Fourier-transform infrared spectroscopy (FTIR) is one of the most common analytical techniques utilized in laboratories today, finding use in nearly all industries and functions. All IR spectroscopy works on a principle of molecular absorption. First, IR light is passed through a sample. Molecules absorb this light at different, discrete energies, depending on the molecular structure. This energy causes molecular bonds to vibrate, with different molecular functional groups vibrating at different frequencies. Since light is absorbed at different frequencies, this information can be translated into an IR spectrum, which gives users useful information about the molecular makeup of the sample being analyzed. IR spectroscopy was first developed in the 1950s. A number of developments, such as the use of the Michelson interferometer and computers able to perform FT, allowed for the creation of FTIR with improved speed and signal-to-noise ratio.

Many modern IR spectroscopy instruments utilize attenuated total reflection (ATR), allowing for little to no sample preparation. Using ATR, a beam of IR light passes through a crystal, which can be diamond, silicon or zinc-selenium. Within the crystal, the IR beam undergoes internal reflection that creates a wave of light that extends a few microns beyond the surface of the crystal. This light is absorbed by a sample placed on top of the crystal and is then interpreted to give an IR spectra. The development of ATR advanced FTIR even further, helping to create modern handheld FTIR instruments.

Handheld FTIR instruments are a relatively recent development, having been around for about a decade, and giving users more versatility in where and how to analyze samples. It opened the door to numerous applications that would be otherwise difficult or cumbersome for benchtop instruments. Functionally, handheld FTIR instruments are practically identical to their benchtop counterparts, but rely on smaller components, more rugged design and ease of use for a variety of environments.

Many of the applications for handheld FTIR instruments would be difficult to perform in a traditional lab setting. For example, one major application for these handheld instruments is to analyze metals, polymers and composites directly, which is useful in the aerospace and automotive industry. Combined with large spectral databases, handheld FTIR is used for security and safety purposes to quickly detect unknown narcotics, explosives and other chemicals. Industries where traditional benchtop FTIR instruments are used also employ handheld instruments. The pharmaceutical and chemical industries use these instruments to check raw materials, quickly analyze product intermediates during process development and to test finished products. Other applications well suited for the technology’s field use are found in the metals and mining, agriculture and food, and paints and coatings industries.

There are a few vendors that produce handheld FTIR instruments, but Agilent Technologies, Smiths Detection and Thermo Fisher Scientific are the three largest. Smiths Detection and Thermo Fisher produce instruments like the HazMatID Elite and the Gemini Analyzer, respectively, which are each geared towards safety and security applications. Agilent, with its 4300 FTIR Analyzer, has been a leading vendor for handheld FTIR since its acquisition of A2 Technologies in 2011 (see IBO 1/31/11).

The total handheld FTIR market was just under $65 million in 2018. Growth is expected to be in the mid- to high single digits, driven by their use in growing pharmaceutical, aerospace and automotive, and government testing applications.

Handheld FTIR at a Glance:

Largest Markets

• Government
• Polymers
• Chemicals

Leading Suppliers

• Smiths Detection
• Thermo Fisher Scientific
• Agilent Technologies

Instrument Cost

• $50,000–$100,000