Versatile Polypeptide-Functionalized Plasmonic Paper as Synergistic Biocompatible and Antimicrobial Nanoplatform

Abstract

Nowadays, thanks to nanotechnological progress, which itself guides us more and more closely toward not only the efficient design of innovative nanomaterials or nanostructures, but to the improvement of their functionality, we benefit from an important asset in the battle against pathogenic illnesses. Herein, we report a versatile biocompatible plasmonic nanoplatform based on a Whatman paper incorporating positively-charged gold nanospherical particles via the immersion approach. The morphological characterization of the as-engineered-plasmonic paper was examined by SEM (scanning electron microscopy) and HRTEM (high-resolution transmission electron microscopy) investigations, while its surface chemical modification with a synthetic polypeptide, specifically RRWHRWWRR-NH2 (P2), was proved by monitoring the plasmonic response of loaded gold nanospheres and the emission signal of P2 via fluorescence spectroscopy. The as-functionalized plasmonic paper is non-cytotoxic towards BJ fibroblast human cells at bactericidal concentrations. Finally, the antimicrobial activity of the P2-functionalized plasmonic paper on both planktonic bacteria and biofilms was tested against two reference strains: Gram-positive Bacteria, i.e., Staphylococcus aureus and the Gram-negative Bacteria, i.e., Escherichia coli, determining microbial inhibition of up to 100% for planktonic bacteria. In line with the above presented nanoplatform’s proper design, followed by their functionalization with active antimicrobial peptides, new roads can be open for determining antibiotic-free treatments against different relevant pathogens.

Nanocomposite Hydrogel Films Based on Sequential Interpenetrating Polymeric Networks as Drug Delivery Platforms

“…We also performed microscopy experiments to evaluate BJ cell morphology for the conditions where the viability was above 50% (Figure 11). From Figure 10, it can be observed that BJ cell morphology for control cells is similar to data reported previously [37]. BJ control cells exhibit an elongated morphology, with actin filaments almost parallel, stretching from one end to the other end of the cell (Figure 11A).…”

“…Based on the results obtained for the five samples, we can conclude that some traces of zinc acetate can cause toxicity to healthy cells following the preparation steps [76]. The purification procedure after synthesis can be tuned to reduce the cytotoxicity by subject- From Figure 10, it can be observed that BJ cell morphology for control cells is similar to data reported previously [37]. BJ control cells exhibit an elongated morphology, with actin filaments almost parallel, stretching from one end to the other end of the cell (Figure 11A).…”

“…Cell metabolic activity of BJ cells was assessed by MTT assay (Serva), as described previously [37]. The cells were seeded in 24-well plates at a density of 20,000 cells/well for MTT assay or on a 12 mm diameter cover glass for microscopy experiments.…”