Understanding the effect of spatial positioning of coated blade spray devices relative to the mass spectrometry inlet on different instrument platforms and its application to quantitative analysis of fentanyl and related analogs

Rationale We evaluated the effect that the spatial positioning of coated-blade spray (CBS) devices with respect to the mass spectrometry (MS) inlet has when coupling to diverse MS platforms (i.e., triple quadrupole, linear ion trap and time of flight). Furthermore, as a proof of concept, we evaluated CBS-MS as a tool for quantitation of fentanyl and four analogues on said instruments. Methods Custom-made MS interfaces were made to accurately position the blade in front of the MS inlet. CBS devices, coated with hydrophilic-lipophilic balanced particles, were used for both the optimization of the CBS position and the quantitation of fentanyl and analogues in urine and plasma samples on all instruments. Results The SCIEX triple quadrupole instrument was the most sensitive to the position of the blade due to the presence of a curtain gas flowing laminarly out of the MS inlet. After optimization, the analytical capabilities of CBS on each instrument were assessed and the results obtained on both SCIEX and Waters platforms matched the performance obtained using a more advanced instrument by ThermoFisher Scientific. Furthermore, excellent figures of merit were attained for the quantitation of fentanyl and analogues on both triple quadrupole and linear ion trap platforms. Conclusions We demonstrated that optimization of MS parameters on different instrument vendors and front ends, such as the position of the CBS tip regarding the MS inlet, is vital to exploit the full quantitative potential of this technology. Application of the technology to screen and quantify fentanyl and analogues showed great potential when considering its coupling with portable mass spectrometers for therapeutic drug monitoring and point-of-care applications.