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Schilardi, P. L.

Publications and source records attributed to Schilardi, P. L..

2 recordsLinked to original sources

Anti-Biofouling Albumin Amyloid Coatings Enable Vancomycin-Mediated Bacterial Eradication on Medical Tubing.

Indwelling medical devices such as catheters and endotracheal tubes are major drivers of hospital-acquired morbidity and mortality due to bacterial colonization. The resulting healthcare-associated infections (HAIs) are further exacerbated by rising antimicrobial resistance, underscoring the urgent need for strategies that both prevent biofilm formation and reduce reliance on antibiotics. Polyvinyl chloride (PVC), a widely used material in medical tubing, is highly prone to bacterial attachment, making it a critical target for intervention. Here, we show that complete eradication of Staphylococcus aureus--both sessile on PVC and planktonic--can be achieved using a bovine serum albumin (BSA) amyloid-like coating in combination with vancomycin at a dose eight times lower than the MIC. While the amyloid film alone markedly reduces bacterial adhesion, the residual bacterial load still reaches infection-risk thresholds. This dual approach therefore not only prevents biofilm development but also significantly lowers antibiotic requirements, reducing the risk of resistance emergence and improving therapeutic safety. The coatings, deposited on PVC and on glass (as a model surface), were synthesized using dithiothreitol (DTT) as a reducing agent, as alternative to tris(2-carboxyethyl)phosphine (TCEP). Through optimization of the synthesis, the resulting films preserved their physicochemical and anti-biofouling properties while offering a simple, low-cost, and scalable approach. The coatings strongly adhere to both substrates, remain stable under aqueous and mechanical stress, and effectively suppress bacterial and mammalian cell adhesion without cytotoxicity. These properties are clinically relevant, reducing infection risk and mitigating tubing failure due to fibrous capsule formation, encasement, or crystallized biofilm-induced blockage. The demonstrated biocompatibility, robustness, and scalability of this coating platform underscore its translational potential as a clinically relevant strategy to mitigate HAIs, extend the functional lifetime of medical tubing, and alleviate the global burden of antimicrobial resistance.

bioengineering↗

Antimicrobial nanolayers of thymol and carvacrol on titanium surfaces: the crucial role of interfacial properties in thymol's superior osteogenic response

"Green nanotechnologies have emerged as environmentally friendly alternatives against microbial multidrug-resistant biofilms. In this study, bactericidal "green" nanolayers (NL) were developed on Ti surfaces using two isomeric phytocompounds, carvacrol (Carv-Ti-NL) and thymol (TOH-Ti-NL). These NLs were fabricated using a one-step immersion treatment method based on a simple and spontaneous self-assembly process. Both NLs revealed strong antimicrobial activity, displaying anti-biofilm and biocidal effects. Notably, TOH-Ti-NL exhibited superior osteogenic performance compared to Carv-Ti-NL, as evidenced by enhanced pre-osteoblast cell attachment and growth, and the production of ALP, collagen type I and Ca2+ deposition. In contrast, fibroblastic cells exhibited reduced attachment on TOH-Ti-NL and enhanced proliferation on Carv-Ti-NL. Considering the biological differential effects, the physicochemical properties of these conformational isomers NLs were studied to elucidate potential differences that could impact on cell response. Although the ATR-FTIR spectra of the NLs were similar and indicated the spontaneous oxidation of Carv and TOH leading to ketonic structures, distinct contributions were observed after the electrooxidation of each NL. Slight differences in hydrophilicity were found for both nanostructures, but higher roughness was found for TOH-Ti-NL. Furthermore, the release curves of Carv and TOH from the NLs revealed distinct profiles over time. Overall, Carv and TOH formed self-assembled layers on Ti able to eradicate Staphylococcus aureus biofilms. Their different physical and chemical characteristics induced distinct responses from eukaryotic cells attached to the NLs. Given these characteristics one might envisage the use of either Carv-Ti-NL or TOH-Ti-NL in order to fine-tune specific chemical physical properties of Ti-based implants. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=132 SRC="FIGDIR/small/610464v1_ufig1.gif" ALT="Figure 1"> View larger version (66K): org.highwire.dtl.DTLVardef@1c288f5org.highwire.dtl.DTLVardef@adc72corg.highwire.dtl.DTLVardef@ef2763org.highwire.dtl.DTLVardef@102d823_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗