Younghee Kim

Over the past decade, antibacterial materials have become a promising strategy to address both antibiotic-resistant and biomaterial-associated infections in clinical settings. Despite substantial progress, a gap remains between promising antibacterial performance in vitro and limited therapeutic outcomes in vivo. Herein, we present a mechanistic framework for understanding formulation-dependent antibacterial performance across five representative formulation architectures: nanoparticle-based systems, nanofibrous scaffolds, hydrogel matrices, surface coatings, and vesicular or microencapsulated carriers. We impart how structural organization and delivery dynamics regulate antibacterial mechanisms such as contact-mediated killing, controlled therapeutic release, and reactive oxygen species (ROS) generation and discuss their context-dependent suitability for diverse infection scenarios; these include acute wound infections, biofilm-associated implant infections, and chronic infected wounds. Particular emphasis is placed on factors contributing to the frequent failure of high in vitro log reduction efficacy translating into clinical success, including protein corona formation, biological barrier penetration, and dynamic host–pathogen interactions. Finally, we propose a comparative formulation-selection framework based on infection type, tissue environment, and therapeutic objectives to guide the rational design of next-generation antibacterial materials. This perspective bridges the gap between material innovation and clinical translation by highlighting formulation architecture as a central determinant of antibacterial performance in biomedical applications.

Cellulose nanofibril (CNF)-based hydrogels, owing to their sustainability, biocompatibility, and versatile mechanical properties, are promising for biomedical applications. This review analyzes the recent advances and biomedical applications of CNF hydrogels. CNF hydrogels can be prepared via physical and chemical crosslinking. Physical crosslinking involves surface charge density control, pH manipulation, and flow-based processing to generate stable networks, whereas chemical crosslinking employs agents such as epichlorohydrin and citric acid to form permanent covalent bonds. These approaches enable precise control over hydrogel properties, including mechanical strength, porosity, and stimuli responsiveness. CNF hydrogels are particularly promising in drug delivery systems and tissue engineering. CNFs as drug delivery vehicles offer enhanced bioavailability and drug loading capacity owing to their open pore structure and large surface area. Recent developments in stimuli-responsive and injectable CNF hydrogels have enabled controlled drug release and improved targeting capabilities. Moreover, CNF hydrogels serve as effective scaffolds for cell growth and tissue regeneration, with applications in cartilage engineering and wound healing. Integrating CNF hydrogels with 3D bioprinting technology has generated complex tissue structures. However, several challenges remain, including the need for the standardization of toxicology assessments, optimization of large-scale production processes, and development of sophisticated control mechanisms for drug delivery. Future research should advance manufacturing technologies, improve long-term stability, and develop standardized testing protocols for regulatory compliance.

Cellulose nanofibril (CNF)-based hydrogels, owing to their sustainability, biocompatibility, and versatile mechanical properties, are promising for biomedical applications. This review analyzes the recent advances and biomedical applications of CNF hydrogels. CNF hydrogels can be prepared via physical and chemical crosslinking. Physical crosslinking involves surface charge density control, pH manipulation, and flow-based processing to generate stable networks, whereas chemical crosslinking employs agents such as metal ions, epichlorohydrin, and citric acid to form permanent covalent bonds. These approaches enable precise control over hydrogel properties, including mechanical strength, porosity, and stimuli-responsiveness. CNF hydrogels are particularly promising in drug delivery systems and tissue engineering. CNFs as drug delivery vehicles offer enhanced bioavailability and drug loading capacity owing to their open pore structure and large surface area. Recent developments in stimuli-responsive and injectable CNF hydrogels have enabled controlled drug release and improved targeting capabilities. Moreover, CNF hydrogels serve as effective scaffolds for cell growth and tissue regeneration, with applications in cartilage engineering and wound healing. Integrating CNF hydrogels with 3D bioprinting technology has generated complex tissue structures. However, several challenges remain, including the need for standardizing toxicology assessments, optimizing large-scale production processes, and developing sophisticated control mechanisms for drug delivery. Future research should advance manufacturing technologies, improve long-term stability, and develop standardized testing protocols for regulatory compliance.