Petr Saha

Hydrogels derived from biopolymers have attracted considerable interest in biomedical applications because of their biocompatibility and structural similarity to the extracellular matrix (ECM). Bacterial Cellulose (BC), despite being a promising biopolymer for hydrogel preparation, lacks antimicrobial properties itself. To address this drawback, we prepared Probiotic Bacterial Cellulose (PBC) in our laboratory, which has intrinsic antibacterial properties. No research was found on the preparation of a hydrogel using PBC and κ-carrageenan, which motivated us to develop a PBC/κ-carrageenan-based hydrogel. In the study, a novel biocomposite hydrogel system has been developed by integrating PBC with κ-carrageenan, yielding a multifunctional hydrogel with enhanced antibacterial properties and biocompatibility. The novel hydrogel has been evaluated for its structural, physicochemical, antibacterial, and biocompatible properties. Fourier transform infrared spectroscopy (FTIR) analysis confirmed the formation of intermolecular interactions between PBC and κ-carrageenan. Scanning electron microscopy (SEM) images revealed a porous internal morphology and the presence of probiotic bacteria within the hydrogel networks. Porosity analysis and swelling behaviour indicated an elevated water uptake capacity and structural stability. The composite hydrogel demonstrated promising antibacterial properties against pathogenic bacteria Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) and exhibited favourable in vitro biocompatibility. The developed PBC/κ-carrageenan hydrogel exhibits a synergistic combination of porosity, swelling capacity, biocompatibility, and antibacterial activity, making it a potential candidate for healthcare applications viz. wound healing and other tissue engineering applications.

Supercapacitors (SCs) are highly attractive energy storage devices, and modern research is focused on using waste materials to reduce environmental impact. This study processed biowaste from local brewery production to produce a highly specific mesoporous activated carbon (AC) for SC electrode scaffolds. Polyaniline (PANI) was synthesized and incorporated into the AC scaffold, thereby enhancing performance. The AC and PANI combination (ACP) achieved a specific capacitance of 173.7 F/g at 1 A/g, with 92% retention after 5000 cycles. Using NdFeB (ACN) particles, the anode showed a specific capacitance of 127 F/g and over 99% retention. An asymmetrical ACN//ACP cell demonstrated promising performance with 70% efficiency. This study highlights the potential of using biowaste for high-performance SC electrodes and the effective synergy between AC and PANI.

This study involved the creation of highly porous PLA scaffolds through the porogen/leaching method, utilizing polyethylene glycol as a porogen with a 75% mass ratio. The outcome achieved a highly interconnected porous structure with a thickness of 25 μm. To activate the scaffold’s surface and improve its hydrophilicity, radiofrequency (RF) air plasma treatment was employed. Subsequently, furcellaran subjected to sulfation or carboxymethylation was deposited onto the RF plasma treated surfaces with the intention of improving bioactivity. Surface roughness and water wettability experienced enhancement following the surface modification. The incorporation of sulfate/carboxymethyl group (DS = 0.8; 0.3, respectively) is confirmed by elemental analysis and FT-IR. Successful functionalization of PLA scaffolds was validated by SEM and XPS analysis, showing changes in topography and increases in characteristic elements (N, S, Na) for sulfated (SF) and carboxymethylated (CMF). Cytocompatibility was evaluated by using mouse embryonic fibroblast cells (NIH/3T3).