In this study, it is aimed to filter nano-sized particles using light radiation pressure explicitly scattering and gradient forces. The light wave exerts momentum when encounters to the particles inside a solution. This momentum provides pulling force towards the high-intensity point as a result of gradient force and thrust in the direction of propagation resulting from scattering force. By controlling these two forces, the particles which have dissimilar properties can be moved to distinct directions. In this way, we have experimentally shown that two different particles can be separated from one another. It has been shown mathematically that separation of two particles based on size, material properties and geometry using radiation forces. Size-based particle filtration was performed with experimental studies on particles of different sizes. A threshold dimension value was assumed between 100 nm and 200 nm so that these particles could be separated from each other, and a design has been developed such that smaller particles are attracted towards the high-intensity point of the light with gradient force effect and larger particles are thrust in the direction of light propagation with scattering force. This setup was tested for silica particles of size 87 nm, 100 nm, 120 nm, 200 nm and 340 nm. Particles smaller than this threshold value were accumulated around the high-intensity region of light, while the larger ones continued to flow in the liquid. It has been experimentally shown that the nearest 120 nm and 200 nm particles were separated from each other. This study shows that particles with a difference of 80 nm in size can be filtered using radiation forces. Finally, blood samples were used in experimental studies. It is shown that the thrombocyte, lymphocyte and erythrocyte cells contained in the blood can be separated from each other using radiation forces.