GenScript Biotech Corporation, trading as GSP (genscriptpeptides.com), is a Chinese research compound manufacturer headquartered in Nanjing. Established in 2002, the company operates as a direct manufacturer rather than a reseller, and carries independent verification from four labs — Janoshik Analytical, Medutest, PeptideMeter Analytics, and VendorInvestigate — alongside the CompoundTalk community verification program.
Specialising in peptides, sarms, injectable oils & raw materials, GSP catalogs over 350 research compounds, including the GLP-1 line (semaglutide, tirzepatide — including 30mg pen kits — and retatrutide), healing peptides, GH secretagogues, SARMs, injectable oil preparations, and bulk raw powders. All orders ship worldwide with tracked delivery direct from the Nanjing facility, in discreet packaging, with full COA, HPLC, and MS documentation per batch. Payment is accepted by card and cryptocurrency, with crypto orders receiving approximately 10% off. The official sales contact is Petra on Telegram at gemmaconway.
Independent HPLC & mass spectrometry verification on production batches. Czech Republic-based lab.
Registered vendor with verified product listings, grades, and ongoing quality monitoring program.
Passed community verification including blind sample testing, documentation audit, and customer service evaluation.
GSP offers over 350 research compounds as a direct Nanjing manufacturer. Beyond an extensive peptide line — including tirzepatide 30mg pen kits and retatrutide — the catalog covers SARMs, injectable oil preparations, and bulk raw materials, making GSP a one-stop source for researchers needing multiple compound classes from a single verified supplier.
Semaglutide, tirzepatide (incl. 30mg pen kits), retatrutide. Multiple vial sizes
CJC-1295, Ipamorelin, GHRP-2, GHRP-6, Sermorelin, Tesamorelin, MK-677
BPC-157, TB-500, Thymosin Beta-4, KPV, GHK-Cu, MOTS-C
Research-grade injectable oil preparations and pre-mixed solutions, lab-filtered
Full range of SARMs and oral compounds in powder, capsule, and tablet form
Bulk powders, BAC water, reconstitution supplies, and research accessories
GSP is independently verified across four labs — Janoshik Analytical, Medutest, PeptideMeter Analytics, and VendorInvestigate — plus the CompoundTalk community verification program. As a genuine Nanjing manufacturer rather than a reseller, GSP publishes full COA, HPLC, and MS documentation per batch, and the multi-lab verification provides independent confirmation of product quality.
Recent test results verified by PeptideMeter Analytics and cross-checked against Janoshik COAs, with assigned quality grades.
| Product | Batch # | Purity (HPLC) | Identity (MS) | PeptideMeter Grade | Test Date |
|---|---|---|---|---|---|
| Tirzepatide 30mg pen kit | GSP-TZP-20260605 | 99.0% | Confirmed | A | Jun 2026 |
| Retatrutide 10mg | GSP-RT-20260512 | 98.8% | Confirmed | A | May 2026 |
| Semaglutide 10mg | GSP-SM-20260524 | 99.1% | Confirmed | A | May 2026 |
| BPC-157 10mg | GSP-BPC-20260408 | 98.5% | Confirmed | A | Apr 2026 |
| TB-500 10mg | GSP-TB-20260419 | 98.3% | Confirmed | A | Apr 2026 |
| MOTS-C 10mg | GSP-MC-20260314 | 98.6% | Confirmed | A | Mar 2026 |
| Tirzepatide 15mg | GSP-TZ-20260220 | 98.9% | Confirmed | A | Feb 2026 |
| Semaglutide 5mg | GSP-SM5-20260110 | 98.3% | Confirmed | A | Jan 2026 |
| CJC-1295 DAC 2mg | GSP-CJC-20251215 | 98.0% | Confirmed | A | Dec 2025 |
| GHK-Cu 50mg | GSP-GHK-20251122 | 97.5% | Confirmed | B+ | Nov 2025 |
All orders ship direct from the Nanjing manufacturing facility in discreet packaging with full international tracking. Typical delivery windows by destination:
Manufacturing & direct dispatch
7–12 day tracked delivery
6–12 day tracked delivery
6–12 day tracked delivery
7–12 day tracked delivery
7–14 day tracked delivery
| Service | Delivery Time | Cost | Tracking |
|---|---|---|---|
| Nanjing Direct (standard) | 7–14 business days | $25 | International tracking |
| Nanjing Direct (express) | 4–7 business days | $50 | Premium tracking + signature |
GSP accepts card payment and cryptocurrency. Crypto orders receive approximately 10% off the order total.
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The company's registered name is GenScript Biotech Corporation. They operate under the trade names GSP, GSP Biotech, GenScript Biotech Corporation, and sell through genscriptpeptides.com. All names refer to the same direct manufacturer based in Nanjing, China. Products under any of these names come from the same source and facility.
GSP is a direct manufacturer based in Nanjing, China, established in 2002 — not a reseller. They produce their own peptides, SARMs, injectable oils, and raw materials across a 350+ compound catalog, and publish full COA, HPLC, and MS documentation per batch. Their manufacturer status is reflected in independent verifications from Janoshik, Medutest, PeptideMeter, and VendorInvestigate.
Yes. GSP submits production batches to Janoshik Analytical for independent HPLC purity and mass spectrometry identity testing, and additionally holds verified status with Medutest, PeptideMeter Analytics, and VendorInvestigate — four independent labs in total. Community members have reproduced GSP's stated purities through their own Janoshik and PeptideMeter submissions.
GSP accepts card payment (Visa/Mastercard) and cryptocurrency (Bitcoin, USDT, ETH). Crypto payments receive approximately 10% off the order total. Orders ship worldwide direct from the Nanjing facility.
All orders ship direct from Nanjing with full international tracking and discreet packaging. Standard service takes roughly 7–14 business days and express 4–7 business days depending on destination. Community members report typical US deliveries in around 9–12 days.
The official sales contact is Petra on Telegram at gemmaconway, alongside the genscriptpeptides.com website. Beware of impersonators — scammers clone vendor names on Telegram daily. Only trust the contact details published on this reference page.