Detecting bacteria—Listeria monocytogenes—is an essential healthcare and food industry issue. The objective of the current study was to apply platinum (Pt) and screen-printed carbon (SPCE) electrodes modified by molecularly imprinted polymer (MIP) in the design of an electrochemical sensor for the detection of Listeria monocytogenes. A sequence of potential pulses was used to perform the electrochemical deposition of the non-imprinted polypyrrole (NIP-Ppy) layer and Listeria monocytogenes-imprinted polypyrrole (MIP-Ppy) layer over SPCE and Pt electrodes. The bacteria were removed by incubating Ppy-modified electrodes in different extraction solutions (sulphuric acid, acetic acid, L-lysine, and trypsin) to determine the most efficient solution for extraction and to obtain a more sensitive and repeatable design of the sensor. The performance of MIP-Ppy- and NIP-Ppy-modified electrodes was evaluated by pulsed amperometric detection (PAD). According to the results of this research, it can be assumed that the most effective MIP-Ppy/SPCE sensor can be designed by removing bacteria with the proteolytic enzyme trypsin. The LOD and LOQ of the MIP-Ppy/SPCE were 70 CFU/mL and 210 CFU/mL, respectively, with a linear range from 300 to 6700 CFU/mL.

This study addresses the need for enhanced antimicrobial properties of electrospun membranes, either through surface modifications or the incorporation of antimicrobial agents, which are crucial for improved clinical outcomes. In this context, chitosan—a biopolymer lauded for its biocompatibility and extracellular matrix-mimicking properties—emerges as an excellent candidate for tissue regeneration. However, fabricating chitosan nanofibers via electrospinning often challenges the preservation of their structural integrity. This research innovatively develops a chitosan/polycaprolactone (CH/PCL) composite nanofibrous membrane by employing a layer-by-layer electrospinning technique, enhanced with silver nanoparticles (AgNPs) synthesized through a wet chemical process. The antibacterial efficacy, adhesive properties, and cytotoxicity of electrospun chitosan membranes were evaluated, while also analyzing their hydrophilicity and nanofibrous structure using SEM. The resulting CH/PCL-AgNPs composite membranes retain a porous framework, achieve balanced hydrophilicity, display commendable biocompatibility, and exert broad-spectrum antibacterial activity against both Gram-negative and Gram-positive bacteria, with their efficacy correlating to the AgNP concentration. Furthermore, our data suggest that the antimicrobial efficiency of these membranes is influenced by the timed release of silver ions during the incubation period. Membranes incorporated starting with AgNPs at a concentration of 50 µg/mL effectively suppressed the growth of both microorganisms during the early stages up to 8 h of incubation. These insights underscore the potential of the developed electrospun composite membranes, with their superior antibacterial qualities, to serve as innovative solutions in the field of tissue engineering.

The present study demonstrates a strategy for preparing porous composite fibrous materials with superior biocompatibility and antibacterial performance. The findings reveal that the incorporation of PEG into the spinning solutions significantly influences the fiber diameters, morphology, and porous area fraction. The addition of a hydrophilic homopolymer, PEG, into the Ch/PLA spinning solution enhances the hydrophilicity of the resulting materials. The hybrid fibrous materials, comprising Ch modified with PLA and PEG as a co-solvent, along with post-treatment to improve water stability, exhibit a slower rate of degradation (stable, moderate weight loss over 16 weeks) and reduced hydrophobicity (lower contact angle, reaching 21.95 ± 2.17°), rendering them promising for biomedical applications. The antibacterial activity of the membranes is evaluated against Staphylococcus aureus and Escherichia coli, with PEG-containing samples showing a twofold increase in bacterial reduction rate. In vitro cell culture studies demonstrated that PEG-containing materials promote uniform cell attachment, comparable to PEG-free nanofibers. The comprehensive evaluation of these novel materials, which exhibit improved physical, chemical, and biological properties, highlights their potential for biomedical applications in tissue engineering and regenerative medicine.

The dynamically developing field of implantology requires researchers to search for new materials and solutions. In this study, TiNbZr samples were investigated as an alternative for popular, but potentially hazardous TiAl6V4. Samples were etched, sandblasted, subjected to PEO, and covered in AgNP suspension. Simultaneously, SEM images were taken, and the wettability and roughness of the surface were measured. Samples covered in AgNPs were subjected to biological trials. A six-day measurement of human fibroblast proliferation was conducted to assess biocompatibility, and the population of E. coli and S. aureus was measured over eight hours. Results showed that the TiNbZr PEO surface is biocompatible with human fibroblast cells and promotes growth. However, deposited AgNPs exhibited only slight effectiveness in decreasing bacterial growth over the first two hours. The results suggest that the method of surface preparation is sufficient and might promote osseointegration. On the other hand, more efficient and reliable methods of application of AgNPs should be researched

MXenes are well-known as highly biocompatible two-dimensional nanomaterials with a wide range of biomedical applications, including antibacterial strategies. However, the coexistence of high biocompatibility and reported strong antibacterial effects presents a fundamental contradiction that requires critical evaluation. In this study, we systematically investigated the antibacterial properties of pure Ti3C2Tx, Nb2CTx, V2CTx, and Ti3CNTx MXenes of varying flake sizes using multiple in vitro assays and an in vivo wound model. High-resolution structural and chemical characterizations confirmed the use of high-quality, minimally oxidized MXene samples with well-defined surface terminations. Despite using multiple evaluation methods, including disk diffusion, broth microdilution, time-kill kinetics, ROS quantification, and electron microscopy, no significant antibacterial effects were observed at sub-toxic concentrations. Furthermore, neither reactive oxygen species-mediated damage nor the hypothesized “nano-knife” mechanical disruption mechanism could be confirmed. This suggests that the previous observations of antibacterial properties resulted from incomplete removal of etching products or partial oxidation of MXenes. In contrast, we demonstrate that MXene-assisted photothermal therapy (PTT) under near-infrared laser irradiation offers highly effective and selective bacterial ablation. Ti3C2Tx MXene exhibited strong photothermal performance, achieving complete bacterial killing in vitro and significant wound healing efficacy in an in vivo murine model. Targeted PTT using antibody-functionalized MXenes enabled the eradication of E. coli while sparing non-target bacteria. These findings suggest that while intrinsic antibacterial properties of pristine MXenes are limited, their biocompatibility and photothermal responsiveness make them promising platforms for next-generation, externally triggered antibacterial therapies.