HRMS Detector for the New HILIC CBD Method Development in Hemp Seed Oil

The cannabis analysis has gained new importance worldwide due to the rapid expansion of the hemp global market. Many reverse phase high performance liquid chromatography (HPLC) methods have been developed to analyze cannabidiol (CBD) and its analogues due to the nice fit with their log P values at around 6. However, when CBD was blended with hemp seed oil in consumer, cosmetic, and food industries, the high content of triacylglycerides (TAGs) from hemp seed oil were retained and accumulated inside C₁₈ columns with the common mobile phases and caused a column pressure increase and ghost peaks after continuous sample injections. Coupled with the chemical profile from high resolution mass spectrometry (HRMS) detection, a novel hydrophilic interaction liquid chromatography (HILIC) CBD quantitation method was developed, specifically for CBD blended hemp seed oil materials, which can overcome the matrix buildup in reverse phase columns. The zwitterionic (ZIC)-cHILIC column containing a dense water layer on the stationary phase surface provided a stable partitioning separation mechanism to separate the CBD from TAGs in hemp seed oil. This water layer favors the sustaining NH₄F buffer ions, which can maximize the salting-out action and help reduce the adsorptive interaction between TAGs and stationary phase sulfobetaine materials. The high percentage of acetonitrile (99%) contributed to method sensitivity and reduced instrument maintenance time. The method was developed and validated for the first time. It has been successfully applied to quantify CBD content in hemp seed oil samples, thus demonstrating it to be a useful tool for both quality control and safety assurance in CBD hemp seed oil raw materials and related products.