Ficoll for Separation of Red Blood Cells and PBMCs

Efficient separation of PBMCs in fresh blood is essential to perform experiments in immunology for example. When I use this product, I put 12.5mL of this in a 50mL falcon and then I add the fresh blood drop by drop leaning the falcon. This step is not very easy to achieve properly so after centrifugation there can be some red blood cells remaining. When this happens, I use a specific buffer to lyse red blood cells.