Simultaneous Quantification of 25 Fentanyl Derivatives and Metabolites in Oral Fluid by Means of Microextraction on Packed Sorbent and LC-HRMS/MS Analysis.

Flaminia Vincenti,Adolfo Gregori,Roberta Curini,Svetlana Pirau,Manuel Sergi,Camilla Montesano,Fabiana Di Rosa

doi:10.3390/molecules26195870

Abstract

Fentanyl and fentalogs’ intake as drugs of abuse is experiencing a great increase in recent years. For this reason, there are more and more cases in which it is important to recognize and quantify these molecules and related metabolites in biological matrices. Oral fluid (OF) is often used to find out if a subject has recently used a psychoactive substance and if, therefore, the person is still under the effect of psychotropics. Given its difficulty in handling, good sample preparation and the development of instrumental methods for analysis are essential. In this work, an analytical method is proposed for the simultaneous determination of 25 analytes, including fentanyl, several derivatives and metabolites. OF was collected by means of passive drool; sample pretreatment was developed in order to be fast, simple and possibly semi-automated by exploiting microextraction on packed sorbent (MEPS). The analysis was performed by means of LC–HRMS/MS obtaining good identification and quantification of all the analytes in less than 10 min. The proposed method was fully validated according to the Scientific Working Group for Forensic Toxicology (SWGTOX) international guidelines. Good results were obtained in terms of recoveries, matrix effect and sensitivity, showing that this method could represent a useful tool in forensic toxicology. The presented method was successfully applied to the analysis of proficiency test samples.

Highlights

Fentanyl and its analogues are increasingly being used as drugs of abuse worldwide
To obtain a complete fragmentation pattern of the analytes, different runs were performed in full-scan data-dependent acquisition mode, each one with three different collision energies (CE) as described in a previously published method [19]
The mobile phases were selected thanks to the expertise gained in the field of new psychoactive substances (NPS) analysis and opioids; in particular, phases were water mM ammonium formate (phase A), constituted by 10 mM ammonium formate acidified with 0.1% of HCOOH, was evaluated to perform a better ionization of all target analytes in the heated electrospray ionization source (H-ESI) source, as previously described by Montesano et al [20], while phase B was chosen since in the literature it is widely demonstrated that mixing different percentages of MeOH and MeCN can improve the chromatographic separation of several types of analytes if compared with the separation provided by the use of single solvents [21]

Summary

Introduction

Fentanyl and its analogues are increasingly being used as drugs of abuse worldwide. In the US, an impressive wave of opioid overdose cases is currently being driven by these molecules [1], which may be classified as synthetic opioids. For what concerns the determination of fentanyl and/or its analogues in this matrix, a few methods have already been published These include two recent publications from Palmquist et al [3,9] and a number of papers comprising fentanyls in combination with other opioids [10] and new psychoactive substances (NPS) [11,12,13]. In all of these published methods, traditional sample preparation techniques such as dilution, SPE or LLE were used

Methods

Results

Conclusion