Pharmacokinetics of doxorubicin incorporated in solid lipid nanospheres (SLN)

The pharmacokinetics of doxorubicin incorporated as ion-pair into solid lip id nanospheres (SLN) was compared with that of the commercial solution of t he drug. Male albino rats (Wistar-derived strain) were treated i.v. with eq uivalent doses (6 mg kg(-1)) of two different doxorubicin formulations: an aqueous dispersion of SLN carrying doxorubicin and a commercial doxorubicin solution (Adriablastina(R)). These formulations were injected, under gener al anaesthesia, through a cannula into the jugular vein and blood samples w ere collected at 1, 15, 30, 45, 60, 120 and 180 min after administration. A fter 180 min rats were killed and samples of liver, heart, lung, kidney, sp leen and brain were collected. Blood and tissue samples were analysed by a spectrofluorimetric method. The anthracycline concentration in the blood wa s markedly higher at each point times with the SLN than with the commercial solution. The drug concentration was also higher in the lung, spleen and b rain. SLN-treated rats showed a lower doxorubicin concentration in liver, h eart and kidney. The results showed that SLN increased the area under the c urve (0-180 min) of doxorubicin compared to conventional doxorubicin soluti on and led to a different body distribution profile. (C) 1999 Academic Pres s.