Figure 2: (a) DLS analysis of SeNPs showing the size distribution of particles. Data indicates particles are polydisperse, with sizes ranging from 40 nm to 180 nm. (b) Zeta potential analysis showing the charge distribution on the SeNPs. The charge on the particles was found to be zero. (c) Comparison of the stability of SeNPs at 37°C after 5 h of incubation in different concentration of sodium bicarbonate buffer (pH 7. 4). Micro centrifuge tube (a), (b), and (c) are filled with biologically synthesized SeNPs having surface charge of -29 mV resuspended in bicarbonate buffer 0. 1 N, 0. 01 N and 0. 001 N respectively. Tube (d), (e), and (f) are filled with biologically synthesized SeNPs having surface charge of 0 mV resuspended in bicarbonate buffer 0. 1 N, 0. 01 N and 0. 001 N respectively. Particles having the surface charge settled due to agglomeration at 37°C.