The Rise of Portable and Handheld Spectroscopy

In the past two decades, the field of analytical science has undergone a transformation reminiscent of the "Alice in Wonderland" miniaturization process.¹ Spectrometers used to be unwieldy bench instruments only suited for laboratories, where samples were brought to the instrument. However, thanks to technological innovation meeting the needs to users, spectrometers are routinely being miniaturized, down to the size of a computer mouse or cordless drills.¹ This technological leap is not just about size; it is about moving the laboratory to the point of measurement—whether that is a crime scene, soil sample, river bed, food production line, or a hospital ward.^1–3

In this Q&A article, we explore the current state and future of portable spectroscopy.

One of the most urgent uses of this technology is the opioid crisis. How is handheld spectroscopy being used to combat fentanyl?

Handheld Raman spectroscopy has become a frontline tool for law enforcement and first responders. Because fentanyl is lethal in ultra-trace amounts, identifying it safely in the field is critical.⁴ Standard Raman can identify bulk samples, but street drugs are often "cut" with other materials, leaving fentanyl at very low concentrations.⁴ To address this, instrument manufacturers like Metrohm have been using surface-enhanced Raman spectroscopy (SERS). SERS utilizes nanostructured substrates (often Ag or Au) to amplify signals, allowing the detection of trace amounts of analyte that would otherwise be undetectable.⁴ This allows for safe "presumptive" testing; for example, a suspected powder can be diluted and measured on a test strip, much like a diabetic test, keeping the examining officer safe from exposure.⁴

Beyond narcotics, how is portable technology addressing the issue of "food fraud"?

Food fraud is the intentional adulteration of products for financial gain. Sadly, it is currently a multi-billion-dollar problem.⁵ As a result, researchers and food manufacturers have utilized handheld Fourier transform infrared (FT-IR) spectrometers to detect adulterated products. FT-IR spectrometers are ideal for this type of application because they identify the unique "vibrational fingerprints" of molecules.⁵ Portable systems allow for "farm to fork" monitoring, speeding up the certification of incoming materials and detecting contaminants like melamine without the need for complex sample preparation.⁵ FT-IR is also able to detect diluted, substituted, falsified, misrepresented, or unsanitary product quality issues.

We often hear about X-ray fluorescence (XRF) in this context. How are these devices evolving in terms of usability and data management?

Handheld XRF has been a staple for analyzing metals and minerals for years. However, as of late, instrument manufacturers, such as Thermo Fisher Scientific with their XL5e series, have focused their efforts on making sure these handheld devices have improved connectivity and software integration.⁶ For example, this normally includes building in Wi-Fi and Bluetooth connectivity.⁶ Both these features have facilitated accelerated quality control. Wi-Fi, for instance, allows for the instant sharing of results to a PC or network for deeper expert analysis or consultation, while Bluetooth connects the device to accessories like external GPS units, barcode scanners, or portable printers.⁶

What technical breakthroughs have allowed these instruments to become so small without losing their "faculties"?

The miniaturization is driven by the closer coupling of components and advances in electronics, battery technology, and displays.^2,3 Specifically, moving from reflection gratings to transmission gratings has significantly improved the signal-to-noise ratio in smaller form factors.³ Additionally, the shift from fiber-coupled components to free-space optical coupling in "second-generation" devices helped reduce the physical footprint.³ We are now seeing "third-generation" devices that utilize smartphones as their data system, leading to spectrometers as small as 6 cm in length and weighing only 63 grams.³

Is there a practical limit to how small these devices can get?

Yes. There are two main obstacles, and they relate human interface and physics. For a standalone instrument, there is a practical minimum size defined by the need for a readable display and buttons that can be operated while wearing protective gloves.² From a physics standpoint, the ultimate limit is photon throughput.² A spectrometer must be able to collect enough scattered photons to produce a clear signal within a reasonable timeframe (usually seconds to a minute).² If the optics become too small, the measurement time becomes unmarketable.²

What does the future look like? Will spectroscopy become a part of our daily lives?

The market is projected to grow to over $4 billion by 2030, driven by the move toward wearable technology.² We are already seeing research into wearable near-infrared monitors for athletic performance and headbands for brain monitoring.² Low-cost multispectral sensors, which often cost less than $100, could soon be embedded in "smart" home appliances or even toilets.¹ Future "smart toilets" could use embedded sensors to analyze a user's excreta, providing real-time health and dietary guidance. Eventually, these sensors will likely be ubiquitous, residing in our pockets and even in our clothing.^1,2

References

1. Crocombe, R. Spectrometers in Wonderland: Shrinking, Shrinking, Shrinking. Spectrosc. Suppl. 2022, 37 (s11), 6–11. DOI: 10.56530/spectroscopy.Iz8466z5
2. Workman, Jr., J. Portable and Wearable Spectrometers in Our Future. Spectroscopy. Available at: https://www.spectroscopyonline.com/view/portable-and-wearable-spectrometers-in-our-future (accessed 2026-04-10).
3. Crocombe, R.; Kammrath, B.; Leary, P. E. Portable Raman Spectrometers: How Small Can They Get? Spectrosc. Suppl. 2023, 38 (s6), 32–40. DOI: 10.56530/spectroscopy.cn5172t4
4. Lavery, P. Handheld Raman to Fight Fentanyl—A Crucial New Use for an Established Tool. Spectroscopy. Available at: https://www.spectroscopyonline.com/view/handheld-raman-fight-fentanyl-crucial-new-use-established-tool (accessed 2026-04-10).
5. Lavery, P. Q&A: Portable FT-IR Empowers On-Site Food Quality Assurance. Spectroscopy. Available at: https://www.spectroscopyonline.com/view/transformative-solutions-portable-ftir-on-site-food-quality-assurance (accessed 2026-04-10).
6. Margeson, J.; Wetzel, W. How Will Handheld XRF Instrumentation Shape Field-Based Elemental Analysis? Spectroscopy. Available at: https://www.spectroscopyonline.com/view/how-will-handheld-xrf-instrumentation-shape-field-based-elemental-analysis- (accessed 2026-04-10).