Cannabis Oil / CBD Nanoemulsion by Ultrasonics
Making clear, translucent cannabis nanoemulsions is a real challenge. Ultrasonic emulsifiers are a highly efficient technique to produce clear, long-time stable nanoemulsion encapsulating cannabinoids. Ultrasonically nano-emulsified CBD, CBG or THC have a significantly higher bioavailability.
Make CBD Nano-Emulsions using an Ultrasonic Probe
Ultrasonic cavitation is a very effective emulsification method to prepare superior emulsions in the nano range. The sonication of emulsions with turbidities (micro-emulsions, approx. 150 to 100nm) makes them translucent or clear and transparent, because it reduces the CBD droplet size to diminutive droplets in the range of approx. 10nm. This increases the emulsion stability significantly. Ultrasonically produced emulsions are often self-stable without addition of an emulsifier or surfactant.
For cannabis oil, nano emulsification improves cannabinoids absorption and bioavailability, thereby producing a more profound effect when orally administered. Therefore, when compared to conventional CBD formulations, nanoemulsions allow for a lower cannabis product dosage and achieve the same effects.
Cannabis oil emulsions are suspensions of micron-size or nano-size cannabinoids for cannabis-, hemp-, THC- or CBD-based products such as tinctures, capsules, lotions, and e-cigarette vape cartridges. Cannabinoids such as THC, CBD etc. are lipophilic (= hydrophobic). Therefore they require intense shear to disperse the cannabinoid in water-based formulations. Cannabinoids are not soluble in water, but they show a good solubility in non-polar solvents such as oils and fats. It requires a suitable emulsification technique to overcome the immiscibility of cannabinoids in water. Intense ultrasonic cavitation is well-known and well-established technique to produce fine-sized, stable emulsions (o/w, w/o, w/o/w, o/w/o, micro- and nanoemulsions).
Oil: Vegetable oils such as olive oil, coconut oil or MCT oil assist the absorption of the active substances of cannabis into the digestive system. Cannabinoids such as CBD and THC can hardly be absorbed without oil or fat. To achieve an optimal absorption, cannabis extracts are mostly emulsified into oil and then further processed into an emulsion.
Emulsifier: Lecithin, which is available in powder, granules and liquid form, is an emulsifier, which is suitable for food and medical products. For cannabis oil emulsions, lecithin is one of the most common emulsifiers. Other emulsifiers, which give good effects are gum arabic or starch-based emulsifiers.
How to Prepare a Cannabis Emulsion with Sonication
In order to prepare stable CBD nano-emulsions, a mix of Polysorbate 80 and Lecithin works very well. There is no need to buy overpriced pre-mixes as both additives are easily available in food-grade quality.
- Polysorbate 80: also known as Alkest TW 80, Scattics, Canarcel, Poegasorb 80, Montanox 80, Tween 80
- Lecitin: Lipoid is a manufacturer of high-quality lecithin.
Recipes for the Formulation of CBD Nanoemulsions
For 2wt% CDB nanoemulsion (oil in water) use: 2wt% CBD oil, 2wt% Polysorbate 80, 1wt% Lecithin, 95wt% water
For 5wt% CDB nanoemulsion (oil in water) use: 5wt% CBD oil, 3.3wt% Polysorbate 80, 1.7wt% Lecithin, 90wt% water
Ultrasonic energy requirement: approx. 300 to 400Ws/g of sonication energy at amplitudes of 40 to 70 micron. The ultrasonicators UP200Ht or UP400St are suitable emulsifying devices for up to 5L per batch.
Step-by-Step Protocol for Making an Ultrasonic CBD Nanoemulsion:
- Oil Mixture: For the preparation, premix approx. 10mL of cannabis oil (e.g. CBD oil, has oil BHO) with 40mL of olive oil!
- Oil-in-water-Nanoemulsion: In order to prepare the cannabis oil emulsion, take a beaker with approx. 100mL of water. As emulsifier, add approx. 10-15 grams of liquid soy lecithin. The water should have room-temperature. Place the water beaker in a water bath in order to control temperature during sonication. Immerse the sonotrode of the UP400St into the beaker with water. For sonication, set to 50% amplitude. Slowly pour the cannabis oil/olive oil mix into the 100mL of room-temperature water while sonicating the water to form an nanoemulsion. In order to improve a better emulsion, add the oil premix into the water right under the sonotrode using an eyedropper or syringe.
For larger scale setups using a flow cell, the Hielscher MultiPhaseCavitator InsertMPC48 is used to inject the CBD oil directly into the area of ultrasound cavitation beneath the ultrasonic sonotrode. The MultiPhaseCavitator InsertMPC48 is used for ultrasonic inline production of nanoemulsions and assures the uniform nano-emulsification of CBD oil in water mixtures.
The Role of Carrier Oils for Ultrasonic Nanoemulsions
Carrier oils are an important component in the preparation of ultrasonic CBD nanoemulsions.
To create a stable nanoemulsion, the CBD oil needs to be dispersed uniformly throughout the aqueous phase. This is where carrier oils come in. Carrier oils are typically lighter, less viscous oils that are more miscible with water than CBD oil. They are used to dilute the CBD oil and make it easier to disperse in the aqueous phase.
Carrier oils also play a role in the stability of the nanoemulsion. The type of carrier oil used can affect the droplet size and stability of the nanoemulsion. For example, certain oils may be better at stabilizing small droplets, while others may be better at preventing droplet coalescence over time.
In addition to their functional role, carrier oils can also have an impact on the sensory properties of the final product. They can affect the texture, color, and aroma of the nanoemulsion.
Overall, carrier oils are an important component in the preparation of ultrasonic CBD nanoemulsions. They help to disperse the CBD oil in the aqueous phase, stabilize the nanoemulsion, and can impact the sensory properties of the final product.
List of Good Carrier Oils for Ultrasonic CBD Nanoemulsions
In our example above, we use olive oil as a carrier oil for the ultrasonically prepared cannabis oil nanoemulsion. Besides olive oil there are several other options that are commonly used as well. The best carrier oil for CBD nanoemulsions can depend on a few factors, such as the desired droplet size, stability, and sensory properties of the final product. Here are some common carrier oils used for CBD nanoemulsions and some of their properties:
- MCT (medium-chain triglyceride) oil: MCT oil is a light, colorless, and flavorless oil that is derived from coconut oil. It is a popular choice for CBD nanoemulsions because it is highly stable, has a long shelf life, and can help to produce small droplets.
- Sunflower oil: Sunflower oil is a neutral-tasting oil that is high in unsaturated fatty acids. It is a good choice for CBD nanoemulsions because it can help to produce small droplets and has a high oxidative stability.
- Hempseed oil: Hempseed oil is a popular carrier oil for CBD products because it is rich in omega-3 and omega-6 fatty acids. It can be used as a carrier oil for CBD nanoemulsions, but it may not be as stable as other oils and may produce larger droplets.
- Grapeseed oil: Grapeseed oil is a light, flavorless oil that is high in unsaturated fatty acids. It is a good choice for CBD nanoemulsions because it can help to produce small droplets and has a high oxidative stability.
Ultimately, the choice of carrier oil will depend on the specific requirements of the product and the desired sensory properties. It’s important to note that the choice of emulsifier and processing conditions (such as the energy input during ultrasonication) can also have a significant impact on the properties of the final nanoemulsion.
Liposomal Emulsions of CBD
Ultrasonification is the preffered method to produce liposomal CDB or liposomal THC as pharmaceutical and cosmetic vesicles. Liposomes are lipid-based nanocarriers for active drug components, which improve the bioavailability and therapeutic effects of the active substances such as CBD or THC. Since cannabinoids are really delicate molecules, they are prone to degradation by oxidization as well as to degradation by different enzymes. Nano-encapsulation of CBD or THC in liposomes, prevents the degradation of the cannabinoids. Sonication can effectively encapsulate the cannabinoids into liposomes.
Click here to read more about liposomal encapsulation of active substances!
THC/CBD Nanoemulsion Stability
In order to produce long-term stable oil-in-water (o/w) nanoemulsions, it is necessary to use a suitable surfactant or to form liposomes that encapsulate the lipophilic bioactive compounds into a carrier oil. For cannabis oil, the carrier oil should have food quality and it should not interfere with appearance, taste, or stability of the final product. Coconut oil (MCT) and olive oil are good carrier oils for cannabinoids. Carrier oils are a very important factor to create a physicochemically stable emulsion since they may help to prevent the emulsion against Ostwald ripening. The Ostwald ripening is the driving force which destabilizes an emulsion by droplet coarsening. Long chain triglyceride nanoemulsions are long-term stable against Ostwald ripening. Olive oil and coconut oil contain long chain triglycerides, so that both, olive and coconut oil are a suitable carrier oils to THC or CBD.
Ultrasonic Equipment for Nanoemulsification
You can produce a CBD nanoemulsion in batch or continuous mode using an ultrasonic emulsification machine. Hielscher ultrasonic homogenizers are powerful emulsifiers to produce stable CBD nano-emulsions. The ultrasonic production of cannabis oil emulsions (o/w) is an easy and fast procedure, which convinces by optimum results.
Hielscher Ultrasonics is the leading supplier for powerful and reliable ultrasonic systems. It covers the full range from lab and bench-top devices to full industrial machines for the processing of large volumes under demanding conditions. Common applications or Hielscher ultrasonic machines include emulsification, homogenization and extraction for food and beverage as well as in the pharmaceutical or cosmetic industry.
|Emulsion Batch Volume||Emulsion Flow Rate||Recommended Devices|
|0.5 to 1.5mL||n.a.||VialTweeter|
|1 to 500mL||10 to 200mL/min||UP100H|
|10 to 2000mL||20 to 400mL/min||UP200Ht, UP400St|
|0.1 to 20L||0.2 to 4L/min||UIP2000hdT|
|10 to 100L||2 to 10L/min||UIP4000|
|n.a.||10 to 100L/min||UIP16000|
|n.a.||larger||cluster of UIP16000|
Ultrasonic extraction is well known and a long-term established process to extract valuable compounds from botanicals. Therefore, sonification is the ideal technique to produce high-quality CBD oils. By precisely controllable ultrasonic cavitation, plant cells are perforated and the solvent is pushed into the cell, where it absorbs intracellular compounds such as cannabinoids, terpenes, flavonoids etc.
Read more about extraction from cannabis!
Facts Worth Knowing
THC and CBD Nanoemulsions
Nanoemulsions are also known as miniemulsion or submicron emulsion. Nanoemulsions are emulsions with a droplet size between 20 and 500nm. A nanoemulsion is a thermodynamically stable isotropic system, which consists in two immiscible liquids (e.g. oil and water). One of the two immiscible liquids is dispersed very finely into the second phase in order to form a single phase. The addition of emulsifiers, e.g. surfactants and co-surfactants stabilize the emulsions by preventing the coalescence of the droplets. The size and shape of particles/droplets dispersed in the continuous phase defines the main difference between an emulsion and a nanoemulsion. Ostwald ripening is the major destabilization mechanism in THC or CBD nanoemulsions. Ostwald ripening is a diffusion degradation process, which means that an inhomogeneous structure such as an emulsion changes over time. The emulsion droplets increase over time as the smaller droplets dissolve and redeposit their material onto the larger droplets. The oil type has major influence on the intensity and rate of Ostwald ripening. This means that the choice of a suitable oil can affect the emulsion stability significantly. Nanoemulsions show an improved delivery of active ingredients (e.g. drugs).
About Butane Hash Oil (BHO)
Hash oil is produced by solvent extraction, e.g. ultrasonic extraction or ultrasonically-assisted supercritical C02 extraction. For the production of hash oil, preferably dry, decarboxylated plant material is used. The following liquids are frequently used solvents for hash oil extraction: ethanol, chloroform, dichloromethane, petroleum ether, naphtha, benzene, butane, methanol, isopropanol, and olive oil. Non-polar solvents such as benzene, chloroform and petroleum ether, cannot extract the water-soluble constituents of marijuana or hashish. This helps to obtain a more potent hash oil. The extraction of cannabis extracts with non-polar solvents produces a better taste product than the extraction with polar solvents. The washing of extracts with alkali can improve the odor and taste of the hash oil.
Store hash oil in an airtight container and protected it from light exposure. Exposure to air, warmth and light, causes the oil to lose its taste and psychoactivity due to aging. The addition antioxidants to hash oil formulation can reduce this negative effect.
There are at least 113 identified types of cannabinoids in cannabis. Cannabinoids are active phytochemical substances with psychoactive and/or medical effects. THC or tetrahydrocannabinol is the primary psychoactive compound in cannabis. CBD or cannabidiol is another important ingredient with therapeutic effects. Cannabinoids are lipophilic and potentially acid-labile compounds. Cannabinoids are insoluble in water, but they are very soluble in non-polar solvents (e.g. fat and oil). To improve the digestion of cannabinoids, cannabis extracts are mixed into carrier oils and then ultrasonically processed into nano-emulsions.