A Rapid Assay for the Simultaneous Determination of Nicotine, Cocaine and Metabolites in Meconium Using Disposable Pipette Extraction and Gas Chromatography–Mass Spectrometry (GC–MS)

Abstract

Drug abuse by pregnant women is considered a serious public health problem worldwide. Meconium is the first excretion in newborns and has been used as an alternative matrix to evaluate in utero drug exposure. Solid phase extraction (SPE) is widely employed to prepare and clean up samples in the field of forensic analysis. Most SPE products require large volumes of solvent, which culminates in longer sample processing times and increased cost per sample. Disposable pipette extraction (DPX) tips have been used as an alternative to traditional SPE cartridges. They combine efficient and rapid extraction with reduced solvent consumption. The purpose of this study was to develop and validate a method to determine nicotine, cotinine, cocaine, benzoylecgonine, cocaethylene and methyl ester anhydroecgonine in meconium using DPX and gas chromatography-mass spectrometry (GC-MS). Validation results indicated that extraction efficiency ranged 50-98%, accuracy 92-106%, intra-assay precision 4-12% and inter-assay precision 6-12%. Linear calibration curves resulted in R(2) values >0.99, limits of detection ranged from 2.5 to 15 ng/g and the limit of quantitation from 10 to 20 ng/g. The DPX-GC-MS method was shown to selectively analyze trace concentrations of drugs in meconium samples. Finally, the developed and validated method was applied to 50 meconium samples.

Miniaturized Salting-Out Assisted Liquid-Liquid Extraction Combined with Disposable Pipette Extraction for Fast Sample Preparation of Neonicotinoid Pesticides in Bee Pollen

“…In addition, it allows for automated and high-throughput preparation when combined with the liquid handling system [18,19]. This sample preparation method has been widely used in the analysis of drugs [14,[18][19][20][21][22][23][24], pesticide residues [16,17,[25][26][27][28][29][30], heavy metal ions [31], and environmental contaminants [32][33][34][35]. In the present work, the parameters of DPX were systematically investigated on the clean-up of neonicotinoid pesticides in bee pollen.…”

Voltammetric Determination of Aclonifen at a Silver Amalgam Electrode in Drinking and River Water

“…Due to its high sensitivity and simplicity the new method can be a useful alternative to chromatographic methods for the purpose of screening for AC residues in the environment. The method is sensitive and fast, it is performed on a portable electrochemical instrument (Palmsens), and it would be easy to make the method as a whole suitable for field measurements by employing a pipette tip SPE as in [29]. This is possible due to the increased mechanical stability of m-AgSAE compared to traditional electrodes utilizing liquid mercury.…”

A quantitative LC–MS/MS method for simultaneous determination of cocaine and its metabolites in whole blood

“…However, the UV method cannot be used to determine EME, ECG, NEME, EEE, and NEEE due to the lack of a conjugated system in these compounds. Several GC-MS and LC-MS/MS methods have been reported for simultaneous determination of cocaine and its metabolites including BE, norcocaine, cocaethylene, EME, and ECG [29–34]. These methods provided great separation, sensitivity, and selectivity.…”