The discipline of nanomedicine is in its development stage, and once developed, it can bring drastic changes in the arena of medicine through accurate targeting, better carrying capacity, and the fewest side effects. An important aspect that has an impact on the effectiveness of nanomedicine is the geometry of the nanoparticles. Nanoparticle geometry and size are critical in modulating the behaviour of nanoparticles in biosystems and, hence, cell uptake, biodistribution, and, in general, the therapeutic index. It becomes important to understand how these factors are affected by nanoparticle shape for the better development of nanomedicines. Thus, the article focuses on the concept of nanoparticle shape in nanomedicine and elaborates on the shapes listed in the first point, their behaviour concerning cells and tissue, and their potential for further development in medicine.
Understanding Nanoparticle Shapes
Nanoparticles can be prepared in different structures, such as spherical, rod, cube, and any format in the shape of stars, flowers, and so on. The physical and chemical attributes of each shape are different, as are the biological effects. For example, spherical nanoparticles are typically used to become ideal for synthesis, and their properties are clearly stated. However, non-spherical nanoparticles have revealed manipulated proficiency in particular applications because of the increased surface area as well as altered interactions with cells.
Spherical Nanoparticles
Among all types of nanoparticles applied in nanomedicine, spherical NPs are the most widespread due to their regular geometry, which provides controlled dispersion in bio environments. Due to their isotropic properties, optimal interaction with cellular membranes is achieved; therefore, they are used in drug delivery systems, imaging, and diagnosing. Yet, they can sometimes be restricted in what they can do compared to shapes of higher complexity.
Rod-Like Nanoparticles
Nanorods are elongated structures that offer a larger surface area-to-volume ratio relative to spherical nanoparticles. This increased surface area may prove useful in terms of cellular uptake as well as drug loading capacity. The optical properties of nanorods are also different from those of other types of nanoparticles, allowing for their use in photothermal therapies, diagnostic procedures, and other related uses. They are long-shaped, so they can have better penetration into tissues; this should be considered a plus for certain types of cancer.
Cubic and Polyhedral Nanoparticles
Among all the nanoparticles, cubic and polyhedral ones are preferable because of the presence of multiple facets with many binding sites for targeting moieties or drugs. These shapes can improve the stability and practical loading of the therapeutic agents. Also, their smooth edges and corners are likely to affect cellular uptake mechanisms, which in turn enhance the local delivery of therapeutic agents to certain cellular sub-compartments.