An Innovative Approach to Q-TOF High Resolution Accurate Mass Analyte Screening Using an Improved Software Algorithm and Screener Tool

Importance of the Topic

High-resolution, accurate mass screening of complex samples is essential for reliable detection of a large number of targets and suspects in various fields including pharmaceutical QA/QC, forensic toxicology and environmental monitoring. The development of robust data mining algorithms is critical to manage matrix variability, broad concentration ranges and to minimize false positive/negative outcomes in routine analyses.

Study Objectives and Overview

This study aimed to demonstrate a proof of principle for screening a panel of over 200 analytes and suspects in a single eight-minute LC–Q-TOF analysis. The improved software algorithm SureMass and an interactive Screener Tool were evaluated for reproducibility, mass accuracy (<5 ppm) and data processing speed across high and low concentration controls.

Methodology and Instrumentation

• Chromatography: 8 min reverse phase gradient on Poroshell 120 EC C18 column (100 × 2.1 mm). Mobile phases: 0.01% formic acid with 5 mM ammonium formate in water (A) and methanol (B).
• Gradient: 10%→95% methanol over 8 min.
• Mass spectrometry: Agilent 6546 Q-TOF LC/MS in positive mode; scan rates 3 Hz (MS-only) and 9 Hz (All Ions at 0, 20, 30 eV).
• Source settings: AJS-ESI at 0.5 mL/min, nozzle voltage 500 V, sheath gas 360 °C/11 L/min, dry gas 300 °C/10 L/min, nebulizer 55 psi, capillary 3750 V.
• Data processing: SureMass algorithm for profile data, extracting ridges and features by combining monoisotopic mass, isotope spacing, abundance and retention time information.

Main Results and Discussion

• Near 100% identification rate for 200+ targets with mass match scores in the high 90% range for both low and high concentration controls (N=10 replicate injections).
• Mass accuracy below 5 ppm across all targets, even at very low and very high abundances, demonstrating robust performance of the SureMass algorithm in both MS-only and All Ions acquisition modes.
• SureMass effectively handles saturation effects in centroided data, avoiding false negatives due to split peaks or mass shifts.
• The Screener Tool’s color-coded interface (green/amber/red) simplifies batch review, significantly reducing analyst evaluation time.
• Data processing speed is substantially faster with SureMass, supporting large target lists without compromising accuracy.

Benefits and Practical Applications

• Comprehensive screening of hundreds of analytes in a single, short analysis run.
• Consistent high mass accuracy supports confident identification in QA/QC and forensic workflows.
• Reduced false positive/negative rates enhance data reliability in regulatory environments.
• User-friendly Screener Tool streamlines data review and reporting.
• Compatibility with both MS-only and All Ions acquisition offers flexibility for different application needs.

Future Trends and Opportunities for Use

• Expansion of target databases to include emerging contaminants and novel psychoactive substances.
• Integration of machine learning to further refine feature extraction and reduce manual review.
• Application in diverse fields such as environmental screening, food safety and clinical research.
• Development of real-time processing for on-the-fly screening in high-throughput laboratories.

Conclusion

The SureMass data mining algorithm, combined with the Agilent 6546 Q-TOF LC/MS and Screener Tool, offers a rapid, accurate and reproducible platform for high-resolution screening of extensive analyte panels. Its robust performance, user-friendly interface and high mass accuracy make it an effective solution for routine analytical workflows requiring comprehensive screening.

Reference

1. Karen E. Yannell and Manuel Gomez; Agilent Technologies, Inc.; Publication 5994-1744EN.