Nanoparticles have been widely applied in diagnosis and therapy due to the high loading of insoluble drug, increased target accumulation and interaction with biological tissues. Recently, severe side effects of nanoparticles have been reported, but the underlying mechanism remains largely unknown. In our study, we aim to understand the safety of paclitaxel （PTX） loaded bovine albumin nanoparticles （BNPs） and active targeted PTX loaded BNPs to normal vital organ or tissue in vivo. The anti-human epidermal growth factor receptor 2 （HER2/neu） peptide mimetic （AHNP） was covalent bound to surface of BNPs （AHNP-BNPs） to exert selected delivery to HER2＋ cells. In HER2＋ tumor xenographs, saline （control）, PTX traditional formula （medium of Cremophor EL-ethanol）, BNPs, and AHNP-BNPs were administrated to evaluate the toxicity. There is no severe neutropenia or anemia with treatment of BNPs and AHNP-BNPs compared with traditional PTX injection. We also evaluated their damage on normal organs, including liver, kidney, spleen, lung and heart to fully estimate the safety of AHNP-BNPs and BNPs delivery systems. We observed similar toxicity in liver and lung in mice treated with BNPs or PTX injection, but decreased liver damage in mice treated with AHNP-BNPs. Further studies are rcouired to confirm our conclusion.
