Portable Pen-Probe Analyzer Based on Ion Mobility Spectrometry for in Situ Analysis of Volatile Organic Compounds Emanating from Surfaces and Wireless Transmission of the Acquired Spectra

Abstract

The analysis of volatile organic compounds (VOCs) normally involves sample collection, sample transfer to laboratory, sample preparation, and the chromatographic separation of analytes. However, in some cases, it is impractical or impossible to collect samples prior to the analysis, while the analysis time has to be minimized. Ion mobility spectrometry (IMS) is an ideal technique for a rapid in situ chemical analysis. Here, we present a portable cloud-integrated pen-probe analyzer based on IMS and demonstrate its applications in the analysis of VOCs emanating from surfaces. The user approaches the penprobe to a sampled surface and presses a button on the pen-probe. The analysis is then executed automatically. The VOCs are scavenged from the surface by a suction force and directed to a corona discharge atmospheric pressure chemical ionization source. The ions are separated in a drift tube according to their size and charge and then detected by a Faraday plate detector. The detector signal is amplified and digitized. The spectral data are deposited in the Internet cloud along with time and location data for further retrieval and processing. The platform incorporates a mobile Wi-Fi router for easy connectivity and a global positioning system module for geolocation. The prototype was developed using low-cost electronic modules (Arduino, Tinker Board S). It was further characterized using chemical standards. The limits of detection for pyrrolidine, 2,4-lutidine, and (−)-nicotine are 48.9, 2.30, and 416 nmol, respectively (amounts of substances placed on the sampling surface). The selected real specimens (nicotine patch, skin exposed to nicotine, fish sauce, and fried chicken) were also subjected to analysis yielding the characteristic ion mobility spectra.

Robotized Noncontact Open-Space Mapping of Volatile Organic Compounds Emanating from Solid Specimens

“…Here, the robotized PENVOC was coupled with MS; however, suction probes are also readily combined with other spectroscopic tools such as ion-mobility spectrometry ( e.g. , ref ). Thus, it is imaginable that the robotized PENVOC can be coupled with other spectrometers to provide different selectivities, while mapping VOCs.…”

Catalytic Oxygenation-Mediated Extraction as a Facile and Green Way to Analyze Volatile Solutes

“…Drift tube IMS is widely used for rapid profiling of samples containing VOCs ( e.g. , refs – ). Similar to the APCI-MS setup, in the case of APCI-IMS setup, the gas flow line downstream from valve 1 was connected to the inlet of the tritium APCI source (Figures E,F).…”

Remote monitoring of volatiles by ion mobility spectrometry with wireless data transmission and centralized data analysis

“…A prototype of a portable drift tube ion-mobility spectrometer—utilizing multiple low-cost electronic components—was developed previously. 3 The drift tube and the detector (Faraday plate) were fabricated based on the report by Reinecke and Clowers. 40 The system was powered by a lithium battery (24 V, 50 Ah; model no.…”

“…In our previous work, the atmospheric pressure chemical ionization (APCI) source was kept in an open-space holder. 3 However, the ionization efficiency was low due to the open-space layout of the ion source. In the present study, we re-designed the ion source holder (Fig.…”

“…Similar to the previous version of the mobile platform, 3 the current version took advantage of a mobile phone WiFi router to achieve Internet connectivity. Furthermore, a long-range (LoRa) radio frequency communication module (Lora RFM9X; Taiwan IoT Studio, Tainan City, Taiwan; LoRa1) was connected to the Arduino MCB (Arduino Due; Centenary Materials Company; MCB2) to achieve wireless data transmission in the absence of mobile phone network.…”