Purification of Substances Using CO2 Sub-and Super-Critical Fluid Chromatography

Technology

Fluid chromatography occurs in two phases, a stationary phase, and a mobile phase. This technology is applicable to the mobile phase in which a mixture of compounds is applied to a chromatographic column. Each of the substances passing through the column separate from the mixture at varying points in time. This separation allows for the collection of the desired compounds and disposal of unwanted compounds. When applying this technique to pharmaceuticals for human consumption, separating and disposing unwanted compounds is essential as these could be toxic. This invention aims to eliminate the need for toxic co-solvents by removing them while deriving natural products from cannabis. This technology proposes a method of supercritical fluid chromatography employing sub- or super-critical sCO2. This invention proposes the use of sCO2 in the mobile phase of chromatography instead of the typical polar co-solvents that could be toxic for human consumption. Given the known non-polarity of cannabis compounds, a polar solvent is typically employed to increase the viscosity of the mixture. This invention proposes utilizing sCO2 at altered temperatures and pressures eliminating the need for toxic, polar co-solvents (e.g., methanol and ethanol) and for extra purification steps to remove these co-solvents. This technology will reduce the time, risk, and cost associated with obtaining cannabis-derived compounds for pharmaceutical products.  

Problem Addressed

This technology eliminates the use of potentially toxic polar co-solvents, such as methanol and ethanol, in the mobile phase of fluid chromatography.  

• These co-solvents are used to enhance the solubility of cannabis-derived products but are toxic to humans and require extra purification steps for removal. 

• These products typically are removed by adding heat, which can denature the cannabis compounds and reduce the quality of the product. 

• This technique facilitates the isolation and purification of naturally derived compounds from a mixture. 

• Methods for removing co-solvents require larger time and monetary investments. Replacing co-solvents with sub- or super-critical sCO2 eliminates extra purification steps. 

Advantages

• Reduces consumer cost and availability for use as pharmaceuticals.  

• Reduces risk of product toxicity by eliminating processes that include contaminants that would be harmful for human health. 

• Reduces cost and time commitment necessary for isolating cannabis compounds.  

• Expands upon previous knowledge of the ability of sCO2 to replace liquid polar co-solvents in the mobile phase of fluid chromatography.