Determination of droplet size of propofol fat emulsion injection / 中国药学杂志

ABSTRACT

OBJECTIVE: To establish a method to determine the droplet size of propofol fat emulison injection for quality control. METHODS: Coulter counting and light diffraction were employed respectively to determine the droplet size of Diprivan® and Lipuro®, and the two methods were compared for their advantages and disadvantages. The optimal determining condition was built through investigating the influence of concentration. Demulsification was carried out by adding electrolyte, then several parameters were measured. According to the results, the optimal condition and the key parameter for determination of the droplet size were established. RESULTS: The optimal concentrations for droplet size determination by coulter counting were 15 μg · mL-1 for Diprivan® and 6 μg · mL-1 for Lipuro®, respectively. Coulter counting method could not provide the whole size distritbution of the emulsion, but could monitor the large droplets in the injection. Additionally, the change of the quality of the emulsion could be monitored by measuring the portion of the droplets larger than 0.6 μm. Light diffraction could offer the whole size distribution and the mean size of the emulsion. But it was not sensitive to measure large droplets in trace amount. And the detection results could not reflect the change when the emulsion was destructed. CONCLUSION: The quality of propofol fat emulsion can be effectively controlled by determining the key parameters with coulter counting under reasonable conditions.