Understand the source comparison
Real Peptides Follistatin-344 vs Competitors: Quality Comparison
Synthesis Method Small-batch SPPS with automated coupling Large-scale SPPS or liquid-phase Liquid-phase bulk synthesis Small-batch SPPS minimizes sequence errors and cumulative coupling failures. Critical for long peptides like Follistatin-344 (315 amino acids
No winner is assigned.
This page preserves a source comparison for education. It does not add a rating, recommendation or clinical judgment.
- Synthesis Method
- Small-batch SPPS with automated coupling
- Large-scale SPPS or liquid-phase
- Liquid-phase bulk synthesis
- Small-batch SPPS minimizes sequence errors and cumulative coupling failures. Critical for long peptides like Follistatin-344 (315 amino acids)
- Purity Verification
- Batch-specific HPLC, every production run
- Representative sampling from bulk batches
- CoA provided on request, often generic
- Batch-specific testing catches run-to-run synthesis variance that representative sampling misses. Non-negotiable for reproducible studies
- Molecular Weight Confirmation
- MALDI-TOF mass spec per batch
- Mass spec on select samples
- Rarely confirmed independently
- Mass spectrometry is the only method that confirms exact sequence integrity. HPLC alone can't distinguish truncated sequences from full-length product
- Documented Purity
- ≥98% verified by HPLC
- 85–95% claimed, variance not disclosed
- 70–85% typical, verification inconsistent
- Purity below 95% introduces uncontrolled variables in dose-response studies. Acceptable for preliminary work, unacceptable for publication-grade research
- Endotoxin Testing
- LAL assay, <1 EU/mg certified
- Sometimes tested, threshold varies
- Not routinely tested
- Endotoxin contamination above 1 EU/mg triggers immune responses in cell culture. Confounds inflammation and cytokine studies entirely
- Price Per Milligram
- $180–$240 per 5mg vial
- $90–$150 per 5mg vial
- $40–$80 per 5mg vial
- The cost difference reflects quality infrastructure. Synthesis precision, analytical verification, and cold-chain logistics. Not brand markup