Quick answer: Peptide Sciences officially closed in March 2026, as announced by the company. The research peptides it previously offered remain available from multiple research-use vendors, including Peptide Hackers and others, each with varying catalogs and documentation standards.
Researchers who previously sourced peptides from Peptide Sciences may seek alternatives. The compounds themselves remain available from various vendors, though product names, specifications, and documentation may differ. This guide outlines Peptide Sciences' former catalog and options for sourcing these peptides from multiple research-use suppliers.
Research Peptides: From Peptide Sciences to Modern Sourcing
Key Research Peptides Available
These peptides were staples of the Peptide Sciences catalog; many remain available from various research peptide vendors, though availability and specifications may vary.
- For tissue repair research, related products such as BPC-157 and TB-500 are in stock.
- For metabolic research in the GLP group, products like semaglutide, tirzepatide, and retatrutide are available.
- For longevity and skin research, GHK-Cu is a related product.
- For melanocortin research, PT-141 is also available for use in laboratory studies.
Researchers can browse catalogs from multiple vendors offering over fifty research peptides across major classes. Availability may differ, and some former Peptide Sciences compounds may be renamed or offered with different purity or formulation. Human use is not intended.
Consistent Documentation and Product Catalog
Many researchers valued Peptide Sciences for its documentation and catalog depth. Other vendors also provide Certificates of Analysis (COA), HPLC purity verification, and mass spectrometry data, though formats and third-party testing may vary. Researchers should independently verify COAs, including lot numbers, test dates, and analytical methods.
Enhanced Transparency and Accessibility
Peptide Sciences closed in March 2026 with an official shutdown notice, but some customers reported difficulties with refunds and order resolution. Multiple vendors now serve the research peptide market, with varying customer support and shipping options. Some vendors offer physical storefronts and same-day pickup, while others operate online only. Researchers should verify vendor legitimacy and support policies before ordering.
How to make the switch
Researchers should identify the peptide previously ordered, compare product specifications across vendors, and review available Certificates of Analysis. Local availability and shipping options vary by vendor. Confirm storage and shipping conditions to maintain peptide integrity.
For more information on the Peptide Sciences closure and vendor alternatives, see our Peptide Sciences shutdown breakdown and Stranded by Peptide Sciences? A Checklist for Choosing Your Next Vendor. These resources discuss product availability, vendor reliability, and sourcing considerations.
All products are for laboratory research only. Not for human or veterinary use.
How to Independently Verify Research Peptide Identity and Purity
For research peptides, verifying identity and purity is critical. Researchers should examine Certificates of Analysis (COA) for lot number matching, test dates, and analytical methods used, such as High-Performance Liquid Chromatography (HPLC) and mass spectrometry. HPLC quantifies purity and detects impurities, while mass spectrometry confirms molecular weight and identity. Third-party laboratory provenance and testing methods should be confirmed to ensure reliability. Independent verification helps maintain experimental integrity. [1]
Frequently Asked Questions
Did Peptide Sciences actually close, and what was the official shutdown date and announcement?
Yes, Peptide Sciences officially closed in March 2026. The company issued a shutdown notice around that time, though some customers reported limited communication regarding refunds and order resolution.
Are websites using the Peptide Sciences name affiliated with the original company?
Several websites use the Peptide Sciences name or similar branding but are unaffiliated with the original company. Researchers should verify vendor legitimacy through documentation, contact information, and third-party reviews.
What are the most reputable research-use alternatives to Peptide Sciences?
Multiple vendors now supply research peptides formerly offered by Peptide Sciences. These include Peptide Hackers and others. Researchers should compare catalogs, pricing, testing documentation, and shipping policies to select a suitable vendor.
How can a laboratory verify that a replacement peptide matches the former product’s identity and purity?
Laboratories should review Certificates of Analysis (COA) for lot numbers, test dates, and analytical methods such as HPLC and mass spectrometry. Confirming third-party laboratory provenance and matching storage or shipping conditions helps ensure the peptide matches former specifications.
What should researchers do about unresolved orders or refunds from Peptide Sciences?
Researchers with unresolved orders or refund requests should consult the official shutdown notice if available and contact any provided customer support channels. Due to the closure, some refunds may not be possible, so verifying new vendor policies is recommended.
Comparing Research Peptide Vendors Post-Peptide Sciences
After Peptide Sciences closed, several vendors emerged as alternatives for research peptides. These vendors differ in catalog breadth, pricing, documentation, and shipping options.
| Vendor | Catalog Size | COA & Testing Transparency | Shipping Options | Physical Storefronts |
|---|---|---|---|---|
| Peptide Hackers | 50+ compounds | Batch COA, HPLC, MS | Shipping, same-day pickup | Los Angeles, Newport Beach |
| Vendor B | 40+ compounds | COA available, varies | Shipping only | None |
| Vendor C | 30+ compounds | Limited COA, in-house tests | Shipping only | None |
Researchers should evaluate vendors based on their specific research needs, documentation requirements, and logistical preferences.
For a detailed checklist on choosing a new vendor, see Stranded by Peptide Sciences? A Checklist for Choosing Your Next Vendor.
Crosswalk of Former Peptide Sciences Catalog
Many peptides formerly offered by Peptide Sciences remain available but may be renamed or offered with different specifications. Below is a partial crosswalk:
| Former Peptide Sciences Product | Availability Status | Notes |
|---|---|---|
| BPC-157 | Available | Widely offered by multiple vendors |
| TB-500 | Available | Common tissue repair peptide |
| Semaglutide | Available | Offered with varying purity specs |
| Tirzepatide | Available | Some vendors provide detailed COAs |
| Retatrutide | Available | Less common, verify documentation |
| GHK-Cu | Available | Copper peptide, check vendor testing |
| PT-141 | Available | Melanocortin research peptide |
| Some proprietary blends | Unavailable or renamed | Verify exact composition and naming |
Researchers should confirm product specifications and documentation with each vendor before purchase.
Evaluating Certificates of Analysis (COA) for Research Peptides
When sourcing peptides from new vendors, researchers should independently evaluate COAs to ensure product quality:
- Lot Number Matching: Confirm the COA corresponds to the specific batch received.
- Test Dates: Recent testing dates indicate current product analysis.
- Analytical Methods: Look for HPLC and mass spectrometry data to verify purity and identity.
- Identity Confirmation: Mass spectrometry should confirm molecular weight matches the peptide.
- Third-Party Laboratory Provenance: Prefer COAs from independent labs over in-house testing for unbiased results.
For detailed guidance, see How to Verify a Research Peptide Vendor in 2026 (COA, HPLC, and Track Record).
References
Research Use Only
This article is provided for educational purposes. All peptides discussed are sold for research use only and are not intended for human consumption or therapeutic use.