Rapid electrochemical lateral flow device for the detection of Δ9-tetrahydrocannabinol.

Cannabis is a plant that is harmful and beneficial because it contains more than 400 bioactive compounds, and the main compounds are Δ9 tetrahydrocannabinol (THC) and cannabidiol (CBD). Currently, cannabis extracts are used in medicine, but the amount of THC as a main psychoactive component is strictly regulated. Therefore, the ability to rapidly and accurately detect THC is important. Herein, we developed a sensitive electrochemical method combining a rapid lateral flow assay (LFA) to detect THC rapidly. An electrochemical LFA device was constructed by attaching a screen-printed electrode inside a lateral-flow device to exploit the remarkable binding of THC to the cannabinoid type 2 (CB2) receptor in the test zone. The ferrocene carboxylic acid attached to the monoclonal THC antibody acts as an electroactive species when it binds to the THC in the sample before it flows continuously to the CB2 receptor region on the electrode. Under optimal conditions, the detection time is within 6 min and the devise shows excellent performance with a detection limit of 1.30 ng/mL. Additionally, the device could be applied to detect THC in hemp extract samples. The results obtained from this sensor are similar to the standard method (HPLC) for detecting THC. Therefore, this proposed device is useful as an alternative device for the on-site determination of THC because it is inexpensive, portable, and exhibits high sensitivity.

Determination of the relative percentage distribution of THCA and Δ(9)-THC in herbal cannabis seized in Austria - Impact of different storage temperatures on stability.

Cannabis is globally by far the most widespread illicit drug of abuse. Especially since its legalization in some of the US, controversies about the legal status of cannabis for recreational and medical use have come up. Δ(9)-Tetrahydrocannabinol (Δ(9)-THC), which is the major active ingredient in cannabis products, is mainly responsible for the psychoactive effects. Its inactive biosynthetic precursor tetrahydrocannabinolic acid (THCA) is present in different quantities in fresh and undried cannabis plants. Under influence of drying, temperature and UV exposure it decomposes to Δ(9)-THC. In this study, a quantification of Δ(9)-THC and THCA was carried out to check the stability of cannabis samples. The determination of the degradation of THCA to Δ(9)-THC in 29 cannabis products seized in Austria was monitored by HPLC-UV. Mobile phase consisted of a 25mM triethylammoniumphosphate buffer (pH 3.0) and acetonitrile (36:64). A common LiChrospher(®) 100 RP-18 column was utilized as stationary phase. To check the influence of low as well as high temperature on the degradation process of the cannabinoid THCA to Δ(9)-THC, samples were stored in a freezer or in a drying cabinet for a specified time period. It was shown successfully that high storage temperatures led to a more rapid and complete decomposition of THCA to Δ(9)-THC while at low temperatures only slight or no changes of the percentage distribution were determined.

Determination of lipoic acid in dietary supplement preparations by capillary electrophoresis.

The present study deals with the development of a method for the quantitative determination of lipoic acid in a dietary supplement preparation. A rapid capillary electrophoretic method is developed using UV detection at 208 nm. Although lipoic acid is only weakly UV-absorbing, at this wavelength it could be detected with sufficient sensitivity with an LOD and LOQ of 0.8 and 2.5 microg/ml, respectively. Analysis time was less than 9 min. The compound was extracted from tablets with a recovery of 98.3% and a precision of 2.8% RSD.