I am a customer of the Finnish OP bank. Like many other people, I had more leftover money than normally during the coronavirus pandemic.
The most common protein purification technique that we use is gel filtration (also called size exclusion chromatography). In gel filtration, proteins are separated by their size (or more correctly by their "Stokes radius", which is largely determined by their size and shape). For gel filtration of large protein amounts, we bought GE Healthcare's HiLoad 26/60 Superdex 200 prep grade about 9 years ago. The performance of the column is outstanding. Being used to 30-cm-columns, we were amazed how well the column separates between e.g. dimeric and monomeric forms of our pet protein. However, the column lost dramatically its performance recently...