Size and morphology optimization-driven in vivo targeting of nanomedicines: Mechanisms and characterization techniques.

Nanoparticles (NPs) have promising biomedical applications with great potential for drug delivery, disease diagnosis, and precision therapy. However, the biosafety and delivery efficiency of NPs remain critical bottlenecks. This review systematically examines the in vivo fate of NPs, clarifying their main exposure routes and toxicity effects. Specifically, we analyze the key steps in the systemic circulation transport of NPs, cellular uptake and intracellular transport, and we show the impact of the blood flow microenvironment on the in vivo behavior of NPs by taking full account of fundamental hemodynamic considerations. Size and morphology are the fundamental physical features governing NP tissue distribution, toxic effect intensity, uptake efficiency, and final in vivo fate. The application status of laser light scattering (LLS) methods is discussed here, along with the technical advantages of LLS techniques including dynamic light scattering (DLS). Furthermore, this review introduces the latest research progress in the field of light scattering. In-depth understanding and precise regulation of the physicochemical properties of NPs are the core prerequisites for designing efficient and safe nanomedicine carriers, and are of crucial significance for promoting the clinical translation of nanomedicine. Although the direct application of advanced light scattering techniques to guide in vivo targeted therapy and safety assessment is still in the early exploratory stage, the theoretical framework constructed and characterization strategies proposed in this article provide important theoretical bases and technical ideas for the future development of more intelligent and reliable nanomedicine platforms.