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ISOLUTE^® PPT+                                                           
Protein Precipitation Plates

Benefits 'Solvent first' methodology Eliminate cloudy extracts No well blockage No vortex mixing required Optimized for automation

ISOLUTE PPT+ Protein Precipitation Plates improve removal of unwanted proteins from biological fluid samples using a 'solvent first' methodology. Designed to eliminate the need for time consuming vortex mixing or plate inversion, results show the ISOLUTE PPT+ plate removes 90% of residual endogenous material, compared with 60-65% using 'plasma first' methods.

'Solvent First' Procedure Maximizes Precipitation Efficiency
The proprietary functionalized bottom frit holds up organic precipitation solvent while the plasma sample is added, maximizing contact time and giving the most efficient precipitation effect. No vortex mixing is required. The filtrate does not pass into the collection plate until vacuum is applied.

Depth Filter Eliminates Well Blocking
Unlike membrane based devices, the system has an optimized porosity distribution and acts as a depth filter, holding up the precipitated protein without well blockage.

Rapid Non-Selective Sample Clean-up
Using the 'solvent first' methodology, ISOLUTE PPT+ plates consistently produce clear filtrates. This reduces ion suppression and improves the accuracy of LC-MS/MS analysis compared to alternative protein precipitation procedures. Up to 96 samples containing acidic, basic or neutral drug compounds can be purified simultaneously in less than ten minutes.

Technical Details
'Solvent First' Methodology using ISOLUTE PPT+ Protein Precipitation Plates

• ISOLUTE PPT+ plates can be used to process plasma sample volumes from 15 to 400 µL. Serum or blood samples can also be processed.
• The recommended crash solvent is acetonitrile, at a solvent: plasma ratio of 3:1 (v/v). Acetonitrile has been found to be a more effective solvent for precipitating protein than methanol; it produces filtrates with a lower protein concentration.
• Alternatively, acid precipitation may be used e.g., 1 M trichloroacetic acid (TCA) in a 3:1 (v/v) ratio (TCA / plasma). The same dispensing method should be used for these alternative precipitating solvents, and no dripping will occur until vacuum is applied.

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