The innovative research described in this article is based on perfluorocarbon (PFC) nanodroplets. PFCs are organofluorine compounds that contain only carbon and fluorine and, in this research, they are the blank nanoparticle in a double-layer emulsion format (water-in-PFC-in-water) without any surface modification nor entrapped material. ‘More specifically, PFC nanodroplets consist of three layers: a carboxylic poly (ethylene oxide)-block-poly(propylene oxide)-block-poly(ethy1ene oxide) (i.e., PEO-PPO-PEO block copolymer) as the outer layer material; a polyethoxylated fluorosurfactant as the inner layer material; and a perfluorooctyl bromide (PFOB) as the PFC material located between these two layers,’ explains Lee. ‘Tumour-target photosensitizer-anticancer drug-encapsulated PFC nanodroplet with double emulsion format is an ideal, effective, and clinically applicable drug carrier,’ he says. ‘The polymers used for both inner and outer layers are biocompatible, and the PFOB, a fluorine-substituted derivative of hydrocarbons, is a well-known robust oxygen transporter that is widely used as a contrast agent in MRI, CT and sonography applications.