Epi‐Endocytic Performance Engineering through Nanomaterials Co‐Challenging: A Study of Mechanism and Implication in Radiotherapy

While the influence of size on nanomaterial uptake has been extensively explored, it remains elusive how cells simultaneously respond to multiple, size‐varying particles due to the lack of a proper quantitative assay. In this study, a strategy named “metal‐doping engineering” is developed, and constructed a library of multi‐elemental alloys (MEAs) features precisely controlled size and dopant dosage for quantification with mass spectra. Next a comprehensive study of cellular uptake behaviors is conducted when treated with dual‐, triple‐, and quadra‐, size‐differing nanoparticles. Specifically, the exposure to triple‐, and quadra‐, size‐differing MEAs resulted in an unprecedented, enhanced uptake of counterpart in the middle size as 10/20 nm. Further efforts including RNA‐sequencing and photo‐affinity labeling‐assisted proteomics are devoted to uncovering the underlying mechanism, wherein the role of nonconical endocytic pathways in fast‐endophilin‐mediated endocytosis is uncovered. Given the capacity of MEAs as chaperones to facilitate the uptake of one featuring a predetermined size promoted to propose a straightforward, “bystander nanomaterials”‐assisted drug delivery strategy, whose superior dosage‐reduced radio‐sensitization performance and anti‐tumoral outcome are confirmed in vivo. Uptake profiles of cells facing multiple nanomaterials that differ in size are analyzed through quantitative assay harnessing an approach of metal‐doping engineering. Endocytosis of nanomaterials featuring a moderate size within the mixture unprecedentedly benefits from the bystander counterparts‐induced fast endophilin‐mediated endocytic pathway activation, both in vitro and in vivo with improved therapeutic outcomes.