Perfluorocarbon emulsions have been considered as intravascular oxygen carriers (PFCOCs). However, deficient emulsion formulation and preparation, and insufficient experimental evaluation have prevented their clinical application. The purpose of this study is to optimize the formulation and preparation of PFCOCs, and to evaluate them in a model of normovolemic hemodilution in roedents. We also want to observe the efficiency and safety of these PFCOCs, using hemodynamical parameters and blood gases. Emulsions with two types of lecithins were elaborated varying the concentration of sodium chloride and glucose in order to change osmolarity and viscosity. Optimizing the previously used emulsions, a new methodology was developed. The effect of viscosity and osmolarity variation in the particle size of emulsions and its change with time was measured. Particle size stability has been attained up to 45 days. Emulsion osmolarity was modified using a multifactorial experimental design, in order to identify the osmolar contribution of the different components of the emulsion. Once identified, an osmolar curve was made in function of the different component osmolar contribution. A new generation of emulsions is being manufactured using a different type of lecithin at lower concentrations. The model of normovolemic hemodilution has been implemented. Initial results evidence an improvement of tissue oxygenation and arteriovenous difference when the PFC emulsion, recently manufactured by our research group, is used. Should the promisory results be confirmed, additional studies will be conducted in higher species.