Colloidal and optical stability of PEG-capped and phospholipid-encapsulated semiconducting polymer nanospheres in different aqueous media.

Aqueous dispersions of fluorescent semiconducting polymer nanospheres (SPNs) have been synthesised by two methods; miniemulsion and micellar encapsulation. The colloidal and optical stability of SPNs synthesised by these two methods has been compared in order to assess the potential of these fluorescent nanoparticles for use in biological applications. The SPNs were dispersed in water, phosphate buffer solution (PBS) and bovine serum albumin (BSA). The optical stability was studied by absorption and emission spectroscopy, and the colloidal stability was studied by dynamic light scattering (DLS) over a one month period. The results indicate that the micelle-encapsulated SPNs exhibit favourable optical and colloidal stability, and seem promising for use in biological sciences.