Agilent 8700 LDIR Chemical Imaging System

Significance of the Topic

The Agilent 8700 LDIR chemical imaging system addresses critical needs in compositional analysis by combining high spatial resolution, rapid data acquisition, and ease of use. It leverages quantum cascade laser (QCL) technology and automated optics to produce detailed chemical maps of surfaces, significantly reducing analysis time across pharmaceuticals, materials science, and life science research.

Study Objectives and Overview

This application note introduces the 8700 LDIR approach to chemical imaging and spectral analysis. It aims to demonstrate how integrating QCL-based infrared illumination with intuitive software and automated sample handling can accelerate routine and challenging analyses. Key objectives include validating imaging speed, resolution, and analytical robustness for diverse sample types.

Methodology and Instrumentation

The 8700 LDIR operates in two modes: reflectance and attenuated total reflectance (ATR). A flip mirror and automated beam path switching enable seamless transitions between modes. Sample movement is fully motorized, allowing large-area surveys and high-magnification scans without manual optics changes.

Key instrumentation components:

• Quantum Cascade Laser: tunable mid-IR source for selective excitation of molecular vibrations.
• Fast Scanning Objective and Mirror: raster-scans the focused beam over the sample surface.
• Thermoelectrically Cooled MCT Detector: single-element detector eliminates coherence artifacts for clean spectra.
• Fixed ATR Objective: enables high-resolution contact imaging with pixel sizes down to 0.1 µm.
• Visible Cameras: large-field camera for overview and microscope-grade optics for detail imaging.
• Agilent Clarity Software: fully automated method creation, spectral library matching, and report generation.
• Agilent Sample Planer: maintenance-free device to prepare flat sample surfaces up to 25 × 50 mm.

Main Results and Discussion

Performance trials illustrate that whole pharmaceutical tablets (11–13 mm dia.) can be imaged at 10 µm pixel resolution in under an hour. Detailed chemical maps reveal API distribution, polymorphic forms (e.g., carbamazepine forms I and III), and excipient localization. In life-science applications, 12 mm × 7 mm tissue sections were mapped at 1 µm pixel size within 60 minutes, resolving lipid domains in mouse brain slices. Material science case studies demonstrated layer identification in multilayer laminates with thickness down to ~2.6 µm, streamlining failure analysis and quality control.

Benefits and Practical Applications

The 8700 LDIR system offers numerous practical advantages:

• Automated, load-and-go operation minimizes training requirements.
• High throughput: surveys large areas then zooms into regions of interest without hardware swaps.
• Versatile sample compatibility: tablets, thin films, tissues, polymers, fibers.
• Quantitative and qualitative analysis: semi-quantitative composition estimates and library-based identification of unknowns.
• Lower operating cost: no liquid nitrogen needed for cooling.

Future Trends and Potential Applications

Emerging opportunities include coupling LDIR imaging with artificial intelligence for automated feature recognition, in-line process monitoring in manufacturing, and expanding spectral libraries with machine-learning classification. Integrating microfluidic sample handling and robotic sample loading could further boost throughput, while deeper UV-IR fusion imaging may open new insights in multimodal analysis.

Conclusion

The Agilent 8700 LDIR chemical imaging system delivers a transformative workflow for surface compositional analysis. By marrying QCL illumination, automated optics, and user-friendly software, it empowers researchers and technicians to generate high-definition chemical images rapidly and reliably, accelerating decision-making in R&D and QA/QC.

Reference

Agilent Technologies, "Agilent 8700 LDIR Chemical Imaging System", Application Note 5994-0275EN, May 2019.