It feels as though we’ve spent the past two decades referring to the cannabis industry as “fledgling, nascent, in its infancy”. Yet as the application of nanotechnology in the cannabis arena becomes more of a reality, it could be said the cannabis industry is flourishing into 21st-century adolescence.
What is nanotechnology?
Nanotechnology is the science by which structures can be characterised, designed or produced, measured according to a nanoscale. As the name implies it’s small, but comprehending how tiny takes some imagination.
Nanoscale translates to anything measuring 100 nanometres (nm) or less. Here is where the imagination comes in. A human hair measures around 80,000 – 100,000nm, so imagine something less than 1000 times the width of your hair and you are in the realm of nano measurements.
To make normal particles “shrink” to become nanoparticles, a range of different methods can be used. Not all of them are applicable to cannabinoids, being hydrophobic, water-repelling substances, specific techniques must be utilised.
Simply put, making nanocannabis involves the processes of sonification and emulsification. Ultrasonic waves break particles in cell walls and in doing so, make an oil-based solution soluble in aqueous substances. Whether using sonification or a different method, in making the nanosized water-soluble cannabinoids into an aqueous solution you end up with an emulsion.
These are not the only way to make nanoparticles. A range of different methods are used to create nanomedicines already on the market. Common pharmaceutical medications that utilise nanotechnology include medications used to lower cholesterol and modulate the immune system after organ transplants.
Nanotechnology has also been successfully used in the identification of certain cancers, specifically leukemia and breast cancers. Moving forwards, preclinical and early human trials are showing nanotechnology to be beneficial in increasing drug delivery for chemotherapy treatments.
By far the biggest benefit of the application of nanotechnology in cannabis is increased bioavailability. Bioavailability is the measure of active ingredients that makes it into the bloodstream and is a huge consideration, particularly in the application of medical cannabis.
Different delivery methods – ingestion, inhalation and topical – provide different levels of bioavailability. Inhalation delivers cannabinoids into the bloodstream effectively and quickly, yet has a plethora of adverse health effects associated with it. Ingesting cannabis products leaves cannabinoids to the mercy of the gastrointestinal tract, where what’s called “first-pass metabolism” slows absorption, with the liver filtering out or modifying many of the cannabinoids. This can lead to as little as 4% bioavailability.
Topical medical cannabis products seem ideal to relieve local pain and inflammation from conditions like arthritis however, and the amount of cannabinoids absorbed through the skin is sub-optimal. Topical applications do provide relief for many, yet efficacy could be much improved with increased bioavailability.
By utilising nanotechnology, cannabinoids are made more compatible for absorption via the skin and mucous membranes in the mouth and gastrointestinal tract – which facilitates a fast onset of therapeutic action, in some instances within mere minutes, instead of hours.
Moreover, having an increased bioavailability provides the opportunity to be more precise with dosing. So far information indicates nanocannabinoid formulations can offer as much as 50-100% bioavailability. Such knowledge could reduce some of the uncertainty that comes with oral or gastrointestinal administration.
Benefits of nanotechnology go beyond bioavailability: versatility is one of the paramount reasons nanocannabinoids are so exciting. In a medical setting, it could allow for cannabinoids to be dispersed in any number of mediums such as drinks, creams, and wafers, dissolving concerns around delivery methods for patients that may have difficulty swallowing conventional capsules, oils or tinctures.
By making cannabinoids that are usually oil-soluble able to be mixed in water or other aqueous solutions, prospects of creating potent and palatable formulations open up. As mentioned, nanocannabinoids can be used in liquid formulations and topicals, and beyond that, intranasal and buccal applications already available could have their bioavailability and therefore therapeutic action increased as much as four-fold with nanotechnology.
Experiments are being conducted using the nasal cavity to direct nanocannabis formulations straight to the brain, as well as eye drops to treat local pain or inflammation. These concepts are still far away from being available to patients and there are still concerns to address, but it does show the potential for technology to deliver benefits in this rapidly evolving industry.
As with all things, there is a shadow side to these wonderfully tiny technologies. As particles are so small, there is a significant chance they can pass the blood-brain barrier. This important filter acts as a gatekeeper for the brain, preventing any unwanted material from coming into the brain cavity. Because of their size, certain nanoparticles may be able to navigate this gatekeeper and enter the brain. As this is such a new application, we have very little understanding of how nanotech therapeutics act on the brain or their long-term safety.
Additionally, solvents that are used have the potential to accumulate in body tissues, possibly causing negative effects down the line. While this risk is not unique to nanocannabis, pharmaceuticals and other nanotech medicines also contain solvents and excipients that may increase toxic load, and the lack of research into the adverse effects has caused pause among many in the industry and medical landscape.
The jury is still out on this one. Fortunately, there are plenty of curious entrepreneurs and dedicated scientists willing to find out the answers for us, and as it stands current tests and procedures are able to predict risk factors, ensuring the safety of patients.
As the pharmacokinetics of nanomedicines are uncovered in the wider clinical research field, the medical cannabis industry will be able to draw upon this knowledge to advance and improve the therapeutic action and safety profile of nanocannabis formulations.
While many cannabis nano-possibilities are still conceptual and untested on humans, with the advent of novel applications in an already novel industry, it certainly feels like cannabis is growing up.
By Jessica Kindynis