Quality-by-Design-Guided Reactive Oxygen Species-Responsive Antimicrobial Nanotheranostics for Biofilm Eradication: A...

Biofilm-associated infections remain a major therapeutic challenge due to extracellular polymeric substance (EPS) barriers, metabolic heterogeneity, and hypoxic microenvironments that limit antimicrobial penetration and efficacy. Antimicrobial nanotheranostics have emerged as multifunctional platforms that combine targeted drug delivery, diagnostic imaging, and stimuli-responsive therapeutic activation to overcome these barriers.

Reactive oxygen species (ROS)-responsive and oxygen-modulating nanoplatforms represent a promising strategy for biofilm eradication by enhancing oxidative antibacterial activity and improving therapeutic penetration within complex biofilm environments. However, their clinical translation remains constrained by challenges related to reproducibility, scalability, safety, and regulatory compliance. This review addresses these limitations through the integration of Quality-by-Design (QbD) principles into antimicrobial nanotheranostic development.

Recent advances in ROS-responsive and oxygen-regulating nanotheranostic systems are critically examined, with emphasis on the interdependence of hypoxia and ROS generation. The review highlights oxygen-carrying and oxygen-generating nanoplatforms, stimuli-responsive therapeutic strategies, and imaging-guided approaches for biofilm eradication. Furthermore, a QbD-based framework is presented, focusing on Quality Target Product Profiles (QTPPs), Critical Quality Attributes (CQAs), Critical Material Attributes (CMAs), and Critical Process Parameters (CPPs). Functional CQAs, including ROS generation kinetics, oxygen modulation efficiency, and biofilm penetration depth, are identified as key determinants of therapeutic performance and reproducibility.

The integration of ROS-responsive nanotheranostics with QbD principles provides a rational strategy for developing clinically translatable antibiofilm therapies. Defining performance-linked quality attributes and robust design spaces can improve reproducibility, safety, scalability, and regulatory compliance, thereby accelerating the development of next-generation antimicrobial nanotheranostic systems for persistent biofilm-associated infections.