Industrial Quality Control and Workflow Integration with the witec360 Platform

Introduction

Pharmaceutical manufacturing requires analytical technologies that provide reliable chemical information while integrating seamlessly into industrial quality control workflows. Beyond research applications, production environments demand robustness, reproducibility, automation capability, and regulatory compliance support.

The chemical identity, spatial distribution, and solid-state form of active pharmaceutical ingredients (APIs) directly influence product performance, stability, and patient safety. Even minor variations in polymorphic form or blend homogeneity can affect therapeutic efficacy.

Confocal Raman microscopy combines molecular specificity with high spatial resolution and non-destructive analysis. The microscopy and software provides features that support institutional and regulatory processes at an operational level. Functions such as multi‑user role management, internal calibration routines, automated reporting, and reproducibility features help maintain consistent procedures and clear data handling. The witec360 platform further extends these capabilities into industrial environments by enabling fast confocal Raman imaging, spectral acquisition and guided evaluation, supporting structured workflows and reliable analytical execution.

Raman setup in a pharmaceutical environment.

Technology Overview

Raman spectroscopy is based on the inelastic scattering of monochromatic laser light. During interaction with molecular vibrations, a small fraction of scattered photons undergoes a characteristic frequency shift. This shift reflects the molecular structure and provides a highly specific chemical fingerprint.

When combined with confocal microscopy, Raman spectroscopy enables spatially resolved chemical imaging in two and three dimensions. This allows both identification and localization of compounds within complex pharmaceutical formulations.

Advantages over other methods

• No sample preparation required.
• Non-destructive and contact-free.
• High chemical specificity and spatial resolution.

Key features of witec360 systems

• True confocal Raman imaging for 3D chemical mapping.
• Rapid data acquisition through highly sensitive detectors.
• Possibility to combine with AFM or further correlative technologies for multimodal analysis.

The witec360 platform is built on a true confocal optical design, ensuring high lateral and axial resolution while minimizing background signals, such as fluorescence. This architecture is particularly advantageous for heterogeneous samples such as coated tablets, granulates, or multilayer systems.

Hexalight is the innovative spectrometer at the heart of the witec360 Raman microscopes. Its pioneering, lens‑based design eliminates mirrors and sets new benchmarks for throughput and spectral versatility, offering exceptional broadband performance. Hexalight’s outstanding sensitivity helps accelerate workflows and significantly reduce integration times, which enables large-area mapping and screening applications suitable for industrial fail analysis and quality control.

TrueSurface technology allows Raman measurements on uneven or curved sample surfaces without refocusing artifacts. Automated z-scanning enables volumetric chemical imaging and depth profiling without destructive cross-sectioning.

The integrated software supports automated spectral clustering, chemical segmentation, and advanced visualization options, while standardized data export ensures fully traceable workflows.

Applications in Industrial Pharmaceutical Workflows

Raman microscopy addresses critical analytical questions in pharmaceutical research as well as in product and process development. Within industrial environments, reproducibility and automation are as important as analytical performance.

Polymorphism analysis enables reliable differentiation of crystalline forms of APIs, supporting solid-state stability studies and batch verification. API distribution mapping provides quantitative insight into blend homogeneity and dose uniformity. Contamination analysis enables rapid identification of foreign particles. In addition, Raman spectroscopy supports Process Analytical Technology (PAT) strategies for atline measurement approaches. Standardized measurement routines reduce operator dependency and increase batch-to-batch reproducibility.

Typical Pharmaceutical Applications and Workflow Integration

Industrial Measurement Examples

API Distribution in a Pharmaceutical Tablet

A tablet containing one API and multiple excipients was analyzed using confocal Raman imaging on the witec360 platform. Surface mapping was performed with a lateral resolution of approximately 300 nm. Subsequent depth profiling achieved an axial resolution of approximately 900 nm.

Automated cluster analysis enabled objective segmentation of chemically distinct regions. The resulting chemical maps visualize the spatial distribution of API and excipients and verify the blend homogeneity. Deviations can be detected at early stages of production, enabling corrective actions.

Chemical Raman map of tablet showing API and excipient distribution.

Polymorphic Distribution of Acetylsalicylic Acid (ASA)

Using high spectral resolution and confocal imaging, different polymorphic forms of ASA were identified and spatially localized within a single tablet. The Hexalight spectrometer design ensures sufficient sensitivity and spectral resolution to resolve subtle spectral differences between crystalline phases.

Automated spectral classification supports rapid polymorph differentiation, strengthening stability assessment and batch validation workflows.

Raman polymorph map of ASA showing spatial phase distribution.

3D Coating Analysis and Depth Profiling

Three-dimensional Raman imaging enables non-destructive analysis of coated tablets. Z-stack acquisition combined with automated focus control (TrueSurface) that allows accurate determination of coating thickness, surface morphology and internal API distribution.

This volumetric approach provides detailed insight into multilayer systems and supports optimization of coating processes without destructive cross-sectioning.

Raman depth profile of coated tablet.

Advantages for Industrial Pharmaceutical Environments

The witec360 systems are to support both, fundamental research tasks and industrial, repetitive operations through robust optical architecture, high-throughput spectroscopy, and automated measurement protocols.

The combination of high chemical specificity, submicron spatial resolution, and a compliance-oriented ecosystem - spanning hardware, software, and application support - makes Raman microscopy suitable not only for research laboratories but also for regulated quality control settings.

Conclusion

The witec360 Raman imaging platform provides a comprehensive analytical solution for industrial pharmaceutical material characterization. From polymorph identification to automated API mapping and three-dimensional coating analysis, the system integrates high-resolution chemical imaging into standardized quality control workflows.

By combining analytical performance with workflow compatibility and automation, Raman microscopy becomes a key enabling technology for modern, data-driven pharmaceutical manufacturing.