Forensic detection of marijuana trace

In this study, we compared the use of both chemical and biological tests for precise screening. Marijuana leaves had been treated in simulated conditions according to the way they are consumed; leaves materials were boiled in water for 5 min to 8 h, dried in hot-air oven, air-dried in shade and sunlight, and burned to black and white ashes. The THC band was detected in the TLC fingerprints of all samples, except the white ash extract. In contrast, the 197-bp mitochondrial trnL-F fragment was amplified in two samples, i.e., the DNA extracted from fresh marijuana leaves that were boiled for 5 min and some of the dried marijuana sample. The results suggested that TLC was a robust method for the detection of THC in marijuana. However, DNA analysis seems to be limited when DNA from heat-treated materials were analyzed.