Antibacterial composite coatings of MgB2 powders embedded in PVP matrix

P Badica,M Popa,N D Batalu,M Enculescu,M Truccato,M C Chifiriuc,G Gradisteanu Pircalabioru,A Agostino,M A Grigoroscuta,M Burdusel,B Purcareanu,L G Marutescu,L Olariu,A Bicu,V Bonino,L Operti,B G Dumitriu,G Aldica

doi:10.1038/s41598-021-88885-2

Abstract

Three commercial powders of MgB2 were tested in vitro by MTS and LDH cytotoxicity tests on the HS27 dermal cell line. Depending on powders, the toxicity concentrations were established in the range of 8.3–33.2 µg/ml. The powder with the lowest toxicity limit was embedded into polyvinylpyrrolidone (PVP), a biocompatible and biodegradable polymer, for two different concentrations. The self-replenishing MgB2-PVP composite materials were coated on substrate materials (plastic foil of the reservoir and silicon tubes) composing a commercial urinary catheter. The influence of the PVP-reference and MgB2-PVP novel coatings on the bacterial growth of Staphylococcus aureus ATCC 25923, Enterococcus faecium DMS 13590, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, in planktonic and biofilm state was assessed in vitro at 6, 24, and 48 h of incubation time. The MgB2-PVP coatings are efficient both against planktonic microbes and microbial biofilms. Results open promising applications for the use of MgB2 in the design of anti-infective strategies for different biomedical devices and systems.

Highlights

Three commercial powders of MgB2 were tested in vitro by MTS and Lactate dehydrogenase (LDH) cytotoxicity tests on the HS27 dermal cell line
Concentrations of MgB2 solutions below 8.3, 33.2, and 33.2 μg/ml for the powders Laboratories Inc (LTS), Alfa Aesar, and Cerac are compatible with the metabolism of fibroblasts without a toxic impact
For design purposes of the M gB2-PVP coatings, apart from the as-evaluated cytotoxicity concentrations, we considered the minimum inhibitory concentrations for the growth in the presence of LTS, Alfa Aesar and Cerac MgB2 powders of different reference microbes (Staphylococcus aureus ATCC 25923, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231) in the planktonic (MIC) and biofilm (MICB) states reported in Ref.[23]

Summary

Introduction

Three commercial powders of MgB2 were tested in vitro by MTS and LDH cytotoxicity tests on the HS27 dermal cell line. The opportunistic and nosocomial agents, such as ESCAPE (Enterococcus faecium, Staphylococcus aureus, Clostridium difficile, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacteriaceae) pathogens and Candida albicans represent one of the most important global threats for the public health They have the ability to adhere and develop biofilms on live tissues and implanted medical devices, producing biofilm associated infections[1]. Many physico-chemical properties, such as the type of the nanomaterial, size, morphology, specific surface-area-to-volume ratio, surface charge, concentration, behavior in biological medium and pH, stability and others are conditioning their antibiofilm effect All these factors influence the contact with the biofilm matrix and biofilm embedded cells, affecting the release of reactive oxygen species, of antimicrobial ions or of the loaded bioactive compounds[11]. They can interact with the planktonic cells, inhibiting either the initial adhesion to a substrate and the dispersion, or with the biofilm matrix by facilitating the biofilm penetration, drug release, or further interaction with the biofilm c ells[13]

Results

Discussion

Conclusion