Engineering chemical detectors for outdoor use
From air quality on Earth to Space Odyssey!

Engineering chemical detectors for outdoor use
From air quality on Earth to Space Odyssey!

When the lab goes to the sample!

Chemical analysis is the practice that provides qualitative and quantitative information on the composition of matter. Industrial, pollution reduction and operational demands make extensive use of chemical analysis, for addressing quality control, process monitoring, security, safety and surveillance.

In most applications, there are no strict limitations regarding sample analysis time and, consequently, samples can be collected onsite, transferred to the lab where chemical analysis can take place without any time constraints. 

If the analytical demand is high in terms of time constraints, or a fast decision needs to be made based on the analysis results, then the bench-top (lab) chemical analysis has its limitations. Classical, bench-top analysis with field sampling, labelling, transferring to the lab, analytical sample preparation and, finally, chemical analysis needs to be replaced by alternative approaches.

Solutions must be found in order to efficiently and effectively cope with the application demands, on-site and on time. In such cases, Field Chemical Analysis needs to be applied. This is the solution whenever a need exists for spatial chemical analysis; e.g., when an area (air, water, soil) needs to be screened for hazardous compounds.

Field Chemical Analysis specializes in developing methods, procedures and technology for calibration, sampling and analyzing on-site and on time. It is applied for screening purposes or for getting near real-time chemical measurements (monitoring).

More specifically, Field Chemical Analysis is the practice of measuring, in space and time: 

  • the change in types of chemical compounds and
  • the concentration variations of chemical compounds

The vocabulary

The term “field” in Field Chemical Analysis has the meaning for space and/or time domains. Spatial measurements can be carried out in different directions, horizontally or vertically. Temporal measurements are generated by monitoring in fixed points (a point source, a stack) or when in motion and can be discrete, continuous or transient. Field screening is a type of Field Chemical Analysis which allows for fast sorting, separation or selection of samples.

Important

In the literature, the following definitions have also been reported for Field Chemical Analysis: “the analytical use of chemical sensors and procedures outside the traditional confines of a fixed laboratory and the practice of producing appropriate qualitative and/or quantitative information with analytical instruments that are operated at or near the sample collection location and which convert data to chemical information in a time frame that is consistent with near real-time applications”. Field Chemical Analysis has been alternatively referred to as “extra-laboratory analysis”, “on-site analysis”, “Field Analytical Chemistry” and “Fieldable Analytical Chemistry”.

However, there is an agreement that Field Chemical Analysis (or as named alternatively in the literature) has:

  • potentiality for on-site calibration of sensors/detectors/analyzers (field calibrator
  • a set of methods of analysis (analytical methods)
  • procedures (operational functions)
  • devices and systems (technology)

It is also agreed that it supports Detection, Identification, Monitoring (DIM) and surveillance for different chemical compounds. 

Field Chemical Analysis at operational level

Field Chemical Analysis is an integrated practice. It is enhanced through integration of multidisciplinary technologies; mixing different methods of chemical analysis with data processing and software. To ensure high performance and efficiency Field Chemical Analysis needs to be combined with information and communication technologies (ICT).

With the right mix of sampling units, chemical sensors, firmware, software, wireless communications and data bases, Field Chemical Analysis can be a valuable tool for decision makers.

Field Chemical Analysis can provide highly valued information required for:

  • Initiating emergency procedures
  • Acquiring data for fast decision making
  • Diagnosing health and safety issues
  • Continuous monitoring of industrial processes, environmental phenomena or events 
  • Identification of industrial process malfunctions and chemical accidents

Historical perspective

Field Chemical Analysis is maybe one of the oldest areas of chemical analysis. It was directly used by our primitive human ancestors for making decisions regarding their environment, food, threats and health. As a result, Field Chemical Analysis has evolved through the years.

In the following figure, representative historical and contemporary applications are presented.

Field Chemical Analysis: A panorama of applications
© 2021 T4i Engineering

Milestones of Field Chemical Analysis evolution are presented in the following figure.

Field Chemical Analysis: Milestones
© 2021 T4i Engineering

Historically, field analysis is documented as early as 500 BC by Theophrastus, a philosopher of classical times. It is described in his book “On Stones” in an excellent translation by Ohio University dated in 1956, as a test for gold identification and determination.

In the 1770 AD, the great chemist Antoine Lavoisier ran an experiment for measuring expired air.

In the 1940s, the development of a portable pH-meter was published as s “self-contained, portable pH-meter”.

Central chemical methods such as GC and Py-GC-MS were used in 70s for Field Chemical Analysis in NASA Viking and Soviet’s Venera in space programs. In the early 80s the development of e-nose and IMS as portable instruments were reported for Hazmat applications and coping with CBRN threats.

Later, in the early 90s, Field Chemical Analysis by speed platforms was demonstrated; roving electric van, helicopters and balloons were used.

In the turning of the century, developments in miniaturization, affect size and shape of on-site instruments and miniaturized versions of GC-IMS and GC-MS are made. In 2007, an IMS is reported on-board of a UAV, doing data transmission during flight. Further to the use in various space missions in Mars and other planets of our solar system, Field Chemical Analysis can be found today on board vehicles, both unmanned aerial (Chemical Detector on Board UAVs) and ground vehicles (UGVs).

What we at T4i engineering envision for Field Chemical Analysis

For addressing challenges in safety, security, as well as, in environmental, energy and space missions, Field Chemical Analysis needs to acquire a highly competitive technology with powerful chemical analytical competencies at its core, whilst embedding the best tools of the ICT world.

We believe that integration of 3D CAD-CAM together with multi-physics tools in the design of mechanical and pneumatic components and electronic boards can be efficiently combined with subtractive and additive manufacturing. This integration will lead to a new generation of chemical detectors and analyzers for field use; this will radically change the end-to-end design and manufacturing of field chemical detectors, analyzers and field calibrators in a revolutionary manner.

FemtoMachine: The T4i engineering field calibrator
© 2021 T4i Engineering

References

Reviews

  • Dalton T. Snyder, Christopher J. Pulliam, Zheng Ouyang and R. Graham Cooks, Miniature and Fieldable Mass Spectrometers: Recent Advances, Anal. Chem,  2016, 88, 1, 2-29
  • GA Eiceman, JA Stone, Ion Mobility spectrometer in national defense, Anal. Chem. 2004, 76, 21, 390 A–397 A
  • Edward B. Overton, H. P. Dharmasena, Ursula Ehrmann, Kenneth R. Carney, Trends and Advances in Portable Analytical Instrumentation, Field Analytical Chemistry and Technology 1(2):87–92, 1996
  • Philip A. Smith, David Koch, Gary L. Hook, Richard P. Erickson, Carmela R. Jackson Lepage, Haley D. M. Wyatt, Geoffrey Betsinger, Brian A. Eckenrode, Detection of gas-phase chemical warfare agents using field-portable gas chromatography–mass spectrometry systems: instrument and sampling strategy considerations, Trends in Analytical ChemistryVolume 23, Issue 4April 2004, Pages 296-306.
  • Yu.A. Zolotov, V.M. Ivanov, V.G. Amelin, Test methods for extra-laboratory analysis, Trends in Analytical Chemistry, vol. 21, no. 4, 2002
  • Joseph Wang, Portable electrochemical systems, Trends in Analytical Chemistry, vol. 21, no. 4, 2002, 226-232

Journals

  •  “Field Analytical Chemistry and Technology”, John Wiley and Sons, volumes 1-5, 1996-2001, Editor: Henk L.C. Meuzelaar

Conferences and Workshops

  • Gottlieb, J.; Hötzl, H.; Huck, K.; Niessner, R. (Eds.), “Field Screening Europe 1997 – Proceedings of the First International Conference on Strategies and Techniques for the Investigation and Monitoring of Contaminated Sites”, Karlsruhe, September 29-October 1, Kluwer Academic Publishers, 1997. 
  • Wolfgang Breh, Reinhard Niessner, Johannes Gottlieb, Heinz Hotzl, Frieder Kern, Tanja Liesch (Eds), “Field Screening Europe 2001 – Proceedings of the 2nd Second International Conference on Strategies and Techniques for the Investigation and Monitoring of Contaminated Sites, , Karlsruhe, May 14 – May 16, Kluwer Academic Publishers, 2001.
  • “On-site Analysis. The Lab comes to the Field” International conferences (from 1992 until today in U.S.A), (Infoscience Services, Inc., IL)
  • Specialist Workshop on Field-Portable Chromatography and Spectrometry,  Snowbird (Utah, USA), June 1996.

For more information, contact us at info@t4ieng.com