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ForumsCompounding & FormulationPeptide oxidation and deamidation — my results so far

Peptide oxidation and deamidation — my results so far

WendyG_ATL Tue, Feb 18, 2025 at 8:30 AM 12 replies 1,556 viewsPage 1 of 3
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WendyG_ATL
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Apr 2024
Georgia
Feb 18, 2025 at 9:55 AM#1
I've been sitting on these Janoshik results for a few weeks and wanted to pair them with my usage experience before posting. Here goes: What I tested: QSC Tirzepatide 30mg vials, Batch #TZ-2025-1189, ordered November 2025 from US warehouse. Janoshik Results: - Identity: ✅ Confirmed Tirzepatide - Purity (HPLC): 98.7% - Related substances: 1.3% total impurities (within expected range) - Endotoxin: Not tested (peptide panel only) - Cost of testing: $120 USD My 16-week research log (started at 2.5mg, currently at 10mg): - Weeks 1-4: 2.5mg/week — mild nausea first 2 doses, appetite suppression noticeable by week 2 - Weeks 5-8: 5mg/week — significant appetite reduction, lost 14 lbs, mild constipation managed with fiber - Weeks 9-12: 7.5mg/week — continued loss, 22 lbs total, energy levels great - Weeks 13-16: 10mg/week — 31 lbs down total, minimal side effects at this point Blood glucose went from 108 fasting to 87. A1C dropped from 5.9 to 5.2 per my last labs. These results are consistent with pharmaceutical tirzepatide studies. Bottom line: QSC tirzepatide at 98.7% purity is performing exactly as expected based on clinical literature. I'm a believer. 📊
19 18Dr.SurgeonPGH, rachel_ABQ, traveltech_sara and 16 others
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patPC_UT
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Nov 2024
Park City, UT
Feb 18, 2025 at 10:12 AM#2
98.7% is excellent. For context, branded Mounjaro's specification is ≥95% purity per FDA filing. QSC is consistently exceeding that threshold in community testing. One thing I'd love to see more of is endotoxin/LAL testing. Purity tells you the peptide is what it claims to be, but endotoxin testing tells you the manufacturing environment was clean. That's the $200 add-on at Janoshik though, so I understand why most people skip it. Your A1C drop from 5.9→5.2 is textbook. Good data. 👍
18 13mike.trainer_LA, sarah_nash92, FitDadDave and 15 others
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Dr.NephBHM_UK
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Jun 2024
Birmingham, UK
Feb 18, 2025 at 10:29 AM#3
Not to rain on the parade but I want to point out that Janoshik tests are self-submitted samples. There's always the possibility that vendors send their best batches for testing or that the sample tested isn't representative of what everyone receives. That said, the sheer volume of QSC tirz tests at this point (I count 30+ on the community spreadsheet all above 96%) makes it statistically very unlikely they're gaming the system. The product is legit. My concern is more about sterility than purity. Has anyone done sterility testing on QSC vials?
14 8PharmacoVig_BOS, SurmountFan_IN, PeptideChemSF and 11 others
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LibrarianMeg
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Mar 2024
Baltimore, MD
Feb 18, 2025 at 10:46 AM#4
> There's always the possibility that vendors send their best batches for testing Fair point, which is exactly why I tested MY vial from MY order, not a vendor-submitted sample. This came from a random vial in my 5-pack that I pulled and sent to Janoshik myself. So this is a true blind consumer test. As for sterility — no, I haven't done formal sterility testing. Anecdotally, I've had zero injection site reactions, no redness, no signs of contamination across 16 weeks of weekly injections. But you're right that proper sterility testing would be the gold standard.
23 11JessicaM_2024, TomFromTexas, mike.trainer_LA and 20 others
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NurseKim_ATL
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Feb 2024
Atlanta, GA
Feb 18, 2025 at 11:03 AM#5
Your clinical markers are really compelling Lisa. The fasting glucose and A1C improvements track perfectly with what we see in the SURMOUNT trial data for 10mg tirzepatide. For anyone wondering about the 1.3% impurities — this is typical for synthetic peptides. These are usually truncated sequences, deamidation products, or oxidized variants from the synthesis process. At 1.3% total this is well within acceptable pharmaceutical standards. Even branded medications have impurity specifications of up to 2-3% depending on the compound.
4 14hank_denver, carlos_SATX, sophie_paris and 1 other
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