How can nanomaterial-based drug delivery systems be more efficient?

Surface Area to Volume Ratio: NPs with higher surface area-to-volume ratios - nanorods & nanowires, provide more surface area for drug loading and interaction with tissues. Cellular Uptake: Rod-shaped NPs may have enhanced cellular internalization compared to spherical nanoparticles due to their elongated structure, facilitating better interaction with cell membranes. Targeting Capabilities: Disc-shaped NPs may exhibit improved targeting of tumor tissues due to their enhanced circulation time & preferential accumulation in tumor microenvironments. In Vivo Behavior: Spherical NPs tend to have longer circulation times in the bloodstream than rod-shaped NPs, which may be more prone to rapid clearance by the reticuloendothelial system.

Enhanced uptake: Smaller NPs exhibit increased surface area-to-volume ratios, promoting efficient cellular internalization & improved drug delivery. Targeting precision: NP size affects biodistribution and extravasation through leaky vasculature, enabling targeted accumulation in tissues Drug loading capacity: Size influences NP payload capacity, with smaller particles typically accommodating lower drug amounts but offering higher surface coverage for controlled release Clearance kinetics: Particle size governs renal excretion and hepatic clearance rates, impacting systemic circulation time & overall pharmacokinetics Immune response modulation: Size dictates interactions with immune cells, & potential immune-mediated clearance or activation

1. Biocompatibility and toxicity: Composition affects interaction with biological systems, influencing biocompatibility & potential toxicity. 2. Stability and degradation: Material choice affects NP stability & degradation rates, impacting drug release kinetics and shelf-life. 3. Targeting ligands: Specific compositions enable conjugation of targeting ligands for enhanced targeting of diseased tissues or cells. 4. Controlled drug release: Composition influences drug release mechanism, enabling tailored release profiles for desired therapeutic effects. 5. Therapeutic payloads: Composition compatibility determines suitability for various therapeutic payloads, including small molecules, proteins, nucleic acids, and imaging agents.

Nanoparticles can be divided into two main types: organic nanoparticles, including liposomes, dendrimers, and polymeric nanoparticles, and inorganic nanoparticles, including mesoporous silica, gold NPs, and carbon nanotubes. These nanoparticles are synthesised in different ways, and the method used significantly impacts their size, structure, morphology, electrochemical, physicochemical, optical, and electrical properties, as well as overall performance. During the synthesis process, the sizes and shapes of these nanoparticles can be controlled based on their intended functionality. The functionalisation of nanoparticles needs to be tailored according to their intended use, the type of nanoparticle, and the functionalisation agents.

Biological barriers: Under normal physiological conditions, effective biodistribution and drug delivery of nanoparticles faces both physical and biological barriers, including shear forces, protein adsorption, and rapid clearance, which limit the fraction of administered nanoparticles that reach the target therapeutic site. Disease states can alter biological barriers, and changes in these barriers can vary across diseases and from patient to patient, occurring at the systemic, microenvironmental, and cellular levels. This makes it difficult to isolate and characterise these changes broadly. To design optimally engineered nanoparticles, it's essential to understand the biological barriers faced generally and on a patient-specific level.