The acetylation of DHLc was followed by UPLC-QTOF using a Phenomenex Luna Omega Polar C18 column (50 x 2.1 mm x 1.6 µm) using water and CH3CN containing 0.1 % of trifluoroacetic acid and an injection volume of 0.5 µL via the following gradient: starting at 40 % CH3CN during 2 min, gradually increasing to 100 % CH3CN from 2 to 5 min, 100 % CH3CN was maintained for 3 more minutes. The percentage of CH3CN was then decreased back to 40 % over 2 more minutes, for a total run time of 10 min.