Acquity ultra high performance liquid chromatography uplc

Five amino acids, including two acidic amino acids, Asp and Glu, and three basic amino acids, Arg, His, and Lys were chosen. The reaction conditions were a concentration of 5% amino acids, reaction time of 1 h, liquid-solid ratio of 20 mL/g, and a temperature of 120 °C. The extract was collected and filtered through a 0.22-μm filter. The analysis was performed using an Acquity Ultra High-Performance Liquid Chromatography (UPLC) (Waters, Manchester, UK). The process was repeated three times for all samples.

Waters Acquity Ultra High-Performance Liquid Chromatography (UPLC) with a tunable ultraviolet (TUV) detector (Waters™, Mississauga, ON, Canada) was used for cannabinoid analyses. Each extract was further diluted 50× (for analysis of major cannabinoids) and 4× (for analysis of minor cannabinoids and terpenes) using HPLC-grade methanol (Thermo Fisher Scientific, Waltham, MA, USA). One-milliliter samples of each extract were pipetted into HPLC vials for cannabinoid analysis. The Waters cortex column was used to separate cannabinoids with a sample injection volume of 2 μL and a column temperature of 30 °C, equipped with an isocratic gradient pump. Mobile phase A consisted of 22% reverse osmosis water and 0.1% formic acid (Sigma-Aldrich, Saint Louis, MI, USA). HPLC-grade acetonitrile (78%) (Thermo Fisher Scientific, Waltham, MA, USA) was used for mobile phase B. Quantification of the cannabinoids was performed using an external calibration curve developed using 7 standard cannabinoids (LGC standards, Manchester, NH, USA and Sigma Aldrich, Saint Louis, MI, USA).