Rapid Screening of Trace Volatile and Nonvolatile Illegal Drugs by Miniature Ion Trap Mass Spectrometry: Synchronized Flash-Thermal-Desorption Purging and Ion Injection.

The increasing demand for rapid and sensitive roadside identification of trace illegal drugs drives the development of high-performance miniature mass spectrometric instrumentation and methodology. Here, we report a synchronized flash-thermal-desorption purging and ion injection (SFTDPI) method to increase the sensitive and rapid screening of volatile and nonvolatile illegal drugs for miniature ion trap mass spectrometry (ITMS). The flash-thermal desorption could reach 290 °C in 2.5 s, which could achieve efficient vaporization of nonvolatile noscapine with boiling point at 565 °C. ITMS using discontinuous atmospheric pressure interface (DAPI) has an ion utilization ratio of less than 1%, the synchronized purging for flash-thermal desorption and ion injection with DAPI could accurately control the time interval along with the desorption, gas purging, ionization and ion injection, and the sample utilization ratio increases more than five times. The miniature SFTDPI-ITMS presents good performance: (1) more than 60 times improvement in sensitivity was achieved compared to the previously reported thermal-desorption acetone-assisted photoionization ion trap mass spectrometer for nonvolatile drugs, and the minimum detectable quantity reaches 50 pg for fentanyl. (2) Ten kinds of mixing drugs with boiling point difference of 300 °C can be simultaneously identified within 3 s under a single analysis. SFTDPI-ITMS was deployed at the roadside checkpoint of Sino-Burmese border; fentanyl in the captured encapsulated powder and the suspected opiate had been successfully identified.