So we have many, many examples of these specific proteins, these proteins that bind to specific molecules and have high affinity for these molecules. So this is another property that we can use to separate proteins. And the method that uses this property is known as affinity chromatography. So a method called affinity chromatography basically separates, allows us to purify and isolate specific type of protein molecules from within a mixture of proteins based on their affinity to bind to specific molecules. Now, just like in gel filtration chromatography, an ion exchange chromatography, we also have the same exact setup in affinity chromatography. So we have a funnel.