Document Type
Oral Presentation
Location
Oxford Convention Center, 102 Ed Perry Boulevard Oxford, MS 38655
Event Website
https://www.oxfordicsb.org/
Start Date
25-4-2023 1:00 PM
Description
Natural products from plants, either as pure compounds or as prepared extracts, are widely recognized for their near unlimited potential due to their unmatched and rich chemical diversity. Challenging aspects in the use of natural products include the recognition that unknown compounds are not included in spectral databases, have no chemical standards, and discrimination of structurally similar isomers requires knowledge of isomer presence and potentially difficult and time-consuming chromatographic separations.[FS1] Ion mobility (IM) is a gas phase analytical technique that separates ions based on differences in their size, shape, and charge in the gas phase. Increasingly, IM is being utilized in combination with mass spectrometry (MS) and liquid chromatography-mass spectrometry (LC-MS) for various purposes such as reducing interferences and decreasing LC runtimes for improved throughput, separating challenging isomeric compounds unresolvable via LC, and increasing identification confidence using collision cross section, a unique molecular identifier that can be derived from IM arrival time measurements. A unique feature of combined IM-MS analyses is that different classes of analyte molecules partition into different regions of what can be termed “conformational space” due to class-specific structural folding in the gas phase. Mapping out these CCS vs. m/z trendlines can be a powerful tool that can be applied to extracts to rapidly classify potential unknowns. Herein we report our use of the MOBIE® high-resolution ion mobility system (HRIM) from MOBILion with an Agilent QTOF to determine the CCS values for a series of cannabinoid standards, including isomeric cannabinoids such as delta-8 and delta-9 THC, to map out the conformational space for this class of analytes. The ~250 resolving power of the HRIM MOBILion system allows for the separation of very structurally similar species with CCS differences of ≥ 0.5% in the absence of any chromatographic separation, which enables the construction of a more finely detailed and analytically useful conformational space plot. The application of the developed HRIM-MS methodology and conformational space mapping to various extracts, including hemp, is ongoing.
Recommended Citation
Harris, Rachel A., "More than just a number: utilizing CCS and conformational space analysis to characterize unknowns in complex extracts" (2023). Oxford ICSB. 6.
https://egrove.olemiss.edu/icsb/2023_ICSB/schedule/6
Publication Date
April 2023
Accessibility Status
Searchable text
Included in
More than just a number: utilizing CCS and conformational space analysis to characterize unknowns in complex extracts
Oxford Convention Center, 102 Ed Perry Boulevard Oxford, MS 38655
Natural products from plants, either as pure compounds or as prepared extracts, are widely recognized for their near unlimited potential due to their unmatched and rich chemical diversity. Challenging aspects in the use of natural products include the recognition that unknown compounds are not included in spectral databases, have no chemical standards, and discrimination of structurally similar isomers requires knowledge of isomer presence and potentially difficult and time-consuming chromatographic separations.[FS1] Ion mobility (IM) is a gas phase analytical technique that separates ions based on differences in their size, shape, and charge in the gas phase. Increasingly, IM is being utilized in combination with mass spectrometry (MS) and liquid chromatography-mass spectrometry (LC-MS) for various purposes such as reducing interferences and decreasing LC runtimes for improved throughput, separating challenging isomeric compounds unresolvable via LC, and increasing identification confidence using collision cross section, a unique molecular identifier that can be derived from IM arrival time measurements. A unique feature of combined IM-MS analyses is that different classes of analyte molecules partition into different regions of what can be termed “conformational space” due to class-specific structural folding in the gas phase. Mapping out these CCS vs. m/z trendlines can be a powerful tool that can be applied to extracts to rapidly classify potential unknowns. Herein we report our use of the MOBIE® high-resolution ion mobility system (HRIM) from MOBILion with an Agilent QTOF to determine the CCS values for a series of cannabinoid standards, including isomeric cannabinoids such as delta-8 and delta-9 THC, to map out the conformational space for this class of analytes. The ~250 resolving power of the HRIM MOBILion system allows for the separation of very structurally similar species with CCS differences of ≥ 0.5% in the absence of any chromatographic separation, which enables the construction of a more finely detailed and analytically useful conformational space plot. The application of the developed HRIM-MS methodology and conformational space mapping to various extracts, including hemp, is ongoing.
https://egrove.olemiss.edu/icsb/2023_ICSB/schedule/6