Analysis of LSD
The only analogue of LSD to receive widespread interest is lysergic acid N-(methylpropyl)amide (LAMPA), and any analytical technique should be capable of separating LAMPA from LSD. The presence of LSD may be signalled early by placing the suspect paper under long-wave length ultraviolet (UV) light. The presence of LSD is indicated by a blue fluorescence.
Colour test Van Urk’s reagent gives a purple colour. Some difficulty may be encountered in obtaining an unequivocal identification of LSD because of its low dosage (50 lg or less). However, if the sample is concentrated, a satisfactory analysis can be achieved. Place a suspect LSD square in a glass vial and cover with methanol. After soaking (or sonicating) for 10–20 min, the methanol can be trans ferred to a vial for analysis. Another method is to add concentrated ammonia (about two drops) to the methanol.
Quantitative analysis and comparison of LSD HPLC is the method of choice for quantitative analysis of LSD using a solvent mixture of methanol and water (1:1) (McDonald et al. 1984). In some instances, a comparison is requested between one square of LSD and a large sheet of perforated squares. This can be an easy matter if the design on the large sheet spreads over the whole sheet and the ‘missing’ square fits neatly into the pattern . In other instances the design may be on every individual square (or there may be no design). In such cases, it is necessary to examine the colour, design and/or dimensions of the squares and the perforation pattern. Chemical comparisons can also be under taken, but squares from the same large sheet can vary in the amount of LSD on each.
In addition to chromatographic separation, LSD can be discriminated from other ergot alkaloids by the MS fragmentation pattern. For example, the presence in the LSD spectrum of a m/z 100 fragment nearly as intense as the m/z 111 fragment serves to differentiate LSD from other disubstituted amides.
