Intelligent Reflex Fast Screening for Drugs in Urine: data-dependent reinjection logic for screening and confirmation of presumptive positives

Importance of the Topic

Rapid and reliable screening for drugs of abuse in biological matrices is critical in clinical, forensic, and workplace testing. Traditional LC/MS workflows can be time-consuming when analyzing large sample batches, especially when most samples are negative. The intelligent reflex fast-screening approach integrates data-dependent logic to minimize unnecessary confirmatory runs and accelerate throughput.

Objectives and Overview of the Study

This poster describes the implementation and performance evaluation of an intelligent reflex workflow within Agilent MassHunter 12 software coupled to LC/TQ instrumentation. The aim was to demonstrate how a shortened screening method (~3 min runtime) can flag presumptive positives for automated reinjection using a longer confirmatory method (~15 min), thereby reducing total analysis time for a 96-well plate containing 12 positive samples.

Methodology and Instrumentation

The experiment simulated urine drug screening using synthetic urine spiked with a ForTox drug standard. Twelve positive samples were randomly distributed among 96 wells. Key elements of the workflow:

• Screening Method: 3 min fast gradient on a Poroshell 120 EC-C18 2.1×50 mm column, 0.6 mL/min flow, positive ESI, MRM transitions with 10 ms dwell time.
• Confirmatory Method: 15 min conventional gradient on a Poroshell 120 EC-C18 2.1×100 mm column, enhanced separation and selectivity for quantitation.
• Instrumentation: Agilent 6475 triple quadrupole LC/MS, Infinity II 1290 binary pump, multisampler, column compartment, MassHunter 12 Acquisition and Quantitative Analysis software.
• Data-Dependent Logic: Intelligent Reflex feature enabled ’Fast Screening Append’ workflow. Threshold concentrations in the quant method triggered reinjection scheduling.

Key Results and Discussion

Quality-control injections confirmed all target analytes were detectable under both methods, with improved sensitivity and specificity in the confirmatory run. In a full 96-sample batch:

• Traditional approach (15 min per sample) would require 1 440 min (24 h) of runtime.
• Intelligent reflex workflow required 468 min (3 min×96 + 15 min×12), a 67 % reduction in total analysis time.
• Negative samples progressed directly through the 3 min screening, while presumptive positives were automatically queued for confirmatory analysis.

Benefits and Practical Applications

The intelligent reflex fast-screening workflow delivers:

• Substantial time savings for high-throughput urine drug testing.
• Automated worklist management and decision logic, reducing manual oversight.
• Maintenance of confirmatory quality for positive samples without compromising screening speed.

Future Trends and Possibilities

Integration of intelligent reflex logic in LC/Q-TOF and other tandem MS platforms can expand fast-screening applications to wider panels of compounds. Further refinements may include adaptive thresholding, real-time data analytics, and integration with laboratory information management systems (LIMS) for fully automated, high-throughput workflows.

Conclusions

The intelligent reflex fast-screening protocol in MassHunter 12 demonstrates significant productivity gains for urine drug analysis by combining a rapid screening run with automated, data-driven reinjection for confirmatory quantitation. This approach reduces instrument runtime by over 60 % for batches with low positivity rates, while preserving analytical rigor for positive detections.

Reference

Lee Bertram, Patrick Batoon. Intelligent Reflex Fast Screening for Drugs in Urine: Data-Dependent Reinjection Logic for Screening and Confirmation of Presumptive Positives. ASMS 2023, Poster TP 458. Agilent Technologies Inc., Santa Clara, CA.