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Tantalum (Ta) and its application in biomaterials has been attracting more and more attention recently. It can be considered as a material for hard tissue implants. This study focuses on antimicrobial and surface characterization of micro‐arc oxidized (MAO) nanocrystalline Ta compared with its microcrystalline equivalent. For the purposes of the investigation, x‐ray diffractometry (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), wetting analysis, optical profilometry, corrosion resistance measurement, and antimicrobial tests were performed. Nanocrystalline Ta was fabricated using high‐energy ball milling (HEBM) and pulse plasma sintering (PPS). The MAO process done at 250 V results in the formation of a porous oxide surface. An XRD analysis confirmed the presence of a Ta2O5 oxide layer. Based on the SEM pictures, the obtained oxide layer was approximately 3–4 μm thick for nanocrystalline Ta substrate. For microcrystalline Ta, the oxide layer was thinner, in the range of 0.3–0.6 μm. The analysis of polarization curves showed a significant improvement of corrosion resistance for MAO nanocrystalline Ta (2.62 × 10−8 A/cm2) versus not oxidized nanocrystalline Ta (1.20 × 10−5 A/cm2). The surface roughness of MAO nanocrystalline Ta proved to be several times higher than that of unoxidized Ta. Wetting analysis showed that the oxide layer on the nanocrystalline substrate is hydrophilic. This research provides detailed information about MAO microcrystalline and MAO nanocrystalline Ta antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. A significant decrease of S. aureus for MAO nanocrystalline Ta (control 10,435 ± 981 vs. sample 3,453 ± 130) was noticed. No significant difference was noticed for MAO microcrystalline and nanocrystalline Ta tested for P. aeruginosa.

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Objective: There is a lack of literature on the characteristics and properties of fibre dressings available on the market. This study analysed the structure and absorption properties of different fibrous dressings used in wound treatment. Method: This in vitro experiment was performed using scanning electron microscopy (SEM) and absorption test. Dressings were compared before and after the gelling process which was then compared with the results of the absorption test. Results: A total of five samples were analysed. The SEM analysis demonstrated that there are differences in the gelling processes for each. In some cases, a formation of dead spaces was noticed. Despite a similar structure and mode of action, the dressings have different properties. Results were correlated with absorption measurements. There was a considerable difference in absorption capacity of individual dressings, which may further affect the capacity of the dressing to manage exudate. Conclusion: Absorption of excess exudate and maintaining moisture balance in the wound environment are among the most important conditions of successful healing. Various fibrous dressings have different properties and clinicians should use this information to select the most appropriate dressing for the type of wound.

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