Little is known about interactions of non-filamentous, complex-structured lytic phages and free, non-ordered nanoparticles. Emerging questions about their possible bio-sanitization co-applications or predictions of possible contact effects in the environment require testing. Therefore, we revealed the influence of various nanoparticles (NPs; SiO₂, TiO₂-SiO₂, TiO₂, Fe₃O₄, Fe₃O₄-SiO₂ and SiO₂-Fe₃O₄-TiO₂) on a T4-like phage. In great detail, we investigated phage plaque-forming ability, phage lytic performance, phage progeny burst times and titers by the eclipse phase determinations. Additionally, it was proved that TEM micrographs and results of NP zeta potentials (ZP) were crucial to explain the obtained microbiological data. We propose that the mere presence of the nanoparticle charge is not sufficient for the phage to attach specifically to the NPs, consequently influencing the phage performance. The zeta potential values in the NPs are of the greatest influence. The threshold values were established at ZP < −35 (mV) for phage tail binding, and ZP > 35 (mV) for phage head binding. When NPs do not meet these requirements, phage–nanoparticle physical interaction becomes nonspecific. We also showed that NPs altered the phage lytic activity, regardless of the used NP concentration. Most of the tested nanoparticles positively influenced the phage lytic performance, except for SiO₂ and Fe₃O₄-SiO₂, with a ZP lower than −35 (mV), binding with the phage infective part—the tail.

Growing interest in bacteriophage research and use, especially as an alternative treatment option for multidrug-resistant bacterial infection, requires rapid development of production methods and strengthening of bacteriophage activities. Bacteriophage adsorption to host cells initiates the process of infection. The rotating magnetic field (RMF) is a promising biotechnological method for process intensification, especially for the intensification of micromixing and mass transfer. This study evaluates the use of RMF to enhance the infection process by influencing bacteriophage adsorption rate. The RMF exposition decreased the t₅₀ and t₇₅ of bacteriophages T4 on Escherichia coli cells and vb_SauM_A phages on Staphylococcus aureus cells. The T4 phage adsorption rate increased from 3.13 × 10⁻⁹ mL × min⁻¹ to 1.64 × 10⁻⁸ mL × min⁻¹. The adsorption rate of vb_SauM_A phages exposed to RMF increased from 4.94 × 10⁻⁹ mL × min⁻¹ to 7.34 × 10⁻⁹ mL × min⁻¹. Additionally, the phage T4 zeta potential changed under RMF from −11.1 ± 0.49 mV to −7.66 ± 0.29 for unexposed and RMF-exposed bacteriophages, respectively.

Hydrophobically modified chitosan has attracted considerable interest as an amphiphilic biomaterial for drug delivery, antimicrobial systems, and tissue engineering. Despite extensive research and promising biological performance, only a limited number of these materials have advanced toward clinically relevant technologies. This Perspective argues that the major barriers to translation are no longer related to biological efficacy but to insufficient reproducibility, inconsistent structural characterization, and limited attention to process engineering and scalable manufacturing. Rather than providing another comprehensive review, we discuss hydrophobically modified chitosan from a translational perspective, following its development from chemical modification and self-assembly to formulation engineering and representative biomedical applications. We highlight how molecular design, processing conditions, and material characterization collectively determine the reliability and practical applicability of these systems. Finally, we outline key priorities for future research, including standardized characterization protocols, harmonized experimental methodologies, and the implementation of engineering-oriented development strategies. We propose that future progress will depend less on introducing new chemical modifications and more on integrating polymer chemistry with process engineering to improve reproducibility and facilitate clinical translation.