Ultrasonics and Cannabis
Cannabis extracts thc are hydrophobic water soluble molecules. in order to overcome the immiscibility of cannabinoids infuse edibles beverages creams and other infused products a proper method emulsification is needed. ultrasonic processors have been used pharmaceuticals industries for making stable emulsions over half century.
Through the powerful forces created by ultrasonic cavitation, Sonicators have the ability to achieve nanoparticle sizes which other emulsification technology cannot. With sufficient processing, particle sizes under 100 nm are often achievable (see particle size data). What this smaller particle size means for your cannabis infused products is:
- more translucency / clearer, less cloudy appearance
- increased bioavailability / better absorption
- more accurate dosing / more uniform concentrations
Oil/Water Cannabis Nanoemulsions are emulsions with small droplet size which have several attractive properties for cannabinoid formulations including a higher degree of clarity, stability and low viscosity.
A variety of cannabis inputs, including distillate, isolate and full/broad-spectrum oils can be processed to form nanoemulsions.
Sonicators can reduce particle size of an API (Active Pharmaceutical Ingredient) to 30-90nm (depending on the formulation). Sonication creates a concentrated nanoemulsified solution to accurately infuse their final product (e.g. beverages, edibles, etc.) with a known concentration of API. For cannabis applications, concentrate formulations typically contain 10-50mg/mL API load.
For a more thorough description of a nanoemulsion, to learn about surfactants/emulsifiers and how sonication can help, please review our Nanoemulsion Workflow Document.
Beverages infused with a stable nanoemulsion offer:
- Enhanced absorption of the active ingredient
- Rapid onset of active ingredient’s effects
- Optical clarity and homogenous appearance
- Reduced degradation of the active ingredient
Nanoemulsions can also be consumed directly in what is commonly referred to as a tincture. Viewed as a flexible means of consuming cannabinoids, tinctures are a popular product format for nanoemulsions loaded with cannabinoids. They can be flavored or unflavored, and loaded up to typically 10-50mg of active ingredient per gram of nanoemulsion (approximately 50mg/mL); though you can achieve higher loads at the expense of particle size.
Lotions and serums can also benefit from the use of nanoemulsions, as they can enhance the delivery of active ingredients through the skin. While more difficult to conduct stability tests on due to the opaque nature of most lotions, a stable nanoemulsion has potential to dramatically improve a consumer’s ability to absorb active ingredients in a nanoemulsion format. Rapid onset, enhanced absorption and reduced degradation of the active ingredient are all reasons to consider using nanoemulsion-infused topicals.
Sonicators, together with an effective surfactant system, allow you to drive the active ingredient’s average particle size down to well under 50 nanometers, maximizing absorption in your topical product.
Effective nanoemulsions require a mixture of water, your active ingredient (CBD or THC) and a surfactant formulation. Many talented chemists are capable of developing their own formulation. For those who do not have the time or expertise to engage in their own R&D/formulation, a high quality surfactant/stabilizer system is readily available.
Qsonica recommends a surfactant system from Cannasol Technologies.
Cannasol Technologies www.cannasoltechnologies.com
Publications and Protocols
Tips & Info for Creating Cannabis Nanoemulsions
- Vessel Shape and Size - A narrow vessel is preferable to a wide vessel. The ultrasonic energy is generated from the tip and is directed downward. As a sample is processed the liquid is pushed down and away in all directions. If the vessel is too wide it will not mix effectively and some sample will remain untreated at the periphery. Twice the volume in a narrow vessel takes a shorter time to process than the same volume in a wider vessel. In addition, the probe should never touch the sides or bottom of a vessel.
- Viscosity - Ultrasonic systems, especially larger ultrasonic systems, work best with low-viscosity liquids. If you are manufacturing a cannabinoid-infused cream or other viscous infusion, it is recommended that you make a low-viscosity liquid concentrate and then mix the concentrate into your final product. Your mixture may be heated slightly to reduce viscosity for processing, but be mindful of the temperature so you do not degrade the cannabinoids.
- Surfactants / Stabilizers - Particle size reduction will greatly improve the performance and stability of your product, but particle size reduction alone will not make an insoluble molecule soluble. To maintain a long shelf life, a surfactant or stabilizer must be used. These are amphiphilic compounds, meaning they have hydrophobic and hydrophilic groups (areas that are attracted to water and repelled by water). These can change the chemistry of your mixture to prevent reagglomeration and improve the duration your cannabinoid nanoemulsion remains stable.
- Heat - If emulsifying in batch, be sure to monitor the temperature of your mixture such as not to degrade the cannabinoids by overheating. Always homogenize on pulse mode when processing in batch. When homogenizing in-line, ensure you are cooling the jacketed vessel with a suitable recirculating chiller.
- Process Conditions - If you are not achieving the desired nanoparticle sizes and are processing in batch, you may be processing for too short of a time or in too large of a volume. If you are not achieving the desired nanoparticle sizes with a flow cell configuration, you may need to decrease the flow rate of your process stream. In either configuration, increasing the amplitude will also help if not already at the maximum.
- For general best practices, see Best Practices for Ultrasonic Homogenization.
Ultrasonic-Assisted Cannabinoid Extraction
Ultrasonic homogenizers are also used to increase the efficiency of small-scale cannabinoid extraction while decreasing the time required to perform extraction, leading to more yield per pound of flower with less waiting. You can still use ethanol for the extraction, only instead of waiting overnight, you extract on the spot with a Sonicator!
Please note that the largest Sonicators have a maximum batch processing volume of approximately 50 liters, so ultrasonic-assisted cannabinoid extraction is only suitable for batches with total volume (flower + ethanol) 50 liters or less.
The flower should be ground up as much as possible. Add 5 to 10 volumes of solvent for every volume of flower. Process for roughly 10 - 20 minutes at 70% amplitude, ensuring to keep the vessel cold. Strain first through a mesh sieve to remove large particles of flower, then through a micropore filter (i.e. filter paper) to remove remaining solids. Remove the solvent with rotary evaporation.
Shorter processing durations will yield comparatively more terpenes, while longer processing durations will yield comparatively more THC / CBD.