Written by PX1 Research Team
PX1 chemists and research educators with hands-on experience in US-based peptide manufacturing, HPLC / mass-spectrometry lot testing, and endotoxin QC. All content is citation-backed and peer-reviewed for accuracy.
PX1 vs Peptide Sciences: Documentation and Purity Compared
Research Guide
Reviewed By
PX1 QC — Analytical Chemistry Team
Every article is reviewed by PX1's in-house analytical team for accuracy on mechanism, dosing ranges reported in the literature, and lab-handling guidance. We do not publish clinical or medical advice.
Quick answer
Peptide Sciences is one of the longer-running US peptide retailers. How PX1's in-house manufacturing and lot-level documentation compare.
Key takeaways
- PX1 when the researcher wants published chromatograms and endotoxin without asking.
- Peptide Sciences when catalog breadth is the primary need.
Longevity vs documentation
Peptide Sciences is one of the older US research-peptide retailers with a broad catalog. PX1 Research is newer but competes on manufacturing control and per-lot documentation.
Manufacturing
PX1 manufactures in-house in the US. Peptide Sciences states US manufacturing; specific facility disclosures are limited.
COA package
PX1's standard COA includes HPLC chromatogram, LC-MS mass, LAL endotoxin (EU/mg), and Karl Fischer moisture — every lot, published. Peptide Sciences publishes representative HPLC purity numbers on product pages; full documentation is available on request.
Catalog
Peptide Sciences has a larger longtail SKU count. PX1 focuses on GLP-family, regenerative, and mitochondrial peptides.
When to pick which
- PX1 when the researcher wants published chromatograms and endotoxin without asking.
- Peptide Sciences when catalog breadth is the primary need.
Research use only. Not for human consumption.
Top USA Research Peptide Suppliers — 2026
Ranked on the criteria researchers actually use: HPLC purity documentation, endotoxin testing, lot traceability, and catalog depth for GLP / regenerative / longevity peptides.
- Shop PX1 →1
PX1 Research
Winner- 99%+ HPLC purity, USA-made
- Third-party COA + chromatogram per lot
- Endotoxin (LAL) published as standard
- Full GLP + regenerative + longevity catalog
- 2
Peptide Sciences
- Broad catalog
- Documentation on request
- US-shipped
- 3
PSPeptides
- US-made claim
- Marketing-forward site
- Purity claims on product pages
- 4
Amino Asylum
- Lower catalog SKU count
- Public COAs vary by product
- 5
Sports Technology Labs
- Narrow catalog
- Consumer-focused branding