The escalating global concern regarding plastic waste accumulation and its detrimental environmental impact has driven the exploration of sustainable alternatives to conventional petroleum-based plastics. This study investigates the development of antimicrobial blends of bacterial nanocellulose (BNC) derived from plastic waste and polyhydroxyalkanoates (PHB), further enhanced with essential oils. The antimicrobial activity of the resulting BNC/PHB blends was tested in vitro against Escherichia coli, Staphylococcus aureus, and Candida albicans. The incorporation of essential oils, particularly cinnamon oil, significantly enhanced the antimicrobial properties of the BNC/PHB blends. The BNC with 5% PHB blend exhibited the highest antifungal inhibition against C. albicans at 90.25%. Additionally, blends with 2% and 10% PHB also showed antifungal activity, inhibiting 68% of C. albicans growth. These findings highlight the potential of incorporating essential oils into BNC/PHB blends to create effective antimicrobial materials. The study concludes that enhancing the antimicrobial properties of BNC/PHB significantly broadens its potential applications across various sectors, including wound dressings, nanofiltration masks, controlled-release fertilizers, and active packaging.

Plasticized microbial (single cell) proteins (MPs) can be used to produce ductile and flexible plastic films with good oxygen barrier properties. However, as with other hydrogen-bond-forming oxygen barrier materials, like ethylene–vinyl alcohol copolymer (EVOH), they need to be protected from moisture because moisture decreases the oxygen barrier properties. Here, we solved the problem by producing three-layer laminate films that are fully biobased and biodegradable. Two different MP films (originating from a mixed microbial culture and Delftia tsuruhatensis biomass) were sandwiched between two different moisture-shielding polyhydroxyalkanoate (PHA) films (a poly­(3-hydroxybutyrate-co-3-hydroxyvalerate) and a poly­(3-hydroxybutyrate-co-3-hydroxyhexanoate) material). The low-temperature melting features of the PHAs made them suitable for lamination through hot-pressing with the MPs. Liquid-water-resistant and UV-blocking laminates could be obtained, where the individual layers were also possible to delaminate as a possible recycling solution, where the MP layer could potentially be used as a fertilizer and the PHA mechanically recycled into similar or other products or composted. The laminates showed, in the best cases, an oxygen permeability of 2 cm³ mm/(m² day atm) and a water vapor permeability below 0.1 g mm/(m² day). All in all, the concept is promising as a sustainable biobased alternative to today’s fossil-based EVOH-laminate packaging solutions.

Nanotechnology offers new possibilities in molecular diagnostics, with nanoparticles gaining attention as biosensor upgrades. This study evaluates gold-coated silver nanoplates coated with PEG for enhanced protection, aiming to detect Spike protein with higher sensitivity, and emphasizes the importance of considering complex environments and appropriate controls for specific binding and accurate analysis. The sensitivity of antibody-coated PEGAuTSNPs as tools for immunoassays is demonstrated through fibronectin (Fn)– anti-fibronectin binding within an isolated extracellular matrix as a complex and native environment of Fn. Moreover, the optimal functionalization volume of Spike protein was determined (4 µg/mL of PEGAuTSNP). Anti-Spike was added to confirm binding, while the TJP1 protein was used as a negative control. The same experiment was used in the presence of horse serum to simulate a complex environment. According to Localized Surface Plasmon Resonance analysis and Dynamic Light Scattering size measurements, anti-Spike exhibited a stronger affinity for the nanoplates, causing TJP1 to be replaced by the antibody on the nanoplates’ surface. Future research will involve exploring alternative complex environments, filtering larger molecules, and the optimization of immunoassay performance.

The escalating global concern regarding plastic waste accumulation and its detrimental environmental impact has driven the exploration of sustainable alternatives to conventional petroleum-based plastics. This study investigates the development of antimicrobial blends of bacterial nanocellulose (BNC) derived from plastic waste and polyhydroxyalkanoates (PHB), further enhanced with essential oils. The antimicrobial activity of the resulting BNC/PHB blends was tested in vitro against Escherichia coli, Staphylococcus aureus, and Candida albicans. The incorporation of essential oils, particularly cinnamon oil, significantly enhanced the antimicrobial properties of the BNC/PHB blends. The BNC with 5% PHB blend exhibited the highest antifungal inhibition against C. albicans at 90.25%. Additionally, blends with 2% and 10% PHB also showed antifungal activity, inhibiting 68% of C. albicans growth. These findings highlight the potential of incorporating essential oils into BNC/PHB blends to create effective antimicrobial materials. The study concludes that enhancing the antimicrobial properties of BNC/PHB significantly broadens its potential applications across various sectors, including wound dressings, nanofiltration masks, controlled release fertilizers, and active packaging.