Selective and Rapid Water Determination in Cannabis

Reproducible Results in Less than 30 Minutes

The determination of the water content in cannabis is of great importance for the qualitative assessment of the active components (THC, CBD) as well as its storage stability. Karl Fischer titration offers a selective and reliable alternative to the drying method.

Compared to the reference method of national and international pharmacopoeias, which require a determination via the loss on drying over 24 hours, the Karl Fischer method provides a selective and reproducible result in less than 30 minutes with a significantly smaller sample quantity.

The interest on Cannabis and its products for medical purposes has increased over the past years. Hemp cultivation is an important component of the European Green Deal, in which the European Union has set itself the goal of creating “the transition to a modern, resourceefficient and competitive economy” _[2]. As a result, the area available for hemp cultivation (industrial hemp) in the EU increased from around 20k ha in 2015 to around 35k ha in 2019. This corresponds to an increase of 75 % _[1].

Advantages of the Karl Fischer oven method

• Selective results, only water is determined
• Fast results in less than 30 minutes
• Small sample quantities for fewer sample losses
• Reproducible results
• Simple sample handling due to direct weighing into a glass vial

The results presented in our white paper were obtained using SI Analytics® KF Titrators and KF Headspace Oven from Xylem using industrial hemp containing CBD.

_{[1] Hemp production in the EU, https://agriculture.ec.europa.eu/farming/crop-productions-and-plant-based-products/hemp_en, retrieved 12.2023}

_{[2] The European Green Deal, https://commission.europa.eu/strategy-and-policy/priorities-2019-2024/european-green-deal_en, retrieved 12.2023}