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ForumsCOA & Analytical TestingEndotoxin testing methods — what worked for you?

Endotoxin testing methods — what worked for you?

kevin_tulsa Wed, Jul 24, 2024 at 2:46 AM 37 replies 2,040 viewsPage 1 of 8
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kevin_tulsa
Member
489
2,123
Jun 2024
Tulsa, OK
Jul 24, 2024 at 4:11 AM#1
After a lot of discussion across multiple threads, I'm formally launching the CompoundTalk Community Testing Initiative. The idea is simple: pool our money to get rigorous third-party testing on popular peptide vendors, then share the results publicly. Why? - Individual testing costs $120-$150 per sample (Janoshik full panel) - Most people can't or won't spend that on top of the product cost - Vendor-provided COAs have an inherent conflict of interest - Community-funded testing is independent, unbiased, and benefits everyone How it works: Phase 1 — Vendor Selection (this week) Members vote on which vendors/batches to test first. Priority goes to: - High-volume vendors (most people affected by results) - Vendors with no existing third-party data - Vendors with conflicting reports or quality concerns Phase 2 — Sample Acquisition (next week) A designated purchaser buys one vial from the selected vendor using a fresh account (so the vendor doesn't know it's a test order). This prevents vendors from "cherry-picking" higher-quality product for known testers. Phase 3 — Testing Sample is sent to Janoshik for the full panel: - HPLC purity (220nm, gradient method) - Content/potency vs. reference standard - ESI-MS identity confirmation - Sterility (USP <71>) — added if budget allows - Endotoxin (LAL) — added if budget allows Phase 4 — Results Publication Full COA posted on the forum with analysis and interpretation. Results are permanent public record. Cost structure: - Basic panel (HPLC + content + MS): $130 - With sterility: +$80 ($210 total) - With sterility + endotoxin: +$50 ($260 total) - Product cost (vial + shipping): $80-$200 depending on vendor - Shipping to lab: $25-$40 Total per test: $235-$500 depending on scope. With 15-25 participants contributing $15-$25 each, this is very doable. I've set up a dedicated fund (details via DM to verified members with 50+ posts and 6+ month account age). First round targets (vote below): 1. ResearchChem Outlet — new grey-cap batch (untested) 2. GLP1Direct — only 2 existing COAs, needs more data 3. PeptideSciencesRx — last COA is from October 2025 4. CompoundPharm Direct — current batch verification 5. A "wildcard" vendor nominated by the community Reply with your votes (pick 2) and whether you want to contribute. Let's build the most trusted testing database in the peptide community.
35 0fiona_glasgow, Dr.RheumBOS, greg_boulder and 32 others
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SleepDoc_PDX
Member
289
1,234
Sep 2024
Portland, OR
Jul 24, 2024 at 4:28 AM#2
Love this initiative. I'm in for $25/round. My votes: #1 (ResearchChem Outlet) and #3 (PeptideSciencesRx). ResearchChem because the batch change is concerning and a lot of budget-conscious members here rely on them. If the new batches are good, it helps a lot of people. If they're not, it prevents a lot of people from wasting money (or worse). PeptideSciencesRx because their October COA is getting stale. Five months without fresh data for a vendor that many people here use regularly isn't acceptable. One suggestion for process improvement: when the designated purchaser buys the sample, have them photograph the unboxing — vial label, lot number, packaging condition. This creates a chain-of-custody record from purchase through testing. If a vendor later disputes the results, we have documentation showing the product was purchased normally and tested as-received.
Last edited: Jul 24, 2024 at 7:28 AM
8 3hank_denver, carlos_SATX, sophie_paris and 5 others
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adam_van
Member
212
890
Nov 2024
Vancouver, CA
Jul 24, 2024 at 4:45 AM#3
Great initiative. Votes: #1 and #2. I'll contribute $20/round. Process question: how do we prevent the coordinator from tampering with samples? I'm not accusing anyone — but for the results to be truly trustworthy, the chain of custody needs to be airtight. Ideas: 1. Blind purchasing: The purchaser and the lab submitter are different people. Purchaser sends sealed vial directly to the submitter. 2. Duplicate testing: For high-stakes tests (e.g., vendor with quality concerns), send two samples from the same vial to two different labs. 3. Tamper-evident packaging: Purchaser photographs the intact seal before shipping to the submitter. Yes, this adds complexity and cost. But if the initiative's results are going to carry weight in the community, the methodology needs to be beyond reproach.
48 24LindaRN_retired, tommy_boulder, hyun_seoul and 45 others
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PeptideMeter — Independent Peptide Analytics

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mel_PDX
Member
189
890
Dec 2024
Portland, OR
Jul 24, 2024 at 5:02 AM#4
Both excellent points. Here's the updated protocol addressing chain of custody: Chain of Custody Protocol v1.1: 1. Designated purchaser (randomly selected from volunteer pool) orders the product using their own account. They record: order date, order confirmation screenshot, vendor, batch/lot number if visible at purchase. 2. Upon arrival: Purchaser photographs the sealed package, the vial (label, cap, lot number), and any included documentation. Photos are timestamped and uploaded to a shared album visible to all contributors. 3. Shipping to lab: Purchaser ships the unopened vial directly to Janoshik. They photograph the shipping label and provide the tracking number to the coordinator. The vial is shipped with appropriate cold chain (insulated mailer + ice pack) if required. 4. Lab receives and tests. Janoshik's COA includes the date received, sample description on arrival, and unique sample ID. This matches against the purchaser's documentation. 5. Results published on the forum with all supporting documentation (purchase confirmation, unboxing photos, shipping receipt, COA). For high-stakes tests: We can implement QualityQueen's duplicate testing suggestion. Two vials purchased from the same batch by two different people, sent to two different labs. If both results agree, it's very strong data. Budget doubles, but it's worth it for vendors with quality concerns. Cost for dual-lab testing: ~$500-$700 per vendor. With 25 contributors at $25 each, that's $625 — just enough. Revised ask: who's willing to contribute $25/round for a robust, dual-lab testing protocol? DM me if interested.
Last edited: Jul 24, 2024 at 11:02 AM
29 22BiostatsBrad, PeptideSynthNJ, Dr.KarenChen and 26 others
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LarryQC_SD
Senior Member
2,123
9,876
Jan 2024
San Diego, CA
Jul 24, 2024 at 5:19 AM#5
I want to share some data from our previous informal testing efforts to show why this initiative matters: Cumulative community testing results (2024-2025, from forum archives): - Total samples tested: 47 - Passed all specifications: 38 (80.9%) - Failed purity (<95%): 4 (8.5%) - Failed content (<90% label claim): 3 (6.4%) - Failed identity (wrong compound): 1 (2.1%) - Contamination/sterility fail: 1 (2.1%) The failure that stands out: One sample labeled as semaglutide in August 2024 turned out to be a completely different peptide on mass spec — the observed molecular weight was 2933 Da, consistent with a GH secretagogue (likely modified GHRP-6). That vendor was immediately blacklisted and the information potentially prevented dozens of people from injecting a product that was completely mislabeled. That single test justified the entire community testing concept. One COA cost $130 and potentially saved 50+ people from injecting an unknown substance. At scale, the value proposition only gets stronger. The 80.9% pass rate tells us that most products are what they claim, but 1 in 5 has some quality issue. That's too high a failure rate to skip testing.
37 13dan_philly, MeganSA_TX, LarryQC_SD and 34 others
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