This morning, we continued shadowing Sean as he analyzed the samples of oven-dried hemp flowers and CBD oil. He showed us the collected data displayed on his computer and talked us through the process of creating a report for the concentrations and percentages by mass of the components of each sample. We then went back to the lab to clean the two mass spectrometers, a procedure repeated on a weekly basis. After taking apart each mass spectrometer, Sean wiped down the larger parts, first with pure H2O and then with isopropanol. He also placed the smaller metal parts used to conduct ions into a graduated cylinder filled with water; this graduated cylinder was then moved into a sonicator, a machine that applies ultrasonic frequencies that cause the parts to vibrate and dislodge any trapped ions or impurities.
In the afternoon, Krystle showed us how she performs screening tests for urine samples to determine whether they contain certain drugs and ensure that they have not been tampered with or diluted. The Enzyme Multiplied Immunoassay Technique (EMIT) detects enzyme activity in a sample in order to measure the concentration of drugs. Point of Care Testing (POCT) cups with strips of nitrocellulose membrane lining their walls are filled with urine samples; the number of lines appearing on the strips indicates whether a sample tests positive or negative for each drug. Krystle also emphasized the importance of conducting confirmation testing using HPLC: immunoassay testing cannot differentiate between compounds with similar molecular structures, such as CBD and THC, while confirmation testing can more accurately determine the compounds present.
