A Second-generation opioid LC-MS/MS assay improves laboratory workflow and capacity.

Area of Science:

• Clinical Chemistry
• Analytical Chemistry
• Forensic Toxicology

Background:

• Opioid drug misuse is a significant public health crisis, driving the need for accurate and efficient diagnostic tools.
• Urine drug screening is crucial for managing patients with chronic pain or opioid use disorder.
• Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the gold standard for confirmatory drug testing due to its high sensitivity and specificity, but its complexity poses challenges.

Purpose of the Study:

• To develop and validate a simplified "dilute-and-shoot" LC-MS/MS assay for opioid testing.
• To leverage upgraded instrumentation to overcome operational complexities of LC-MS/MS.
• To improve assay performance metrics including sensitivity, dynamic range, and turnaround time.

Main Methods:

• Development of a simplified "dilute-and-shoot" LC-MS/MS method for opioid analysis.
• Optimization of chromatographic gradients to resolve isobaric interferences.
• Expansion of analytical ranges using alternative mass transitions and updated quality assurance parameters.
• Validation using 204 clinical samples, comparing results with a previous assay version.

Main Results:

• The new LC-MS/MS method demonstrated good correlation with the previous assay.
• Upgraded instrumentation resulted in enhanced sensitivity and expanded dynamic ranges.
• The simplified assay reduced carryover, eliminating the need for extra injections and chromatogram reviews.
• Turnaround time was reduced, and testing capacity was effectively doubled.

Conclusions:

• The developed "dilute-and-shoot" LC-MS/MS assay offers a streamlined and efficient approach to opioid drug testing.
• This method enhances laboratory efficiency by improving sensitivity, reducing manual review, and increasing throughput.
• The improvements serve as a valuable model for clinical laboratories transitioning to new mass spectrometry instrumentation.