Perfluorocarbon-loaded micro and nanosystems for medical imaging: A state of the art

Perfluorocarbons (PFCs) are fluorinated compounds widely used in the past as oxygen carriers. They have been the focus of research as contrast agents for ultrasonography and fluorine magnetic resonance imaging (MRI). For ultrasonography, most contrast agents use gaseous PFCs and some are approved for clinical use. Liquid PFCs, however, are being studied for the past decade due to their improved stability under ultrasound waves. For fluorine MM, liquid PFCs are preferred due to their higher fluorine concentration, but for the moment no product is on the market yet. For both these imaging modalities, a large body of formulation is needed to allow safe PFC injection in the bloodstream. In this review, we will focus on PFC encapsulation into micro and nanosystems for medical imaging purposes, from research to the clinics. (C) 2014 Elsevier B.V. All rights reserved.