Montage Albumin Deplete Kit From Millipore

Millipore’s Montage Albumin Deplete Kit contains affinity columns which specifically bind albumin without much non-specific binding to the other proteins present in serum/plasma. Removal of albumin allows for detection of low abundance proteins using techniques like gel electrophoresis. It is better than the traditional Cibacron Blue resin-based depletion of albumin.

Millipore’s Montage Albumin Deplete Kit (LSKA D00 24) comes in a pack for processing 24 samples together. It contains 30 ml equilibration buffer, 12 ml wash buffer, 12 ml strip buffer, micro centrifuge tubes and affinity columns which are sufficient to deplete albumin from 24 serum/plasma samples. The kit is to be stored at 2-8ºC. Albumin depletion with this kit is very quick and does not require other reagents. The column contains affinity resin and should be equilibrated with equilibration buffer before use. For this, 400 ul of equilibration buffer is added to the affinity column and centrifuged at 2000 rpm for 2 min, the flow through is discarded and this step is repeated once. Serum/plasma should be diluted before its application onto affinity column. 10 ul of serum/plasma is diluted in 190 ul of equilibration buffer and then placed on the column; the column is then spun at 2000 rpm for 2 min and the flow through is recovered. This flow through is added back to the same column and centrifuged at 2000 rpm for 2 min and the flow through is again collected. In order to reduce non-specific binding, 200 ul of wash buffer is added in the column and the column is centrifuged at 2000 rpm for 2 min and the flow through is collected. This step is repeated once and the collected 400 ul of flow through is added to the previous collections of flow through. Optionally, elution of the bound, albumin-containing fraction can also be done by adding 400 ul of stripping buffer to the column and centrifuging at 2000 rpm for 2 min and collecting the eluate. The flow through and eluted fractions can be run on one-dimensional SDS-PAGE for analysis. For 2 dimensional gel electrophoresis (2DE), we ethanol precipitate and resuspend the albumin-depleted serum sample in buffer containing 8 M urea, 2 M thiourea, 1% DTT and 2% CHAPS.

We are working on serum proteomics. Our research involves separation of serum proteins collected from cancer patients and healthy individuals, on 2D gels followed by visualization by silver staining. The presence of albumin hinders detection of low abundant proteins present in the serum and masks proteins which have the same molecular weight and pI as albumin. This problem was solved with Millipore’s Montage Albumin Deplete Kit. Depleting albumin from serum before doing 2D separation results in better resolution and detection of low abundant proteins. I got better separation of serum proteins after using this kit, without significant loss of other proteins.

I, therefore, recommend Millipore’s Montage Albumin Deplete Kit for quick and reproducible depletion of albumin in order to get better resolution of low abundant proteins.