Miniaturization of handheld vibrational spectrometers is recently undergoing a rapid development and market research companies predict this instrumentation sector a bright future primarily based on its on-site and in-the-field applications, its easy implementation for industrial process control and its private use by non-experts.
In a short introduction the basic principles of the three vibrational spectroscopic techniques (Raman, mid-infrared (MIR) and near-infrared (NIR)) will be compared and from the summary of miniaturization for the three techniques a lucid explanation for the apparent advantages of handheld near-infrared spectrometers can be drawn. Thus progress in miniaturization and level of prize are the clear benefits of NIR and the reason why Raman and MIR spectroscopy are limited only to industrial, institutional and first-responder customers.
Contrary to the exaggerated claims of several direct-to-consumer companies that advertise their “NIR scanners” with “cloud evaluation of big data”, this tutorial will provide an overview on the realistic application potential of these handheld instruments for a broad range of materials (food, pharmaceuticals, textiles, polymers, etc.) and will also point out where the authors believe handheld NIR spectroscopy can offer a better analytical alternative than current methods.
1. Short introduction to the basic principles of Raman, MIR and NIR spectroscopy
2. Historic overview of miniaturization in vibrational spectroscopy
3. Building principles of state-of-the-art handheld NIR spectrometers
4. Discussion of qualitative and quantitative application examples of handheld NIR spectrometers (e.g. authentication and quality control of food, pharmaceuticals, textiles, and polymers; analysis of geological samples and total petroleum hydrocarbons (TPH) in soil)
laboratory managers, analytical chemists, technicians, and graduate students