Packed column chromatography, high-resolution gas-chromatography and high pressure liquid chromatography in comparison for the analysis of cannabis constituents.

The identification and the quantitative estimation of cannabis constituents is important for forensic purposes. High resolution gas-chromatography gives better results than gas-liquid chromatography with packed columns, as it shows a better resolution and higher number of constituents. Different quantitative values were found with the two chromatographic procedures. High-pressure liquid chromatography revealed the presence of cannabinoid acids in fresh cut influorescences of cannabis plants. The ratio acid/neutral cannabinoid may be useful in supplying information about the age of the cannabis preparations.