Foods and Contaminants Analysis Using Multidimensional Gas Chromatography: An Update of Recent Studies, Technology, and Applications

Detection of the Synthetic Coolant Menthone 1,2-Glycerol Ketal in an e-Liquid and in Electronic Waterpipe Aerosols Therefrom

“…The results showed no evidence supporting the possibility of MGK being detected as an analytical artifact because the semiquantitative estimate from the GC × GC-TOFMS data for the amount of MGK present in the Menthol e-liquid (∼60 μg/mL) does not exceed the LC–MS/MS-measured concentration of MGK (mean = 170 μg/mL, standard deviation = 26 μg/mL). Even so, the semiquantitative approach used to estimate MGK concentrations is based on an untested assumption that the sensitivity for a given chemical is identical to the sensitivity for the IS, and the accuracy of the semiquantitative estimate may be affected by the modulation that is used between columns in a GC × GC-TOFMS instrument . In light of these limitations, another investigation to develop a quantitative GC method for MGK could be useful to rigorously investigate the hypothesis about artifact detections of MGK.…”

“…Even so, the semiquantitative approach used to estimate MGK concentrations is based on an untested assumption that the sensitivity for a given chemical is identical to the sensitivity for the IS, and the accuracy of the semiquantitative estimate may be affected by the modulation that is used between columns in a GC × GC-TOFMS instrument. 17 In light of these limitations, another investigation to develop a quantitative GC method for MGK could be useful to rigorously investigate the hypothesis about artifact detections of MGK. More generally, we suggest that LC− MS/MS methods may be valuable as a complement to GC methods in future research to study the occurrence of ketals� and possibly of acetals�in e-liquids.…”

“…The flavor profiles of the four e-liquids were characterized using nontargeted chemical analysis by two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC-TOFMS), which can be applied in nontargeted analyses to identify a wide variety of compounds of interest. − For each e-liquid, triplicate dilutions were prepared by first adding to a glass vial (for each dilution) 10 μL of the e-liquid and determining the precise mass (±0.0001 g) of the e-liquid. The next step was to dilute the e-liquid into 2 mL of isopropyl alcohol that contained 200 ng/mL of the internal standard (IS) acenaphthene- d 10 (and the other five isotopically labeled internal standards in the same mixture, as listed above).…”

Analysis of GC × GC fingerprints from medicinal materials using a novel contour detection algorithm: A case of Curcuma wenyujin

“…Data mining from two-dimensional (2D) fingerprints is a key area of study for chemometric scholars [ [25] , [26] , [27] , [28] ]. The core challenge lies in quickly and accurately detecting 2D peaks and extracting relevant information.…”