The first stage of making a medicine is to manufacture the active ingredient. We call this stage the primary manufacture. The active ingredient will normally make up a small proportion of the final medicine. However, it is the part that will actually make the patient well again.
There are two main ways of developing the active ingredient:
You can find out about biotechnology on the next page.
Chemical technology
Primary manufacture often involves chemical reactions to create new molecules. There can be many stages to these reactions. The diagram below shows a simple example in which two ingredients are reacted together. One of the products of this reaction is the active ingredient. However, there are other products as well. The chemists need to isolate and purify the active ingredient using a variety of techniques.
In our example, the active ingredient is in a solution so the mixture can be filtered to remove any unwanted residues. The active ingredient will then crystallise when the solvent is allowed to evaporate. Sometimes there will need to be more stages before a completely pure sample is produced.
Over the last two decades, there has been an increasing use of biological techniques rather than chemical ones. We call this biotechnology.
