Preparation and evaluation of stealth Tashinone IIA-loaded solid lipid nanoparticles: Influence of Poloxamer 188 coating on phagocytic uptake.

Stealth Tashinone IIA-loaded solid lipid nanoparticles (TA-SSLN) have been prepared by a nanoprecipitation/solvent diffusion method. Poloxamer 188 was used as a stealth agent. Nanoparticles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The profile of Tashinone IIA release from TA-SSLN was studied. Phagocytosis was evaluated by incubating TA-SSLN and non-stealth Tashinone IIA-loaded solid lipid nanoparticles (TA-NSLN) with murine macrophages. Human serum was added to evaluate opsonization of serum proteins. Rhodamine B was incorporated into nanoparticles as a fluorescent marker to observe and compare the phagocytic uptake of two kinds of nanopreticles. The results showed that TA-SSLN had an average diameter of (92.4 +/- 5.2) nm, zeta potential of (-20.4 +/- 1.3) mV, drug loading of (4.6 +/- 0.2)% and entrapment efficiency of (93.3 +/- 2.1)%. In vitro release experiment confirmed a sustained release of TA-SSLN and showed that the release of Tashinone IIA from TA-SSLN was in accordance with the Weibull equation. Phagocytosis studies showed significant differences between TA-SSLN and TA-NSLN and demonstrated that the Poloxamer 188 coating could decrease the macrophages uptake.