Focusing on Your Proteins

The Biomotif pI-TRAP™ System delivers a reproducible strategy to dig deeper into your samples for enhanced biomarker discovery. Setting the new benchmark for gel-free MS-compatible, pI-fractionation of peptides and proteins. The pI-TRAP System integrates sample loading, on-line desalting, isoelectric focusing (IEF) and fraction collection in a routine instrument. Proprietary Biomotif pI-CELL™ technology enables re-focusing after every fraction collection step to preserve the resolution of IEF …fraction after fraction after fraction. Conventional IEF systems have protein capacities in the nanogram or milligram range. pI-TRAP works in the 100 microgram range of protein …precisely optimized for LC-MS-MS.

Gel-Free Fractionation

The Biomotif multi-junction capillary isoelectric focusing (MJ-CIEF) pI-Cell overcomes the limitations of conventional IEF. The pI-CELL contains a sequence of buffer wells connected by a semipermeable IEF capillary. The wells maintain the pH gradient, and the wells can be programed to provide the optimum voltage gradient ….step by step by step.

After isoelectric focusing a carrier buffer mobilizes the focused proteins towards the fraction collector. This process can causes band broadening of any residual proteins in the IEF capillary. The Biomotif pI-CELL uniquely enables recursive re-focusing, after every fraction collection step, to counteract band broadening effects in the capillary. This unique technology allows up to 30 (re-focused) fractions to be collected automatically, while preserving the advantages of the primary isoelectric separation …and all in about one hour.

The pI-TRAP System is a highly versatile preparative device that can leverage almost every proteomics workflow.

The New Domain in Biomarker Discovery the pI-TRAP can rapidly fractionate plasma or serum without immunodepletion. Desired pI regions can be precisely targeted to yield fractions rich in biomarkers, and reveal the protein pI shift discovery domain.

Deep Proteome Coverage is facilitated by reproducible fractionation of complex digest mixtures before reversed-phase LC-MS-MS. The pI-TRAP provides an orthogonal separation to Strong Cationic or Anionic Exchange. With the pI-TRAP you obtain up to 30 fractions in one hour without using aggressive buffers or salts, and the fractions produced exhibit minimal overlap.

Rapid Sample Clean-Up with overall losses of less than 10 %. Protein or peptide mixtures can be injected into the pI-TRAP System for on-line desalting in a 10 minute wash cycle prior to IEF. With the pI-TRAP System you can reproducibly clean-up even tiny amounts of sample in minutes.

Enabling Analytical Metric with the power of pI. The theoretical pI of a peptide or protein can be calculated much more accurate than hydrophobicity. The accuracy of pI determination with the pI-Trap (±0.2 pI-units) is significantly better than with conventional wide range gels. The pI-TRAP System makes pI an enabling metric.

100 Microgram Protein Capacity of the pI-TRAP makes it the perfectly matched partner for state-of-the-art LC-MS-MS based proteomics research.


Application Notes


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