LIPOSOMES AS DRUG DELIVERY SYSTEM: EFFECT OF SUPERFICIAL CHARGE ON MARGINATION IN BLOOD FLOW

Aim of this work has been to analyze the effect of liposomes surface charge on their margination in blood flow in microcapillaries, i.e. the effect of the mechanism according to which particles migrate along vessel radius to the wall. To this scope high-speed imaging methods were used [4] and two kinds of tailored liposomal microstructures were designed and prepared by the duty cycle ultrasonic irradiation technique [5]. In particular large unilamellar vesicles (LUVs) with roughly 1 μm in size and -20 mV (neuter structure) and 50 mV (cationic structure) as zeta potential were produced (positive charge has been selected due to its suitable use in siRNA delivery). The microfluidic investigations were performed using fresh venous blood samples added with liposomes and a 50 μm diameter glass capillary in which the hydrodynamic conditions of human microcirculation were reproduced