NEAFS: Portable and Handheld FTIR

Importance of the Topic

Portable and handheld FTIR brings laboratory‐grade infrared spectroscopy directly into the field, offering rapid, non‐destructive identification of unknown materials. In forensic, environmental and industrial settings this capability accelerates decision making, reduces the evidence chain and supports real‐time threat assessment.

Objectives and Study Overview

This article reviews three Agilent at‐site FTIR systems (4300 Handheld, 4500 Portable, Cary 630 with SurveyIR microscope), illustrates analytical workflows for illicit drug screening, polymer additive quantitation and forensic casework, and demonstrates performance benchmarks for field deployment.

Methodology

Infrared spectroscopy measures unique vibrational frequencies of molecular functional groups to generate a spectral fingerprint. Sampling modes include attenuated total reflection (ATR), diffuse or specular reflection and transmission. Built‐in spectral libraries support automated qualitative searches and quantitative calibrations. Spectral subtraction and multivariate models enable mixture deconvolution and percent composition determinations.

Instrumentation Used

• 4300 Handheld FTIR: 2.2 kg, internal PC, hot‐swap batteries, multiple ATR and reflectance interfaces.
• 4500 Portable FTIR: 6.8 kg, internal battery, USB link to tablet, dedicated ATR accessory with diamond sensor.
• Cary 630 with SurveyIR microscope: video imaging, 5 MP camera, 1900 µm field of view, ATR or transmission sampling masks.

Main Results and Discussion

• Illicit Drug Identification: Street drug spectra matched against a forensic library, achieving rapid identification of cocaine, mixtures and adulterants using quality indices and residual spectral searching.
• Phthalate Quantitation in PVC: Mobile FTIR screening model calibrated low (0–3 %) and high (3–30 %) phthalate ranges with R2>0.99 and LOQ of 0.1 %. Analysis of a toy doll confirmed absence of regulated phthalates.
• Forensic Case Studies: Accident residue on a motorcycle pillion case was identified as carbon‐filled polypropylene and paint transfer by diffuse reflectance FTIR. Automated cocaine screening in seized samples provided probabilistic reporting based on peak combinations.
• Microspectroscopy Applications: SurveyIR accessory enabled analysis of fibers, paint chips and small particles under reflection, transmission and ATR modes, with rapid collection times and high spatial resolution.

Benefits and Practical Applications

At‐site FTIR systems deliver fast, reliable screening with minimal sample preparation, support chain of custody, reduce laboratory backlogs and empower field operatives in law enforcement, border control, QA/QC, environmental monitoring and decontamination verification.

Future Trends and Potential Uses

Anticipated developments include expanded libraries and chemometric models for emerging contaminants, integration with AI for automated interpretation, miniaturization of optics, broader adoption in consumer safety and regulatory compliance (e.g. RoHS expansion), and enhanced connectivity for remote reporting.

Conclusion

Portable and handheld FTIR technologies unify laboratory‐grade analysis with field portability, delivering versatile tools for rapid chemical identification and quantitation. Their proven utility in forensic investigations and industrial screening underscores a growing role in real‐time decision making across diverse disciplines.