Solid Phase Extraction
PolyLC offers all of its materials in cartridges for SPE as well as additional materials:
NuTips®: Available for samples 1-10 µl and 10-200 µl. The stationary phase is embedded in the wall with an open channel in the center. Sample is pipetted up and down to promote solute capture. These are convenient for desalting or quick sampling and spotting on a MALDI target. However, if the amount of peptide being sampled greatly exceeds the capacity of the NuTip (or any other SPE cartridge, for that matter), then the peptides that bind with highest affinity will be present in sufficient quantity to displace the others. Result: A nonrepresentative sampling of the mixture.
TopTips®: Available for samples 1-10, 10-200, and 200-1000 µl.
Their capacity is much greater than that of NuTips or other microscale SPE cartridges. This permits the entire sample to be bound and cleaned up, a safe way to avoid selective loss of components. The following figure shows the removal of 1-2 M urea from a tryptic digest with a HILIC TopTip.
HILIC NuTips and TopTips can also remove detergents from protein and peptide samples.
SPE cartridges: These are for samples up to 5 ml or larger in size. Available in closed cartridges with luer fittings or in packed syringe barrels. Click here to order.
NuTip® and TopTip® are trademarks of Glygen Corp.