There are many ways to administer medical and recreational cannabis, each with its own benefits and drawbacks. One common feature, however, is that only a certain (generally small) percentage of the consumed cannabinoid content, defined as "bioavailability", can be absorbed into the bloodstream with each method. This stems from the fact that cannabinoids are not water-soluble and, therefore, not readily compatible with the predominantly water-based human body. Water-soluble compounds such as ethanol, on the other hand, can be quickly and efficiently delivered to the bloodstream via a variety of alcoholic beverages, eliminating the need for other delivery methods. Wouldn't it be great if the same could be done with cannabis?
This is a second article in the series on the principles of formulating water-compatible cannabis extracts and isolates, also known as water-soluble CBD and THC. The first article showed multiple advantages of nanoemulsions over the other two water-compatible formulation classes: microemulsions and liposomes. Here I will demonstrate the importance of using a carrier oil in your cannabis extract or isolate nanoemulsion. I will also explain how to select the proper carrier oil among the available choices.
Industrial Sonomechanics is launching a series of blog posts dedicated to describing the main principles of developing water-compatible cannabis extract formulations, also known as water-soluble CBD and THC. As explained in our earlier blog post, since medical marijuana extracts are oils and, as such, not soluble in water, they have to be specially formulated in order to become water-compatible and acquire the appearance of being water-soluble. There are three formulation classes that can provide this property: microemulsions, liposomes and nanoemulsions.
For centuries, candles have been utilized for light, decoration, religious ceremonies and much more. The production of modern candles is a complex process, susceptible to several hurdles. Their main constituent, paraffin wax — which is desirable for its relatively low melting point of ~60°C  — experiences volatile changes in cost as it is a by-product of crude oil production . Additionally, during cooling, different parts of the jar candle solidify at different rates due to low heat conduction throughout the wax. This leads to uneven settling (referred to as surface undulation), which forms a cavity in the center of the candle and requires a post-process void-filling operation (see Figure 1).
Cannabinoids (CBD, THC, etc.) are hydrophobic (water-hating) oily substances and, as such, not water-soluble. They can, however, be formulated to be water-compatible and appear water-soluble.
The term "water-soluble CBD" has lately been extensively used throughout the medical cannabis industry. "Water-soluble" means able to homogeneously incorporate into water by separating into molecules or ions (dissolve like sugar, alcohol or salt). Oily substances, however, are repelled by water, which forces them to stay separate from it.
Medicinal uses of the cannabis plant (e.g., medical marijuana, hemp) have now been legalized in most US states. In addition to terpenoids and flavonoids, the plant may contain over 85 different types of therapeutically active compounds known as cannabinoids, the main two of which are tetrahydrocannabinol (THC) and cannabidiol (CBD). In recent years, medications based on concentrated cannabis extracts have become popular because they allow many routes of administration that are preferable to smoking the plant itself.
Oil-in-water emulsions with nano-sized droplets (nanoemulsions) are widely used in the pharmaceutical industry, for example, as an intravenous source of fatty acids when oral nutrition is disadvantageous or as bioactive compound carriers (e.g. drugs, vaccines). Pharmaceutical nanoemulsions can be administered by almost all available routes including parenteral, ocular, nasal, oral, topical, and even aerosolization to the lungs. There are currently over a dozen commercially available drugs encapsulated into nanoemulsions. Small oil droplet sizes and the associated stability of these products are critically important.
Combustion equipment (e.g., diesel engines, power boilers) emits significant amounts of hazardous gasses, such as Nitrous Oxides (NOx), hydrocarbons (HC), carbon monoxide (CO), carbon dioxide (CO2) as well as particulate matter (PM) and black smoke. Due to the widespread use of this equipment, the resulting damage to human health and the environment is tremendous. Adding 5 – 25% of water to the base fuel, such as diesel or kerosene, in the form of a very fine emulsion (nanoemulsion) significantly reduces these harmful emissions.
Are you able to make stable emulsions in the lab, but have trouble replicating the same result in the production environment? Scaling up an emulsification process is frequently even more challenging than succeeding at its lab optimization. In most cases, the post-scale-up loss of product stability is caused by the inability of industrial liquid processors to provide the same intensity of shear forces as was implemented during the research phase, which is why choosing the right production-scale equipment is fundamental.
Do you need to make a product that comprises a homogeneous mixture of oil and water? Is stability of this product a major concern? If so, you are not alone. One of the biggest challenges faced by product developers and process engineers in a wide variety of industries is achieving long-term stability of products based on combinations of oil and water.