US: Scientists Develop Method To Detect Marijuana Amounts In Edibles


A group of scientists say they have invented a new technique for measuring levels of tetrahydrocannibinol (THC) and cannabidiol (CBD) in food made with marijuana, according to a press release from The American Chemical Society (ACS).

Most edibles are analyzed using a high performance liquid chromatograph, or HPLC, but the readings are notoriously inaccurate.

"These machines were never designed for you to inject a cookie into them," Jahan Marcu, director of research and development at Green Standard Diagnostics Inc. and a senior scientist at Americans for Safe Access said. "The sugars, starches and fats will wreak havoc on HPLC equipment. They can really muck up the works and lead to inaccurate results."

Marcu, along with others working with the ACS, developed a new method of testing that breaks down the edible into distinct particles that are better read by the HPLC.

Scientists first place samples of food laced with cannabis into a cryo-mill with dry ice or liquid nitrogen. Then they add abrasive diatomaceous earth and grind the mixture to create a homogenous sample.

Using a technique called flash chromatography, the scientists are able to separate the various chemical components of the sample which allows them to inject liquid containing only the cannabinoids into an HPLC for analysis.

The researchers say this new process could yield “far more accurate and reliable measurements of THC and/or CBD levels in an edible product than was previously possible.” It has already been found to accurately measure cannabis content in gummy bears, brownies, cookies and certain topical lotions.

"Producers of cannabis edibles complain that if they send off their product to three different labs for analysis, they get three different results," says Melissa Wilcox of Grace Discovery Sciences. "The point of our work is to create a solid method that will accurately and reliably measure the cannabis content in these products."