Improving Data Analysis using Vacuum Ultraviolet Automated Library Integrated Deconvolution on Gas Chromatography Vacuum Ultraviolet Spectroscopy Data
Access changed 9/21/23.
Gas chromatography (GC) coupled to vacuum ultraviolet (VUV) spectroscopy and mass spectrometry (MS) can provide confident chemical identities. Vacuum Ultraviolet Automated Library-Integrated Deconvolution (VALID), a custom-built software, is used to deconvolute congested GC-VUV data. This project assesses the performance of VALID and discusses methods to improve GC-VUV data analysis. Perfume and frankincense-based essential oil samples were injected into a home-built tandem GC/VUV-MS instrument and analyzed both manually and via VALID. VALID allowed for successful identification of GC-VUV retention-time convoluted analytes that could not be detected by manual analysis; analyte identifications were confirmed by GC retention index (RI) values. To address the limited dynamic range of the VUV spectrometer, GC-VUV data from samples at varying concentrations were obtained to acquire suitable VUV spectra that exhibited sufficient signal-to-noise levels with no signal saturation. More analytes were identified via the combination of manual VUV analysis, VALID, and GC RI analysis than using each of the three data analysis approaches alone. To address the limited size of the existing commercial VUV library, GC-MS library-searching was used to identify GC-VUV-convoluted compounds that were deconvoluted by VALID; these GC-MS identifications were used to label VALID-extracted VUV spectra for cost-effective and rapid expansion of the VUV libraries.