Filtering Peptides with a PES Filter | Step-by-Step Guide

What You'll Need

• Reconstituted peptide solution
• PES (Polyethersulfone) syringe filter (0.22μm recommended)
• Sterile syringe (3ml or 5ml)
• Sterile vial for filtered solution
• Alcohol wipes

Step-by-Step Instructions

Step 1: Prepare Your Workspace

Clean your work area thoroughly and wipe down with alcohol. Wash your hands and allow them to dry completely. Gather all necessary supplies within easy reach.

Step 2: Attach the PES Filter

Remove the PES filter from its sterile packaging. Attach the filter to your syringe by twisting clockwise until secure. Be careful not to touch the filter membrane or outlet.

Step 3: Draw Up the Peptide Solution

Remove the filter temporarily and draw up your reconstituted peptide solution into the syringe. Reattach the PES filter securely to the syringe.

Step 4: Prime the Filter

Hold the syringe upright and gently press the plunger to remove any air bubbles. Allow a small amount of solution to pass through the filter to prime it. This ensures proper filtration.

Step 5: Filter Into Sterile Vial

Insert the filter outlet into your sterile vial. Apply steady, gentle pressure to the plunger to push the solution through the filter. Do not force it - use slow, consistent pressure.

Step 6: Complete Filtration

Continue filtering until all solution has passed through. You may retain a small amount in the filter and syringe - this is normal. Cap the sterile vial immediately.

Step 7: Storage

Label your filtered peptide solution with the peptide name, concentration, and date. Store according to the peptide's specific storage requirements (typically refrigerated at 2-8°C).

Important Tips

• Always use a 0.22μm PES filter for peptide filtration
• Never reuse filters - they are single-use only
• Apply gentle, steady pressure - forcing can damage the filter
• Work quickly to minimize contamination exposure
• PES filters are ideal for peptides as they're low protein-binding