Deionized water was decarbonated by
boiling before its use in all of the applications. Synthesis of etoposide-loaded calcium carbonate nanospheres All the experiments were prepared at room temperature. Etoposide-loaded calcium carbonate nanospheres were www.selleckchem.com/products/elafibranor.html synthesized by mixing calcium chloride and sodium carbonate aqueous solution in the presence of ethanol, citric acid, and etoposide. Etoposide (0.2 g) and 10 mL CaCl2 (0.1 M) were dissolved in 60 mL mixed solvent of ethanol and deionized water (volume ratio = 1:2), marked as solution A. Na2CO3 (0.02 g) and 10 mL of Na2CO3 (0.1 M) were dissolved in 60 mL mixed solvent of ethanol and deionized water (volume ratio = 1:2), marked as solution B. Solution B was added dropwise to the vigorously stirred solution A. With the reaction proceeding, the milky white precipitation was obtained after 72 h at room temperature. The precipitation was washed thrice with mixed solvent of ethanol and deionized water (volume ratio = 1:2) and dried using vacuum freeze drier. The blank carrier CCNSs were prepared without the addition of etoposide, and other experimental parameters were similar to the ECCNSs
sample. Characterization The morphology of the ECCNSs was viewed by field-emission scanning electron microscopy (Hitachi S4800, Chiyoda-ku, Japan) selleckchem at an acceleration voltage of 1 to 5 kV and a JEOL 1230 transmission electron micrograph (TEM, Akishima-shi, Japan) at an acceleration voltage of 200 kV. Brunauer-Emmett-Teller (BET) surface area and pore distribution of the CaCO3 products
were determined from N2 adsorption-desorption isotherms using a Micromeritics TriStar 3000 system (OICR-9429 solubility dmso Norcross, GA, USA). The zeta potential distribution of nanoparticles Oxymatrine was analyzed by Nano ZS, Malvern Instruments Ltd., Southborough, MA, USA. Fourier transform infrared measurement was recorded on a Bruker Vector 22 spectrophotometer (Madison, WI, USA) in the range of 4,000 to 500 cm−1 using the standard KBr disk method (sample/KBr = 1/100). UV–vis spectra were measured on a CARY50 spectrophotometer (Varian, Victoria, Australia). The crystallographic structure of the solid samples was recorded using an X-ray diffraction (XRD, Bruker D8) with Cu Kα radiation (λ = 0.154056 nm) (Karlsruhe, Germany), using a voltage of 40 kV, a current of 40 mA, and a scanning rate of 0.02°/s, in 2θ ranges from 10° to 70°. The average particle size (z-average size) and size distribution were measured by photon correlation spectroscopy (LS230 Beckman Coulter, Fullerton, CA, USA) under a fixed angle of 90° in disposable polystyrene cuvettes at 25°C. Sedimentation study in RPMI-1640 medium Etoposide (5 mg) was placed in a centrifugal tube of 15 mL and resuspended with 10 mL RPMI-1640 medium supplemented with 10% fetal bovine serum and 1% penicillin-streptomycin solution.