Peptide Sciences (peptidesciences.com) has permanently shut down. If you landed here looking for a review to decide whether to order — they are no longer operating. This page explains what PS was, why it was popular, and why QSC is the best verified replacement for former PS customers.
What Was Peptide Sciences?
Peptide Sciences was a US-based research compound supplier operating at peptidesciences.com. It developed a positive reputation for domestic shipping speed, compound variety, and relatively competitive pricing. The main criticism of PS from experienced researchers was the use of in-house COAs — certificates of analysis issued by Peptide Sciences themselves, rather than by an independent third-party laboratory. Without independent verification, researchers had to take purity claims on trust.
Peptide Sciences has now announced a permanent shutdown. Former customers need a new supplier.
Why QSC Is the Best Replacement
Factor
Peptide Sciences
QSC
Status
⚠ Shut down — no longer taking orders
✓ Open — shipping from US domestic warehouse now
COA Standard
In-house — self-issued by seller, not independently verifiable
Janoshik independent — publicly verifiable at verify.janoshik.com, cannot be altered post-issue
Purity
≥99% claimed (in-house)
≥99% HPLC + MS confirmed, independently verified every batch
Domestic Shipping
US domestic (closed)
US Domestic Warehouse · 2–4 business days all 50 states
Catalog Size
~60 compounds
80+ compounds — growing monthly
Novel Pipeline
Limited — no Retatrutide, Eloralintide, Orforglipron
Peptide Sciences was a US-based research compound supplier that operated for several years and developed a positive reputation within the research community for domestic shipping speed and compound availability. Their in-house COA was a limitation compared to independent third-party verification, but many researchers reported satisfactory quality. The company has now permanently shut down, and researchers need a new verified supplier.
Why did Peptide Sciences shut down?
The specific reasons for Peptide Sciences’ shutdown have not been publicly detailed. The research compound supply industry operates in a complex regulatory environment, and supplier closures occur for various reasons including regulatory pressure, operational changes, or business decisions. Regardless of reason, researchers need a reliable replacement.
What did Peptide Sciences sell?
Peptide Sciences sold research-grade peptides and compounds across multiple categories: GLP-1 class (Semaglutide, Tirzepatide), GH axis peptides (Sermorelin, Ipamorelin, CJC-1295, HGH), repair peptides (BPC-157, TB-500), neuropeptides (Semax, Selank, Oxytocin), longevity compounds (GHK-Cu, Epitalon, NAD+), sexual health (PT-141, Melanotan II), immune peptides (Thymosin Alpha-1), and ancillaries (Anastrozole, Cabergoline, Enclomiphene, Tadalafil). All these categories are now available at QSC.
Is there a Peptide Sciences discount code for QSC?
QSC doesn’t use discount codes but does offer competitive pricing across the catalog and bulk order discounts. Former Peptide Sciences customers can order directly at qscpeptide.com — no code needed. QSC pricing is competitive with former Peptide Sciences prices across all compound categories.
Former Peptide Sciences Customer? Switch to QSC
All compound categories in stock · ≥99% HPLC · Janoshik independent COA · 2–4 day US delivery
