cells in the medium were inoculated subcutaneously to mice in the amount of 2 × 106 cells per mouse at the right axilla, and the subcutaneous tumor growth in each mouse was monitored. The length and width of tumors were determined using a vernier caliper, and the tumor volume (V) was calculated as AZD6244 purchase V = d 2 × D / 2, where d and D are the shortest and the longest diameter of the tumor in millimeters, respectively . When the tumor volume reached approximately 50 mm3 (set as the 0 day), treatments were performed. The mice were randomly divided into three groups (each group has five mice, n = 5). The two formulations of paclitaxel, i.e., the drug-loaded CA-PLA-TPGS Fosbretabulin order nanoparticles and Taxol®,
were injected intra-tumorally at a single dose of 10 mg PTX/kg in PBS on days 0, 4, and 8. Physiological saline served as control. Mice were sacrificed by decapitation 12 days after treatment. The terminal tumor weight (mg) was determined and applied to evaluate the antitumor effects. Statistical methods All experiments were performed LGX818 supplier at least three times unless otherwise mentioned. Student’s t test statistical analysis was carried out with SPSS 17.0 software, with P < 0.05 considered to indicate a significant difference. Results and discussions Characterization of CA-PLA-TPGS copolymers In order to confirm the formation of the CA-PLA-TPGS copolymer, 1H NMR spectrum is recorded and is shown in Figure 1A. For the CA-functionalized star-shaped polymer CA-PLA-TPGS, the typical signals from CA moiety, TPGS
moiety, and LA monomer repeating units can be observed. 1H NMR (CDCl3): a (δ = 1.62 ppm, LA repeating unit: -CHCH 3), b (δ = 5.21 ppm, LA repeating unit: -CHCH3), c (δ = 3.65 ppm, TPGS repeating unit: -CH 2CH 2O-), d (δ = 0.50 to 2.40 ppm, CA moiety: -CH 2- and -CH-), e (δ = 4.38 ppm, terminal hydroxyl group of CA-PLA: -CHOH). Figure 1B shows the FTIR spectra of the CA-PLA-TPGS copolymer and TPGS. The carbonyl band of TPGS appears at 1,730 cm-1. For the CA-PLA-TPGS copolymer, the carbonyl band was shifted to 1,755 cm-1. Overlapping of the CH stretching band of PLA at 2,945 cm-1 and that of TPGS at 2,880 cm-1 was observed. The absorption band at 3,400 to 3,650 Megestrol Acetate cm-1 is attributed to the terminal hydroxyl group, and that at 1,050 to 1,250 cm-1 is due to the C-O stretching. The results confirmed that the CA-PLA-TPGS copolymer was synthesized by ring-opening polymerization. Figure 1 1 H NMR and FTIR spectra. (A) Typical 1H NMR spectrum of the CA-PLA-TPGS copolymer. (B) FTIR spectra of the CA-PLA-TPGS copolymer (black) and TPGS (blue). Nanoparticle fabrication PTX-loaded CA-PLA-TPGS nanoparticles were produced by a modified nanoprecipitation method, in which acetone was chosen as an acceptable solvent. Nanoprecipitation could provide a mild, facile, and low energy input method for the fabrication of polymeric nanoparticles .