Soft Nanocarriers as Antimicrobial Co-Delivery Systems to Combat Resistant Infections

The rise of antimicrobial resistance (AMR) poses a global health challenge, driving the need for innovative solutions to effective treatment and prevention. The advancing field of nanotechnology has facilitated the development of nanocarriers based on polymer and lipid excipients with precisely controlled compositions, release mechanisms, and targeted biological interactions. These "soft" nanocarriers can be tailored to deliver multiple antimicrobial drugs with complementary mechanisms of action, offering an effective strategy to prevent and combat AMR. This review highlights the design and applications of nanocarriers as co-delivery systems, emphasizing their potential for optimized drug loading, spatio-temporal control of release, and pathogen-specific targeting. The unique benefits of diverse nanocarrier types, including lipid-based, polymer-based, and hybrid systems, are covered with a comprehensive set of examples from recent literature in multidrug encapsulation and synergistic antimicrobial therapies. The review also delves into the key challenges in achieving precise control over the sequence and rate of release, ensuring pathogen specificity, and overcoming biological barriers such as biofilms, and provides perspectives on future research efforts to advance nanocarrier engineering and optimization strategies to develop robust, targeted treatments capable of addressing the urgent threat of resistant infections.