paradigm peptides FAQ

Verify peptide purity and sequence first, then check storage and reconstitution protocols. Discrepancies between your results and published studies using the same peptide are almost always traceable to one of three variables: peptide degradation (oxidation, aggregation, or hydrolysis during storage), incorrect reconstitution solvent (using water instead of DMSO for hydrophobic peptides, or vice versa), or receptor expression variability in your cell line versus the literature model. Contact your peptide supplier. If you're using a paradigm peptides alternative like Real Peptides, direct researcher support can help identify whether the issue is peptide-related or experimental design-related before you waste additional time troubleshooting in the wrong direction.

Switch suppliers immediately and document the batch number. A purity drop below specification indicates synthesis protocol failure, contamination during lyophilization, or improper storage before shipment. Do not attempt to 'salvage' the peptide by adjusting your experimental dose. Deletion sequences and oxidation products cannot be compensated for by increasing concentration. Contact your current supplier for a refund or replacement, then source from a paradigm peptides alternative with batch-specific COA documentation like Real Peptides to ensure the replacement batch is verified before you invest additional research time.

Request custom synthesis. Real Peptides offers custom peptide synthesis for sequences not available in the standard catalog, provided the sequence is within synthesis capability (typically ≤50 amino acids for solid-phase synthesis). Custom synthesis timelines range from 4–8 weeks depending on sequence complexity, required purity grade, and scale. This is standard across the industry. No peptide supplier stocks every possible sequence. The advantage of using a small-batch synthesis facility for custom work is that your peptide receives the same quality control protocols as catalog products: sequence verification, third-party purity testing, and batch-specific documentation.

Real Peptides offers custom synthesis for novel sequences or modified peptides not available as stock items. The process includes consultation on solubility prediction, synthesis feasibility assessment, and timeline estimation based on sequence length and complexity. Custom synthesis follows the same cGMP protocols and third-party testing as catalogue products—HPLC, ESI-MS, and endotoxin testing are standard. Paradigm Peptides does not advertise custom synthesis services, focusing instead on expanding the existing catalogue based on market demand.

This indicates protein aggregation from improper lyophilisation or thermal degradation during storage or shipping. Do not use the solution—aggregated peptides have altered receptor binding profiles and may be immunogenic in animal models. Contact the supplier for a replacement, and request ESI-MS data confirming the peptide's molecular weight matches the expected value. If cloudiness persists across multiple batches from the same supplier, the issue is process control, not isolated batch failure. Real Peptides uses pharmaceutical-grade lyophilisation with terminal moisture content below 1.5%, which prevents aggregation during reconstitution.

Switch to a supplier with published endotoxin testing below 1.0 EU/mg and repeat the assay with fresh peptide. Lipopolysaccharide contamination triggers inflammatory responses in mammalian cells at concentrations invisible to standard purity testing—it won't show up on HPLC chromatograms. If the cytokine expression normalises with endotoxin-tested peptide, the original batch was contaminated. Real Peptides includes LAL assay data with every order; if your current supplier doesn't, you're flying blind on the single most common cause of irreproducible cell culture results.