Juan Sebastian Totero Gongora
Posters-Accepted Abstracts: Biol Syst Open Access
While optics has historically been mainly used for imaging applications, light has now become a tool of manipulation and direct interaction with biological samples. It is well known that when light impinges on an object, it exerts a small pressure on it known as optical force. An immediate application of optical forces is found in optical tweezers, which in biology are usually employed as a non-invasive technique to immobilize cellular organisms for imaging purposes. These techniques, including more pioneering ideas such as, e.g., cell optical sorting and in-vivo manipulation, require a precise understanding on how the optical pressure affects biological organisms. This calls for the development of precise numerical methods, whose development will be crucial for applications of the aforementioned techniques. In this respect, ab-initio techniques represent a very important tool that can provide quantitative answers to the problem. By employing a series of massively parallel FDTD simulations, we study how optical forces act on biological matter. As a representative case study, we here consider deformed Red Blood Cells (RBC) illuminated by a monochromatic plane wave. We consider typical deformations arising due to the presence of a disease such as malaria. Realistic parameters for the geometry and the refractive index are then taken from published experiments. In our theoretical campaign, we study the dependence of the optical force on the particle shape and the incident wavelength. We show that optical forces change appreciably with the deformation, with amplitude variation in the pN range for RBCs affected by disease.
