Exosome precipitation solutions alone leave a large amount of non-exosomal proteins in samples. Exo-spin™ kits are suitable for the preparation of pure exosomes from a variety of biological fluids including blood plasma/sera, cell culture media, urine, saliva. Kits are available for 24 and 48 samples and in mini-spin column and midi drip-column sizes. Exo-spin™ kits offer excellent quality and value-for-money.
Choosing Exo-spin™ products
The final step of Exo-spin™ uses Size Exclusion Chromatography (SEC) and has been calibrated to purify particles in the range of 30 – 400 nm; the same size range achieved with ultracentrifugation. This range covers all commonly accepted definitions of exosome size. Exo-spin™ technology is superior to techniques that rely solely on precipitation which result in co-purification of large amounts of non-exosomal proteins and other material as well as carry over of the precipitant.
Exo-spin™ provides various configurations and options for use. The basic protocol requires precipitation followed by further purification by SEC columns. In cases where exosome concentrations are high, the precipitation step may be omitted. Indeed, eliminating the precipitation step is essential for applications such as mass spectrometry, which will not work in the presence of any precipitant. For blood samples, exosome concentrations are typically on the order of 1x1012 particles per ml and precipitation is therefore not usually required. Direct column purification of exosomes from blood sera, without the need for any precipitation, can rapidly be achieved using product EX03 (for samples up to 0.1 ml) and product EX04 (for samples up to 1 ml).
Cell culture typically generates yields of 1x109 particles per ml or less. Use of cell culture devices such as the Integra CELLine flask can increase the concentration of exosomes in the media by around 10-fold, obviating the need for precipitation. When processing of larger sample volumes is required, precipitation buffer concentrates exosomes prior to column purification. Use EX01 for cell culture, urine, saliva etc. and EX02 for blood.
A tabular guide to choosing Exo-spin™ products is here.
Whatever the sample and whatever the application, there is an Exo-spin™ product for your needs. If you need any help selecting your product, please contact us and we’ll get straight back to you.