Compatibility and Stability of Cipepofol (Ciprofol) and Etomidate Mixture for Intravenous Anesthesia

To evaluate the physical and chemical compatibility and stability of a cipepofol (ciprofol) and etomidate (EC) mixture for intravenous anesthesia and assess the physiochemical stability of the drugs during co-administration through the same intravenous line.

High-performance liquid chromatography and other analytical techniques were employed to investigate the stability of the EC mixture. The mixture was prepared and stored at 4°C, 25°C, or 37°C for 24 h, and its appearance, pH, osmotic pressure, particle size, zeta potential, drug content, and related substances were evaluated at 0, 1, 3, 6, 12, and 24 h.

The EC mixture maintained physical stability, with no significant changes in appearance, pH (fluctuation, ≤0.07 units), osmotic pressure (relative standard deviation [RSD] < 2.0%), or particle size observed over 24 h. Zeta potential remained within acceptable limits (ranging from -40 to -30 mV), indicating good colloidal stability. Chemically, drug content remained at ≥99.9% of the initial level (RSD < 1.2%), and impurity levels stayed within the specified limits (maximum single impurity ≤ 0.13%, total impurities ≤ 0.37%).

The findings suggest that the EC mixture was physically and chemically compatible and stable for up to 24 h at various temperatures, making this regimen a potentially safe and effective option for intravenous anesthesia. This finding is significant for improving patient comfort and reducing adverse drug reactions during anesthesia induction and maintenance.