samples of drug-type cannabis, one non-psychotropic cannabis sample and two
fibre-type cannabis samples. C18 (4.6 mm150 mm3.5μ particle size)
HPLC column, and a gradient mobile phase composed of 50 mM ammonium
formate (pH 3.75) and acetonitrile were used. Neutral cannabinoids were detected at
228 nm while, acidic cannabinoids at 270 nm. Diazepam was the internal standard.
It is an accurate method for the quantification of major cannabinoids in cannabis
plant and can be used for plant phenotype determination but the run is relatively
long (36 min) (De Backer et al. 2009 ).
7.5.3 Ultra-Performance Liquid Chromatography (UPLC)
Ultra-Performance Liquid Chromatography (UPLC) offered the advantages of
increased sensitivity and resolution together with reduced analysis time by using
columns with particle size of 2μm and smaller. Thus, a greater resolution is
achieved between peaks, or the same resolution can be achieved in less time. Due to
the better sensitivity a rapid resolution, UPLC was widely used in forensic chem-
istry to quantitate cannabinoids and their metabolites in biologicalfluids (urine,
blood, and saliva). Few publications on the application of UPLC for cannabis
products analysis were found in literature.
UPLC/UV and UPLC-MS-MS were described and validated by Seok et al. for the
analysis of cannabinoids in different types of food products as well as in herbal and
dietary supplement samples (tablets, capsules, powders, liquids, cookies and candies).
UPLC/UV validation was performed on an Acquity UPLC™system (Waters, Milford,
CT, USA) equipped with a photodiode array detector. The column was a Waters
Acquity UPLC HSS C18 (2.1 mm150 mm, 1.8μm particle size), with aflow rate
of 0.18 mL/min, the UV detection was set at 210 nm. The mobile phase was gradient
and consisted of 25 mM sodium phosphate and 0.01% sodium hexane sulfonate in
deionized water adjusted to pH 3 with phosphoric acid (solventA) and acetonitrile
(solvent B). For the LC–MS-MS analysis, a Waters Acquity UPLC BEH C18 column
(2.0 mm100 mm, 1.7μm) was utilized, and theflow rate was 0.25 mL/min. The
mobile phase was composed of solvent A (0.1% formic acid in distilled water; D.W)
and solvent B (0.1% formic acid in acetonitrile). MS was conducted in electrospray
ionization (ESI) mode. The total run time is 15 minuites. Both methods were validated
for linearity, precision, accuracy. The authors claimed that the method is sensitive and
reproducible and can be used for rapid and accurate screening of cannabinoids present
in food (Heo et al. 2016 ).
A simple, fast and efficient method was developed for the analysis of 30 can-
nabis plant samples (Flowering buds, hashish and leaves) at the University of
Mississippi using Ultra High Performance Supercritical Fluid Chromatography
(UHPSFC) coupled with photodiode array (PDA) and electrospray ionization/mass
spectrometry (ESI-MS) detection. Nine cannabinoids including CBD,Δ^8 -THC,
THCV,Δ^9 -THC, CBN, CBG, THCA-A, CBDA and CBGA were quantitatively
determined. The chromatographic separation was achieved using a
178 M.M. Radwan et al.