Gas chromatography-mass spectrometry method for determination of β-propiolactone in human inactivated rabies vaccine and its hydrolysis analysis

A simple method was established for the determination of β-propiolactone (BPL) in human inactivated rabies vaccine by gas chromatography-mass spectrometry (GC-MS). The determination was performed on an Agilent HP-INNOWAX (30m × 0.32mm i.d., 0.25 μm) capillary column at the temperature of 80 °C. Electrospray ionization (ESI) was used by selective ion detection at m/z 42. The temperature for ESI source and inlet was set at 230 °C and 200 °C, respectively. Helium was used as the carrier gas at a flow rate of 25.1 mL/min. The total run time was 8 min. Acetonitrile and other components in the sample did not interfere with the determination of BPL. The results showed good linearity of BPL in the range of 0.50–10.01 μg/mL, with the limit of detection and the limit of quantification of 0.015 μg/mL and 0.050 μg/mL, respectively. Satisfactory precision was achieved for the current developed method. The method was applied to detect 6 batches of vaccine samples, and the results indicated that the target analyte BPL was present in three batches of unpurified samples, but was not detected in the purified samples, indicating the test samples were qualified. The established method was proved to be simple, versatile and sensitive, which can meet the requirements of quality control of BPL in human inactivated rabies vaccine.