Solvent extraction in industrial pharmacy is utilized as a means of purifying and separating the drugs from the byproducts required for their synthesis. Solvent extraction involves the target compound, the solid or liquid they are contained in, and a new solvent chosen to remove them from the starting material.
In this blog post, we’ll take a closer look at what exactly solvent extraction in pharmacy is, how to choose a solvent, and where you can find solvents for your industrial extraction needs.
Why Solvent Choice Matters
When choosing the appropriate materials for your pharmacy extraction, it is important to consider:
Volatility
Make sure your solvent is stable enough to remain in the liquid phase for long enough to perform the process.
Polarity
“Like Dissolves Like”- you want a solvent with similar polarity to what you are trying to dissolve, in order to make sure the process will have the proper solubility.
Acidity
If you are performing an acid-base extraction, the pH of the solvent will affect the amount of compound that can be transferred.
All these qualities are specific to each compound being used, but also to the liquid or solid containing the target compound. It is imperative that these factors are kept in mind while selecting the appropriate materials.
Solvents Used in Extractions for Industrial Pharmacy
Depending on the starting material you are trying to extract from, different solvents will work more efficiently. Here is a list of some of the common categories of organic compounds that can be utilized:
- Chlorinated compounds (e.g., dichloromethane, chloroform, methylene chloride)
- Alcohols (e.g., methanol, ethanol)
- Ketones (e.g., acetone)
- Ethers (e.g., diethyl ether)
- Esters (e.g., ethyl acetate)
- Supercritical fluids (e.g., carbon dioxide)
These chemicals are all commonly used in industrial pharmaceutical settings, in both liquid-liquid and liquid-solid extractions.
Example of Industrial Pharmacy Extraction and Solvent Choice: Ibuprofen
All industrial-scale production of medicines, whether synthetic or naturally derived, relies on solvent extraction to purify or remove unwanted byproducts from the final drug material. In order to better understand this process, let’s take a look at ibuprofen synthesis and the solvents that work most efficiently during this process:
The synthesis of Ibuprofen includes two extractions.
During a five-step synthesis procedure, dichloromethane is initially used to isolate the organic target material from an aqueous layer of liquid. Dichloromethane is a polar liquid that is used commonly in liquid-liquid extraction because it has high solubility.
After this, petroleum ether is used three separate times to remove different aqueous layers, leaving important organic materials in solution until eventually ibuprofen is left. Petroleum ether is frequently used in pharmacy extraction because it is a stable, non-polar liquid, whereas the organic materials (and eventually ibuprofen) are polar, so they are not affected by the solvent.
Looking for Solvents for Extraction?
Extraction Grade Solvents is committed to providing companies with the solvents needed for many diverse applications, including industrial pharmacy. To explore more about how different solvents can impact your processing and to find your perfect match, reach out to our expert team today!