Hemp Chemotype Definition by Cannabinoids Characterization Using LC-ESI(+)-LTQ-FTICR MS and Infrared Multiphoton Dissociation

The development and application of advanced analytical methods for a comprehensive analysis of Cannabis sativa L. extracts plays a pivotal role in order to have a reliable evaluation of their chemotype definition to guarantee the efficacy and safety in pharmaceutical use. This paper deals with the qualitative and quantitative determination of cannabidiol (CBD), tetrahydrocannabinol (THC), cannabinol (CBN), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), and cannabigerol (CBG) based on a liquid chromategraphy-mass spectrometry (LC-MS) method using electrospray ionization in positive mode (ESI+), coupled with a hybrid quadrupole linear ion trap (LTQ) and Fourier transform ion cyclotron resonance mass spectrometer (FTICR-MS). For the first time, structural information of phytocannabinoids is available upon precursor ions’ isolation within the FTICR trapping cell and subsequent fragmentation induced by infrared multiphoton dissociation (IRMPD). Such fragmentation and accurate mass measurement of product ions, alongside collision-induced dissociation (CID) within LTQ, was advantageous to propose a reliable fragmentation pattern for each compound. Then, the proposed LC-ESI(+)-LTQ-FTICR MS method was successfully applied to the hemp chemotype definition of three registered Italian accessions of hemp C. sativa plants (Carmagnola C.S., Carmagnola, and Eletta Campana), thus resulting in the Eletta Campana accession being the best one for cannabis product manufacturing.

Photodissociation Dynamics of Ortho and Meta Fluorophenols: The Origin of Fast Protons

A recent experimental study with time-resolved velocity map imaging demonstrated that the total kinetic energy release spectra obtained from photodissociation of <i>ortho</i> and <i>meta</i> fluorophenols have distinct features after excitation into the origin of the S₁ state. A peak at 6000 cm^-1 was observed for both molecules, while another at 13000 cm^-1dominates the spectrum of <i>ortho</i>-fluorophenol. The peak at 6000 cm^‑1 was assigned to H tunneling. Nevertheless, the 13000 cm^-1 feature remains unassigned. In this work, we performed a theoretical analysis, investigating two hypotheses for explaining the 13000 cm^‑1 signal. The first hypothesis is that it is due to one-photon absorption followed by ionization through resonant multiphoton dissociation. The second hypothesis is that the signal is due to two-photon absorption into a superexcited state, which dissociates yielding an H atom. We discuss the pros and cons of each hypothesis, laying the groundwork for future experiments.

Photodissociation Dynamics of Ortho and Meta Fluorophenols: The Origin of Fast Protons

A recent experimental study with time-resolved velocity map imaging demonstrated that the total kinetic energy release spectra obtained from photodissociation of <i>ortho</i> and <i>meta</i> fluorophenols have distinct features after excitation into the origin of the S₁ state. A peak at 6000 cm^-1 was observed for both molecules, while another at 13000 cm^-1dominates the spectrum of <i>ortho</i>-fluorophenol. The peak at 6000 cm^‑1 was assigned to H tunneling. Nevertheless, the 13000 cm^-1 feature remains unassigned. In this work, we performed a theoretical analysis, investigating two hypotheses for explaining the 13000 cm^‑1 signal. The first hypothesis is that it is due to one-photon absorption followed by ionization through resonant multiphoton dissociation. The second hypothesis is that the signal is due to two-photon absorption into a superexcited state, which dissociates yielding an H atom. We discuss the pros and cons of each hypothesis, laying the groundwork for future experiments.

Photodissociation Dynamics of Ortho and Meta Fluorophenols: The Origin of the Fast Protons

A recent experimental study with time-resolved velocity map imaging demonstrated that the total kinetic energy release spectra obtained from photodissociation of <i>ortho</i> and <i>meta</i> fluorophenols have distinct features after excitation into the origin of the S₁ state. A peak at 6000 cm^-1 was observed for both molecules, while another at 13000 cm^-1dominates the spectrum of <i>ortho</i>-fluorophenol. The peak at 6000 cm^‑1 was assigned to H tunneling. Nevertheless, the 13000 cm^-1 feature remains unassigned. In this work, we performed a theoretical analysis, investigating two hypotheses for explaining the 13000 cm^‑1 signal. The first hypothesis is that it is due to one-photon absorption followed by ionization through resonant multiphoton dissociation. The second hypothesis is that the signal is due to two-photon absorption into a superexcited state, which dissociates yielding an H atom. We discuss the pros and cons of each hypothesis, laying the groundwork for future experiments.