Meet the Thermo Scientific™ Vanquish™ Charged Aerosol Detector P Series

Importance of the Topic

Charged aerosol detection (CAD) brings near-universal sensitivity to liquid chromatography by responding to all non-volatile and many semi-volatile compounds with a consistent signal. This capability addresses the limitations of traditional detectors like UV (which requires chromophores) and MS (which requires ionization), enabling accurate quantitation across a broad range of analytes in pharmaceuticals, biomolecules, foods, specialty chemicals, and polymers.

Objectives and Study Overview

This whitepaper introduces the Thermo Scientific Vanquish Charged Aerosol Detector P Series and examines its performance characteristics. Key aims include:

• Demonstrating uniform response across diverse analytes via flow injection and chromatographic separations.
• Evaluating sensitivity, dynamic range, and compatibility with gradient elution.
• Highlighting seamless integration with Vanquish HPLC/UHPLC systems and Chromeleon CDS for compliant workflows.

Methodology and Instrumentation Used

The CAD operates in three stages:

• Nebulization: Mobile phase is converted into droplets and dried into analyte particles using the FocusJet concentric nebulizer.
• Charging: A stream of charged nitrogen collides with particles, imparting a charge proportional to analyte mass.
• Detection: An electrometer measures particle charge, producing a signal directly related to analyte quantity.

Instrumentation highlights include the Vanquish CAD P Series detector, integrated diverter valve for matrix diversion, temperature‐controlled evaporation and charging zones, and compatibility with Vanquish Core, Flex, and Horizon systems.

Main Results and Discussion

Flow injection analysis of 22 non-volatile compounds yielded a relative response deviation of only 7.2%, confirming exceptional uniformity. Key performance metrics:

• Sensitivity up to 10× higher than refractive index and evaporative light scattering detectors.
• Linear dynamic range spanning up to four orders of magnitude.
• Compatibility with gradient elution, enabling superior resolution without baseline shifts.

Advanced features such as inverse gradient compensation using dual pumps and automated calculation wizards ensure uniform response throughout gradient runs. Method translation tools in Chromeleon CDS facilitate seamless migration from earlier CAD models while maintaining 21 CFR Part 11 compliance.

Benefits and Practical Applications of the Method

Uniform quantitation with a single calibrant simplifies impurity and excipient analysis when standards are scarce or costly. Applications include:

• Compendial assays in pharmaceuticals (ASTM, EP, USP compliance).
• Quantitation of polysorbates and lipids in biopharma formulations.
• Analysis of carbohydrates, polymers, and specialty chemicals.
• Coupled detection workflows with UV or MS for comprehensive profiling of complex samples.

Future Trends and Potential Applications

Emerging uses for CAD include advanced characterization of lipid nanoparticles in mRNA therapeutics, high-throughput screening in QA/QC labs, and integration with multimodal detection platforms. Anticipated developments:

• Enhanced software-driven method optimization and automation.
• Expanded compliance features for regulated environments.
• Broader adoption in environmental and food safety testing.

Conclusion

The Vanquish Charged Aerosol Detector P Series delivers robust, near-universal detection with high sensitivity and reproducibility. Its compatibility with gradient elution, seamless integration into established LC systems, and regulatory compliance capabilities make it a versatile tool for research, development, and routine quality control across diverse industries.

Reference

Application note AB003866
Application note AN003506