Antibacterial coatings on model silicon wafers and implants, based on chitosan (CHI), poly(acrylic acid) (PAA), and the antibacterial agent chlorhexidine digluconate (CHX), were obtained using a layer-by-layer assembly method. The surface roughness and 2D and 3D images of the surfaces of CHI/PAA/CHX coatings obtained from different pH assemblies were investigated by atomic force microscopy, revealing that pH 6 enabled optimal inclusion of CHX in the multilayer film. The structure and elemental composition before and after implementation of CHX into the coating were investigated via scanning electron microscopy and energy-dispersive X-ray spectroscopy. The obtained films exhibited antimicrobial efficacy against Staphylococcus aureus and Staphylococcus epidermidis. The effects of CHX concentration and duration of contact with the coating on bacterial activity were investigated, and the quantitative release of CHX from coated implants in phosphate buffer was determined as a function of the incubation time. The biocompatibility of the PAA/CHI/CHX coatings was investigated using human mononuclear cells (HMNCs) and quantified using an MTT assay. HMNCs demonstrated high viability in eluted solutions obtained from implants coated with PAA/CHI/CHX (0.025%) and PAA/CHI/CHX (0.0125%), while the extract of implants coated with PAA/CHI/CHX (0.05%) induced slight cytotoxicity.

The physico-chemical studies of produsing nanocoating in the form of multilayers on the basis of chitosan and carboxymethyl cellulose were done. Was justified the use of triclosan, chlorhexidine, silver ions and iodine as potential antibacterial agents in the composition of nano-coating for medical and biological implantable systems. Preliminary studies of antibacterial activity of the resulting multilayers on silicon plate showed good activity against many bacteria.

In this study, hemolytically safe and antibacterial polyvinyl alcohol/kaolinite/chitosan (PVA/KAO/CS) hydrogels were obtained using the freeze–thaw method. The structure of the chemical bonds present in the developed hydrogels was investigated by Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) and optical microscopy study results showed the morphological and structural characteristics of the hydrogels’ surface. The thermal stability and phase transitions of the obtained hydrogel samples were determined by thermogravimetric analysis (TGA). Porosity, swelling, gel fractions, and mechanical properties were also examined. Biomedical properties of the samples were evaluated using in vitro and in vivo tests such as hemolytic activity, inhibition of protein denaturation, antimicrobial activity, and hemostatic activity. The obtained hydrogels demonstrated safe hemolytic activity, pronounced hemostatic activity, the ability to prevent thermal denaturation of albumin, as well as antimicrobial activity against Gram-positive bacteria Staphylococcus aureus ATCC BAA-39 and Streptococcus pyogenes ATCC 19615 and Gram-negative bacteria Pseudomonas aeruginosa ATCC 9027 and Escherichia coli ATCC 8739. All the obtained characteristics confirmed the promising biomedical applications of the obtained hydrogels.

The development of antibacterial coatings for biomedical applications is crucial to prevent implant-associated infections (IAIs). In this study, we designed and evaluated a multilayer coating based on chitosan (CHI), polyacrylic acid (PAA), and triclosan (TCS) using the layer-by-layer (LbL) self-assembly technique. The successful incorporation of TCS was confirmed by Fourier-transform infrared (FTIR) spectroscopy. Surface roughness and topography were analyzed using atomic force microscopy (AFM) and scanning electron microscopy (SEM). Additionally, the pH-dependent behavior of PAA/CHI films was studied to assess its effect on TCS loading. According to disk diffusion assays, coatings assembled at pH 5 (PAA5/CHI5/TCS) exhibited the strongest antibacterial activity, with inhibition zones of 60.0 ± 0.0 mm for S. aureus and 33.67 ± 1.5 mm for E. coli. The long-term stability of the coatings was evaluated by measuring the antibacterial activity after 1, 10, 20, 30, and 40 days, with results confirming that antimicrobial properties and structural integrity were preserved over time. Furthermore, TCS release kinetics were assessed under physiological (pH 7.4) and acidic (pH 5.5) conditions, revealing enhanced release at pH 5.5. These findings highlight the potential of this multilayer system for biomedical applications requiring both stability and pH-responsive drug release.