Fast Sensing of Hydrogen Cyanide (HCN) Vapors Using a Hand-Held Ion Mobility Spectrometer with Nonradioactive Ionization Source

• Main Authors: Victor Bocos-Bintintan, Ileana Andreea Ratiu
• Format: Article
• Language: English
• Published: MDPI AG 2021-07-01
• Series: Sensors
• Subjects: hydrogen cyanide (HCN); ion mobility spectrometry (IMS); trace detection; toxic industrial compounds (TICs); chemical warfare agents (CWAs)
• Online Access: https://www.mdpi.com/1424-8220/21/15/5045

Sensitive real-time detection of vapors produced by toxic industrial chemicals (TICs) always represents a stringent priority. Hydrogen cyanide (HCN) is definitely a TIC, being widely used in various industries and as an insecticide; it is a reactive, very flammable, and highly toxic compound that affects the central nervous system, cardiovascular system, eyes, nose, throat, and also has systemic effects. Moreover, HCN is considered a blood chemical warfare agent. This study was focused toward quick detection and quantification of HCN in air using time-of-flight ion mobility spectrometry (ToF IMS). Results obtained clearly indicate that IMS can rapidly detect HCN at sub-ppm_v levels in air. Ion mobility spectrometric response was obtained in the negative ion mode and presented one single distinct product ion, at reduced ion mobility K₀ of 2.38 cm² V⁻¹ s⁻¹. Our study demonstrated that by using a miniaturized commercial IMS system with nonradioactive ionization source model LCD-3.2E (Smiths Detection Ltd., London, UK), one can easily measure HCN at concentrations of 0.1 ppm_v (0.11 mg m⁻³) in negative ion mode, which is far below the OSHA PEL-TWA value of 10 ppm_v. Measurement range was from 0.1 to 10 ppm_v and the estimated limit of detection LoD was <i>ca</i>. 20 ppb_v (0.02 mg m⁻³).