] whichl imits the general applicability.…”

Bionanomateriais para o cruzamento de barreira biológica e entrega controlada

“…Nanogels were synthesized by precipitation polymerization as previously described with some adaptations to suit this study purposes. 133 Prior to use, NIPMAM 97% was purified by recrystallization from n-hexane and dried at reduced pressure using a rotary evaporator. The SDS concentration ( Figure S1, Appendix A) and polymerization time ( Figure S2, Appendix A) affect the nanogels size and dispersity and were varied to obtain monodisperse nanogels at 200 and 400 nm range sizes and monodispersity.…”

“…This can possibly be explained by the NGs stiffness variation, where NG1.5 elastic modulus is about 20 kPa and NG5 120 kPa, while NG14 is about 350 kPa, as reported in our earlier work. 133 The lower uptake of soft NPs by macrophages is an indication of longer blood half-life in vivo and often leads to increased accumulation in tissues. As reported by Anselmo et al, not only blood circulation was longer for soft particles, but also organ retention was enhanced, including brain accumulation.…”