Tandem Mass Spectrometry (MS/MS) Utilizing Electron Impact Ionization and Multiple Reaction Monitoring for the Rapid, Sensitive, and Specific Identification and Quantitation of Morphine in Whole Blood*

Publisher Website
Google Scholar
Abstract
A single step liquid-liquid extraction procedure followed by pentafluoropropionic anhydride derivatization was developed for the analysis of free morphine in blood. The specificity of the method was enhanced with the use of tandem mass spectrometry (MS/MS) using multiple reaction monitoring. Two molecular transitions were monitored. The first transition was where the first quadrupole (Q1) transmits the molecular ion of morphine-3,6-dipentafluoropropionate, 577. The 577 ion undergoes subsequent collision induced dissociation with argon and the last quadrupole (Q3) then transmits the 414 daughter ion. The second transition monitored was where Q1 transmits the 414 base peak and Q3 transmits the resultant 266 daughter ion. Deuterated morphine was included as an internal standard and analyzed similarly. Morphine was confirmed only in instances where both the m/z 577 to 414 and 414 to 266 transitions occurred simultaneously. Linear and reproducible calibration curves have been obtained for morphine at concentrations from 1.0 to 500 ng/mL achieving correlation coefficients of greater than 0.994. A signal-to-noise ratio of approximately 5:1 was observed for the 1.0-ng/mL samples.