Therefore, the drug was released incompletely from the NPs in 48 h. Thus, PTX-MPEG-PLA NPs are promising in the expansion of dosing range of chemotherapeutic drugs and rendering patients safe cancer therapy. Additionally, it was interesting to note that the cell viability in PTX-MPEG-PLA NPs was higher than that in PTX-PLA NPs at a series of increasing concentrations (2.5, 10, 20, and 40 μg/mL). This result can most likely be attributed to the drug release rate of the PTX-MPEG-PLA NPs being higher than that of the PTX-PLA NPs. Figure 7 In vitro cell viability assays GSK1120212 for growth inhibition effect after 48

h ( n  = 6). Conclusions In our previous study, a simple but successful method was developed to obtain PTX-MPEG-PLA NPs with appropriate formulation characteristics including small particle size, narrow particle size distribution,

high zeta potential, satisfactory drug encapsulation efficiency, and appreciable drug-loaded content. The PTX-MPEG-PLA NPs presented a faster drug release rate but minor burst release as well as a higher cell cytotoxicity Capmatinib in vivo compared to the PTX-loaded PLA NPs. A further study on the in vivo pharmacokinetics and antitumor effects of PTX-MPEG-PLA NPs is currently in progress. Acknowledgements This work was funded by the National Natural Science Foundation of China (grant nos. 81000660 and 31271071) and Xiamen Science and Technology Project (XMU-MP-1 3502Z20123001 and 3502Z20114007). References 1. Peer D, Karp JM, Hong S, Farokhzad OC, Margalit R, Langer R: Nanocarriers as an emerging platform for cancer therapy. Nat Nanotechnol 2007, 2:751–760.CrossRef 2. Petros RA, DeSimone JM: Strategies in the design of nanoparticles for therapeutic applications. Nat Rev Drug Discovery 2010, 9:615–627.CrossRef 3. Adair JH, Parette MP, Altinoglu EI, Kester M: Nanoparticulate 4-Aminobutyrate aminotransferase alternatives for drug delivery. ACS Nano 2010, 4:4967–4970.CrossRef 4. Kievit FM, Zhang M: Cancer nanotheranostics: improving imaging and therapy by targeted delivery

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