Determination of the new psychoactive substance dichloropane in saliva by microextraction by packed sorbent – Ion mobility spectrometry

Abstract

A simple procedure based on microextraction by packed sorbent (MEPS) has been proposed for the extraction of dichloropane in oral fluids and its determination by ion mobility spectrometry (IMS). Extraction conditions such as type of sorbent (octyl and octadecyl silica), sample pH, number of sample loadings, and elution volume were evaluated to obtain the most appropriate values. Dichloropane was extracted from saliva samples using C8 MEPS, loading with 100 μL sample (adjusted to pH 7) in 4 cycles, washing with 100 μL deionized water, and eluting with 50 μL 2-propanol in 10 cycles. The proposed MEPS procedure has been validated in terms of linearity, accuracy, and precision. A limit of detection of 30 μg L−1 was obtained for dichloropane determination in saliva. The analysis of field and synthetic saliva samples spiked with dichloropane at concentration levels from 250 to 750 μg L−1 provided relative recoveries between 85 and 110%, using the proposed MEPS-IMS procedure. Field oral fluid samples were collected from healthy individuals, blind-spiked from 92 to 278 μg L−1, and analysed by IMS and gas chromatography-mass spectrometry, being the results obtained from both methods statistically comparable. Thus, the proposed MEPS-IMS procedure involves a simple, sensitive, and accurate analysis of dichloropane in saliva.