Abstract:
Live biotherapeutic products are an emerging novel class of products currently under development to be used for the treatment of clinical challenges such as atopic dermatitis, acne, chronic wounds. Several methods of encapsulation are available to preserve the viability of probiotic bacteria in various harsh environmental conditions. In this work, an innovative microchip electrospinning is developed, which combines microfluidics microchip with electrospinning and enables the preparation of fiber matrices comprising living and functional encapsulated bacteria capable of producing antimicrobial substances. The bacteria are encapsulated into microcapsules, which are immediately within the same process electrospun into hydrophobic fibers. Using confocal microscopy and staining samples with fluorescent dyes, it is confirmed that probiotics are present in fibers. The average concentration of probiotics is 106 bacteria/cm2 in a 1 mm thick matrix. Using an agar overlay assay, it is determined that incorporated probiotics retain their functionality and antimicrobial activity against wound pathogens. This evidence confirms that the electrospun fibers containing microcapsules allow two-way diffusion of substances through pores in fibers (e.g., nutrients in, produced substances out) and support the viability of entrapped bacteria. The electrospun probiotics-loaded fiber matrix developed has potential to be used as a drug delivery system for wound infection treatment.

Keywords:
Microchip electrospinning, Microfluidics, Electrospinning, Probiotics, Wound infection

Abstract:
Wounds and chronic wounds can be caused by bacterial infections and lead to discomfort in patients. To solve this problem, scientists are working to create modern wound dressings with antibacterial additives, mainly because traditional materials cannot meet the general requirements for complex wounds and cannot promote wound healing. This demand is met by material engineering, through which we can create electrospun wound dressings. Electrospun wound dressings, as well as those based on hydrogels with incorporated antibacterial compounds, can meet these requirements. This manuscript reviews recent materials used as wound dressings, discussing their formation, application, and functionalization. The focus is on presenting dressings based on electrospun materials and hydrogels. In contrast, recent advancements in wound care have highlighted the potential of thermoresponsive hydrogels as dynamic and antibacterial wound dressings. These hydrogels contain adaptable polymers that offer targeted drug delivery and show promise in managing various wound types while addressing bacterial infections. In this way, the article is intended to serve as a compendium of knowledge for researchers, medical practitioners, and biomaterials engineers, providing up-to-date information on the state of the art, possibilities of innovative solutions, and potential challenges in the area of materials used in dressings.

Keywords:
wound dressings, drug delivery systems, thermoresponsive hydrogels

Abstract:
Bone repair and regeneration require physiological cues, including mechanical, electrical, and biochemical activity. Many biomaterials have been investigated as bioactive scaffolds with excellent electrical properties. Amongst biomaterials, piezoelectric materials (PMs) are gaining attention in biomedicine, power harvesting, biomedical devices, and structural health monitoring. PMs have unique properties, such as the ability to affect physiological movements and deliver electrical stimuli to damaged bone or cells without an external power source. The crucial bone property is its piezoelectricity. Bones can generate electrical charges and potential in response to mechanical stimuli, as they influence bone growth and regeneration. Piezoelectric materials respond to human microenvironment stimuli and are an important factor in bone regeneration and repair. This manuscript is an overview of the fundamentals of the materials generating the piezoelectric effect and their influence on bone repair and regeneration. This paper focuses on the state of the art of piezoelectric materials, such as polymers, ceramics, and composites, and their application in bone tissue engineering. We present important information from the point of view of bone tissue engineering. We highlight promising upcoming approaches and new generations of piezoelectric materials.

Keywords:
piezoelectricity, scaffolds, smart scaffolds, PVDF, PLLA, PVDF-TRFE, collagen, keratin, tissue engineering, bone tissue engineering, smart medicine, regenerative medicine