Nonresponsive Nanomaterials

Nonresponsive nanomaterials—defined by their capacity to exert antibacterial activity or facilitate drug delivery without reliance on external or internal triggers—have emerged as a promising class of nanotherapeutics for H. pylori eradication. This chapter provides a comprehensive overview of three major categories of non-responsive nanomaterials investigated in this context: lipid-based nanocarriers, polymer-based nanoparticles, and metal and metal oxide nanoparticles. Lipid-based systems, including liposomes, solid lipid nanoparticles, and nanostructured lipid carriers, offer favorable biocompatibility, flexible drug encapsulation, and the ability to protect therapeutic agents from gastric acid degradation while enabling mucosal adhesion or penetration. Polymer-based nanoparticles, particularly chitosan-based systems, synthetic polymers such as PLGA and PEG, and mucoadhesive or muco-penetrating designs, provide tunable physicochemical properties, intrinsic antibacterial activity, and sustained drug release tailored to the challenging gastric environment. Metal and metal oxide nanoparticles—encompassing silver, gold, zinc oxide, and bismuth—exert multifaceted bactericidal effects through ion release, reactive oxygen species generation, and direct structural disruption of bacterial membranes, making them particularly effective against multidrug-resistant strains. Within the integrative "3R" design framework (Remove, Remodel, and Repair), nonresponsive nanomaterials primarily contribute to the "Remove" function while partially supporting "Repair" through mucosal protection and microbiota preservation. For each material category, representative systems, mechanisms of antibacterial action, and preclinical applications are discussed, followed by an analysis of their respective advantages and limitations. The chapter concludes by highlighting key challenges—including gastric stability, long-term biosafety, biofilm penetration, and scalability—and outlines future directions for the rational design of multifunctional, targeted, and clinically translatable nonresponsive nanoplatforms for H. pylori eradication.