Pulse purge thermal desorption ion mobility spectrometer for rapid and sensitive determination of intravenous anesthetic etomidate in blood

Rapid and sensitive determination of etomidate in blood is of great significance for anesthesiologists to adjust the depth of anesthesia, ensure the safety of operation and reduce the incidence of adverse reactions in patients, especially those with unstable hemodynamics. Herein, a positive photoionization ion mobility spectrometry method with acetone doped into the drift gas was developed, increasing the reaction efficiency of ion-molecule reactions and improving the detection sensitivity of etomidate in blood. Furthermore, the proposed injection method of pulse purge thermal desorption in bidirectional flow mode not only successfully improved the analysis performance of etomidate by increasing the effective injection amount of gaseous etomidate molecules, but also significantly reduced the impact of pressure fluctuation caused by the pulse on the quantitative accuracy. In view of the effective blood concentration range of etomidate from 1.25 to 3.75 ng μL−1, the proposed method with the quantitative range of 0.1–10 ng μL−1 was suitable for etomidate determination throughout the perioperative period. As a demonstration, the proposed method has been applied clinically to determine the concentration of etomidate in blood of patients undergoing tonsillectomy or nasal endoscopic functional sinus surgery. [Display omitted] •A positive ion mobility spectrometer for rapid and sensitive detection of etomidate in blood.•Pulse purge thermal desorption injection for increasing the effective injection amount of neutral gaseous etomidate molecules.•Accurate quantitative detection of etomidate with LOD reaching 0.017 ng μL−1.•Successful analysis of intraoperative blood etomidate in real clinical situations.