The stability of Δ9‒tetrahydrocannabinol acetate (Δ9‒THC‒OAc) and Δ8‒tetrahydrocannabinol (Δ8‒THC‒OAc) in e-liquid during storage was investigated. Δ9‒THC‒OAc liquids cartridges were stored at 80℃ or 30℃ for 28 days. relative concentrations cannabinoids the measured by gas chromatography with flame ionization detection. decreased either temperature. Δ9‒THC, a minor impurity, also decreased. Δ8‒...

a gas chromatography mass spectrometry with spike calibration curve method was used to quantify three carbamate pesticides residue in cooked white rice and to estimate the reduction percentage of the cooking process duration. the selected pesticides are three carbamate pesticides including carbaryl and pirimicarb that their mrl is issued by “the institute of standards of iran” and propoxur whic...

Introduction There are many analytical challenges encountered with the extraction and quantification of pesticide residues in difficult sample matrices such as tuber crops, like yam (Dioscorea spp.), taro (Colocasia esculenta) and sweet potato (Ipomoea batatas L.). In our experience, a workflow solution based on extraction using the accelerated solvent extraction technique, followed by determin...

In this review, a full discussion and update of the state-of-the-art of gas chromatography (GC) coupled to all known plasma spectrometers is presented. A brief introductive discussion of the advantages and disadvantages of GC–plasma interfaces, as well as types of plasmas and mass spectrometers, is given. The plasma-based techniques covered include inductively coupled plasma mass spectrometry (...

Physical and chemical properties that may be used to determine the purity of several Fusarium mycotoxins have been investigated. A combination of analytical procedures, which include high performance thin-layer chromatography (HPTLC), liquid chromatography (LC), gas chromatography (GC), gas chromatography/mass spectrometry (GC/MS), ultraviolet spectrometry (UV), and nuclear magnetic resonance (...

Comprehensive 2-dimensional gas chromatography (GC × GC), coupled to either a time of flight mass spectrometry (TOF-MS) or a fast scanning quadrupole MS (qMS) has greatly increased the peak capacity and separation space compared to conventional GC-MS. However, commercial GC × GC-TOFMS systems are not equipped with chemical ionization (CI) and do not provide dominant molecular ions or enable sin...

The ethyl acetate-based multi-residue method for determination of pesticide residues in produce has been modified for gas chromatographic (GC) analysis by implementation of dispersive solid-phase extraction (using primary-secondary amine and graphitized carbon black) and large-volume (20 muL) injection. The same extract, before clean-up and after a change of solvent, was also analyzed by liquid...

Recent developments in trapping efficiency inside ion trap mass spectrometer permitted to lower instrument detection limit (IDL). An IDL of 200fgmul(-1) injected with a signal-to-noise ratio of 5:1 for tetrachlorodibenzo-p-dioxin (TCDD) was obtained by gas chromatography coupled to a quadrupole ion storage mass spectrometer in tandem mode (GC/MS/MS). Coupling large volume programmable temperatu...

Optimization of the Varian Saturn 2200 ion-trap tandem mass spectrometry (IT-MS/MS) system and comparison of its data quality with two other detection methods [electron-capture detection (ECD) and high-resolution mass spectrometry (HRMS)] was pursued by measuring polychlorinated biphenyls (PCBs) levels in fish and shellfish samples. IT-MS/MS methodology provided limits of detection (LOD) compar...

BACKGROUND Methylmalonic acid (MMA), a sensitive biomarker of functional vitamin B12 deficiency, is commonly determined by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods using manual extraction and derivatization of MMA to reduce polarity prior to separation. METHODS In the present study we introduce a semi-automated extractio...