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Pharmaceutical analysis with portable spectrometers

Richard Crocombe of Crocombe Spectroscopic Consulting surveys the use of portable spectrometers in pharmaceutical manufacturing, with an emphasis on vibrational spectroscopy. Ideal and typical features of portable spectrometers are reviewed, alongside explanation of why device characteristics and sample presentation are critical to obtaining meaningful results.

Introduction

This article describes the use of portable spectrometers in pharmaceutical manufacturing with a focus on vibrational spectroscopy: mid‑infrared (MIR), near-infrared (NIR)1,2 and Raman. Over the last twenty years, the combination of advances in consumer electronics, telecommunications optics and photonics miniaturisation has driven the development of a wide variety of portable spectrometers, from Raman, NIR and mass spectrometry to nuclear magnetic resonance (NMR) relaxometry.3 In general, the applications of portable spectrometers are diverse, from safety and security to field geology,4 but they have particular importance in the pharmaceutical industry.

Table 1 lists the ideal and possible features of portable spectrometers, which feature in many instruments currently on the market. Although hyperspectral instruments (visible, NIR, Raman) are increasingly portable and available at lower costs, these are beyond the scope of this article.