What Is Water-Soluble CBD?

by Claudia S. Copeland, PhD

Cannabidiol (CBD) — one of the many cannabinoids found in the hemp plant — is among the most sought-after products for enhanced psychological and physical well-being. Unfortunately, it is also fat-soluble. This means that it dissolves well in oil but poorly in water. Not a problem if you are just looking for a quality like flavor, but if you are looking for a wellness effect like CBD’s well-documented positive effects on the endocannabinoid system, it is a big problem. If a substance is not water-soluble, it will be poorly absorbed with low bioavailability. (In other words, only a small percentage will end up reaching its physiological target resulting in low potency.) Fortunately, this problem has a solution — using nanotechnology to create functionally water-soluble CBD.

What Is Water Solubility?

Before exploring nanoemulsion technology, let’s take a step back and look at what water solubility actually is and why it’s important. Solubility is all about the stickiness conferred by electrical charge which occurs when positively-charged protons are not in equal balance with their corresponding negatively-charged electrons. Nonpolar molecules have perfectly balanced protons and electrons throughout the molecule. They have no net charge anywhere (whole or partial). 

In between the two extremes of nonpolar and ionic compounds, lay the polar molecules. Polar molecules do not have an overall charge, but they have partial charges in different parts of the molecule. Water is an example of a polar molecule. It does not have a charge overall, but it does have one end — the oxygen in H2O — where electrons spend more time bunching up there and giving this end a partial negative charge. This leaves the hydrogen ends partially positively charged.

The effect this has on solubility is that the negative end of a polar molecule will form a weak bond with water’s positive end and vice versa. Opposites attract which causes the charged and polar molecules to end up “sticking” together. Nonpolar molecules (such as oils, fat-soluble vitamins like vitamin D and fat-soluble wellness products unlike CBD) end up pushed out of the way — they do not “stick” to the polar molecules and become isolated from them. (Oil-and-vinegar salad dressing is a prime example of this —you can shake the bottle and they will mix together, but the nonpolar oil layer soon forms bubbles which eventually join and form a separate layer that is isolated from the polar vinegar.)

Why Is Water Solubility Important?

So, why worry about water solubility? Why not just dissolve the CBD in oil? The answer is that our bodies are made of water in a polar environment, and CBD isolated in oil bubbles within the watery environment of the gastrointestinal (GI) tract will not be well-absorbed through the walls of the intestines. Although the body does have physiological systems in place for absorbing fats, a number of biochemical processes interfere with absorption and bioavailability of fat-soluble molecules. Some CBD will reach its target tissue if it’s a pure CBD oil, but it won’t be absorbed anywhere near its optimal potential — only about 9 percent will actually get through. In order for a substance to be maximally bioavailable — able to enter the bloodstream and eventually reach its physiological target — it must first be well-absorbed. In order to be well-absorbed from the water-based interior of the human GI tract, it must be water soluble

How to Get Fat-soluble Compounds to Dissolve in Water

Getting fat-soluble (also known as hydrophobic — water-fearing —or lipophilic — fat-loving) compounds into a water-soluble form is a major challenge that must be solved in order to maximize bioavailability. This has, in fact, been understood by pharmacists as an important challenge for more than a century. The key is finding a way to coat the fat-soluble compound in a group of molecules that are polar on one end and nonpolar on the other. The nonpolar end binds to the fat-soluble substance while the polar end binds to water. The combined nonpolar molecules and their polar carriers form colloids — nanoparticles that can evenly disperse in a water-based solution. This process is called emulsification. Traditional emulsions have been around for some time, but newer methods are being developed to maximize absorption of fat-soluble drugs and wellness compounds.

Nanotechnology for Lipophilic Compounds Like CBD

The latest tool being used for this purpose is nanotechnology. These approaches are being developed for the improved bioavailability of pharmaceuticals, “smart-foods” and fat-soluble nutrients.  Nanoemulsions are systems that carry fat-soluble vitamins or fat-soluble substances like CBD. Suspended in a nanoemulsion carrier, CBD becomes, for all practical and biological purposes, water soluble. Optimizing these systems and their component nano carriers for CBD are hot topics in ongoing cannabinoid research.

Nanoemulsion technology is used for all of Curatio’s CBD blends. This technology can effectively make the highly hydrophobic full-spectrum CBD offered by Curatio into a hydrophilic one. CBD in a nanoemulsion carrier acts like water-soluble CBD. Therefore, a nano CBD solution provides more bioavailability, and that means optimal CBD-conferred wellness effects for you.

Dr. C.S. Copeland holds a Ph.D. in molecular and cellular biology from Tulane University and a B.A. in neuropsychology from the University of California at San Diego. She has been a scientific writer, editor and translator since 2008.


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