Optimized analysis for oils, liquids, syrups and pastes

Significance of the topic

Rapid, reliable analysis of viscous and liquid materials such as oils, syrups, pastes and lubricants is essential across food, petrochemical, biodiesel and quality assurance laboratories. Analytical techniques that minimize sample handling risks, provide reproducible effective pathlengths for quantitative work, and deliver operator-friendly workflows reduce turnaround time and error, improving process control and regulatory compliance. Fourier-transform infrared (FTIR) spectroscopy with an optimized attenuated total reflectance accessory addresses these needs by enabling direct, robust measurement of challenging matrices without extensive sample preparation.

Objectives and overview

This document summarizes the capabilities and practical advantages of the Thermo Scientific Nicolet Summit OA FTIR Spectrometer, a purpose-built analyzer for viscous and liquid samples. The primary objectives are to describe the instrument and software features that enable rapid qualitative and quantitative analysis, to explain the analytical benefits of an integrated multi-bounce HATR accessory, and to outline typical application areas where the system improves QA/QC workflows and method reproducibility.

Methodology and analytical approach

The Summit OA combines FTIR spectroscopy with a horizontal zinc selenide (ZnSe) trough attenuated total reflectance (HATR) accessory designed for multi-reflection sampling. Key methodological elements include:

• Multi-bounce HATR geometry producing multiple internal reflections to increase effective absorbance and sensitivity compared with single-bounce ATR.
• Lower angle of incidence in the trough design, which extends the evanescent field interaction and yields greater signal for weak absorbers.
• Constant and reproducible effective pathlength because the sample rests in a defined trough over a pinned ZnSe crystal plate, improving quantitative precision.
• Integrated sample containment and leakproof cover to limit the risk of spills damaging optics or electronics during routine handling of viscous or liquid samples.
• Software-driven workflows (OMNIC Paradigm) that separate roles and simplify operations: touchscreen click-and-go, desktop mode for method creation and spectral processing, and operator mode for locked-down workflows.

These design choices reduce sample preparation, increase throughput, and support both qualitative identification and quantitative calibrations using multivariate tools when needed.

Instrument features and used instrumentation

The instrument integrates several hardware and software components optimized for viscous/liquid analysis:

• Thermo Scientific Nicolet Summit OA FTIR spectrometer with LightDrive Optical Engine providing high-performance, stable data acquisition.
• Integrated horizontal ZnSe trough HATR accessory (40-degree trough geometry) with multi-reflection configuration and user-replaceable, pinned ZnSe trough plate.
• Built-in Windows 10 computer; external monitor, keyboard and mouse are required for operation.
• OMNIC Paradigm software suite offering three operating modes (Touchscreen, Desktop, Operator) and seamless linkage to TQ Analyst multivariate analysis for quantitative modelling.
• Instrument status LightBar LED for rapid visual assessment and a smooth, leakproof cover to minimize spill risk.

The LightDrive engine is backed by a 10-year warranty on the interferometer, laser and source, emphasizing long-term reliability for routine QA/QC environments.

Main results and discussion

The integrated multi-reflection HATR approach significantly enhances sensitivity for liquid and viscous samples. Comparative data reported for single-bounce versus multi-bounce configurations indicate an approximately eightfold increase in apparent absorbance for many liquid bands, owing to the cumulative effect of multiple internal reflections and a lower incidence angle. This yields improved detection limits and greater precision for both qualitative fingerprinting and quantitative assays.

The fixed trough geometry delivers a reproducible effective pathlength, a critical parameter for reliable quantitative work and for building transferable calibrations. The pinned, user-replaceable ZnSe plate maintains optical alignment and simplifies routine maintenance without disturbing the instrument calibration.

OMNIC Paradigm simplifies deployment across different user skill levels. Operators can run standardized workflows via touchscreen mode with minimal training, while analysts can build and refine calibrations and spectral processing in desktop mode. Password-protected operator packages allow labs to enforce method control and traceability across shifts and sites.

Typical applications highlighted include snack food oil quality control, in-service lubricant condition monitoring, FAME (biodiesel) content measurement in fuel blends, and tailored customer-specific tests. Conformance to industry standards such as ASTM methods (examples cited include D7418, E2412, D7371) is supported through configurable workflows and multivariate analysis capabilities.

Benefits and practical applications

• Fast, low-preparation analysis of viscous and liquid matrices reduces laboratory turnaround time and operator exposure to samples.
• Enhanced sensitivity from multi-bounce HATR supports detection of minor components and low-level contaminants in oils and fuels.
• Reproducible effective pathlength and pinned crystal design improve quantitative precision and method robustness for routine QA/QC.
• Integrated software workflows and operator mode enable consistent, auditable testing across non-expert users and production environments.
• Robust hardware (LightDrive engine and leakproof cover) minimizes downtime and risk from spills, suitable for industrial laboratories.

Future trends and potential applications

• Greater adoption of multi-reflection ATR accessories in industrial FTIR for on-line and at-line testing as demand grows for faster process analytics.
• Tight integration between spectrometers and cloud-based or laboratory information management systems (LIMS) to streamline data reporting, calibration sharing and regulatory compliance.
• Expanded use of multivariate and machine-learning models for complex matrices (e.g., food blends, contaminated lubricants) to extract actionable metrics from spectral data.
• Development of standardized, validated workflows for regulatory methods to broaden FTIR acceptance in official testing of fuels and food oils.
• Miniaturization and ruggedization to support field-deployable FTIR for remote quality assessment in supply chains and on-site fuel testing.

Conclusion

The Nicolet Summit OA FTIR spectrometer is purpose-built for efficient, reliable analysis of viscous and liquid samples. Its multi-reflection ZnSe trough HATR accessory, reproducible pathlength, robust optics, and workflow-driven software collectively address the practical needs of QA/QC laboratories. The system improves sensitivity and quantitative reliability while reducing sample handling risk and operator training requirements, making it a compelling solution for routine laboratory and process monitoring applications.

References

• Thermo Scientific Nicolet Summit OA FTIR Spectrometer product brief, Thermo Fisher Scientific, 2021.