Junghun Park

Background: The SARS-CoV-2 pandemic has highlighted niclosamide (NIC) as a promising treatment for COVID-19. However, its clinical application is limited due to its poor water solubility, resulting in low bioavailability. Methods: To address this issue, we developed a AuNP-HA-NIC system, which combines gold nanoparticles with hyaluronic acid to enhance drug delivery. Our comprehensive characterization of the system revealed that hyaluronic acid with specific molecular weights, particularly those exposed to electron-beam irradiation between 2 and 20 kGy, produced the most stable nanoparticles for efficient drug loading and delivery. Results: Additionally, the AuNP-HA-NIC system exhibits a significant sensitivity to pH changes, which is a critical feature for targeted drug release. Under acidic conditions mimicking the stomach and small intestine, minimal drug release was observed, indicating the effective prevention of premature drug release in the gastrointestinal tract. Furthermore, the integration of a targeting aptamer established specific binding abilities towards the SARS-CoV-2 spike protein, distinguishing it from other coronaviruses. Conclusions: As research progresses, and with further in vivo testing and optimization, the AuNP-HA-NIC–aptamer system holds great promise as a game-changer in the field of antiviral therapeutics, particularly in the battle against COVID-19.

Although the personal protective equipment (PPE) used by healthcare workers (HCWs) effectively blocks hazardous substances and pathogens, it does not fully rule out the possibility of infection, as pathogens surviving on the fabric surface pose a substantial risk of cross‐infection through unintended means. Therefore, PPE materials that exhibit effective biocidal activity while minimizing contamination by viscous body fluids (e.g., blood and saliva) and pathogen‐laden droplets are highly sought. In this study, petal‐like nanostructures (PNSs) are synthesized through the vertical rearrangement of colloidal lamellar bilayers via evaporation‐induced self‐assembly of octadecylamine, silica‐alumina sol, and diverse photosensitizer. The developed method is compatible with various fabrics and imparts visible‐light‐activated antimicrobial and superhydrophobic‐based antifouling activities. PNS‐coated fabrics could provide a high level of protection and effectively block pathogen transmission as exemplified by their ability to roll off viscous body fluids reducing bacterial droplet adhesion and to inactivate various microorganisms. The combination of antifouling and photobiocidal activities results in the complete inactivation of sprayed pathogen‐laden droplets within 30 min. Thus, this study paves the way for effective contagious disease management and the protection of HCWs in general medical environments, inspiring further research on the fabrication of materials that integrate multiple useful functionalities.

One-pot synthesis of gold nanoparticles coated with electron beam-irradiated hyaluronic acid was developed to achieve a pH-dependent sulfasalazine release system with high drug encapsulation efficiency.