The kinetics of the degradation process is reported to be dependent largely on the concentration [6]. That is why we conducted a Anlotinib chemical structure further experiment to quantify this phenomenon. The stability of the etoposide solution in the disposable perfusion devices was studied in NaCl 0.9 % and in D5W at 600 mg/L. 2.3.4.1 Sampling and Analytical Pre-treatment After preparing the devices, a sample (S1) was tested at H0 in order to determine the initial concentration of the solution.

A second sample (S2) was tested at H24 to quantify the concentration in the device after 24 h. The samples were placed in a vial and then directly into the chromatographic system. A volume of 10 μL was injected. At H24, we drilled through the balloon drug reservoir via the shell of the device and recovered 100 mL of the solution that were then placed in two 50 mL-Falcon® tubes (F1 and F2). The contents of each tube were centrifuged for 5 min at 3,000 rpm; the supernatant was then eliminated to obtain the precipitate. To obtain the whole precipitate in the device,

the inside of the shell and of the balloon was rinsed twice with 10 mL of water using a syringe with a needle (L1 and L2). L1, L2 and the precipitate were mixed and centrifuged for 5 min at 3,000 rpm. After elimination of the supernatant, the precipitate was dissolved in 25 mL of methanol. Concentrations of etoposide methanolic solutions were determined by HPLC-UV in the conditions described above. Finally, the L1 and L2 samples were

analysed by injecting 10 μL into the chromatographic system. Etoposide concentrations were determined to evaluate selleck screening library the efficiency of the washing and thus the reliability of the precipitate recovery method. 3 Results 3.1 GNA12 Forced Degradation Study Exposition of etoposide solutions to studied conditions led to precipitation after 48 h for ambient and 33 °C storage conditions except for alkaline conditions, where coloration of solution was observed instead of a precipitation. Figure 3 shows results of the forced degradation study for 600-mg/L etoposide solutions in various dissolution media. Curve A shows the results of an Cediranib cost injection of etoposide solution diluted in NaCl 0.9 %; curve B shows the chromatogram resulting from the injection of a solution of etoposide diluted in NaOH 0.1 M injected right after dilution; curve C shows the chromatogram resulting from the injection of a solution of etoposide diluted in H2O2 10 % after 48 h of exposition; curve D shows the chromatogram resulting from the injection of a solution of etoposide diluted in HCL 0.1 M after 48 h of exposition; curve E shows the chromatogram resulting from the injection of a solution of etoposide diluted in NaOH 0.1 M after 48 h of exposition. Exposition to alkaline conditions yields a main degradation product eluted around 6.0 min, its content is increased after 48 h of exposition.