Intersection · Sourcing × third-party testing

Sourcing topics tagged third-party testing

Topics in Sourcing carrying the tag third-party testing. Testing commissioned by someone other than the seller.

43 topics

Topic	Participants	Replies	Views	Activity
How the vendor documentation pages are maintained, and by whom certificate of analysis Janoshik Analytical batch & lot numbers documentation quality Solved How the vendor documentation pages are maintained, and by whom I have a specific reason for asking rather than idle curiosity, and the context is below. Vendor documentation pages keeps being re-asked here…		2	6k	4h
Chain of custody for a sample you posted yourself PeptideMeter third-party testing Janoshik Analytical blind sampling Chain of custody for a sample you posted yourself Writing it up because I had to work it out twice and would rather nobody else did. I was wrong about chain of custody in a thread last spring and I would like…		2	7.3k	5h
Documenting a supplier's response to a discrepancy third-party testing documentation quality batch & lot numbers Solved On the subject in the title: Documenting a supplier's response to a discrepancy Working notes rather than a conclusion. A question about how a record should be read rather than about a supplier. We have…	+44	49	589	8h
Coming back to: Why our vendor pages link the storefront and mark it sponsored third-party testing batch & lot numbers certificate of analysis documentation quality Why our vendor pages link the storefront and mark it sponsored I have a specific reason for asking rather than idle curiosity, and the context is below. Reading back through what has been written here about…		2	22k	8h
Chain of custody for a sample you posted yourself — one year on VendorInvestigate Janoshik Analytical blind sampling third-party testing Posting this under the heading it deserves: Chain of custody for a sample you posted yourself — one year on Everything below is what sits behind that. Posting a small dataset on Chain of custody. It is mine,…	+28	32	50k	15h
Reporting a good result: why nobody bothers and why they should third-party testing Janoshik Analytical certificate of analysis batch & lot numbers Reporting a good result: why nobody bothers and why they should — setting out what I have, and where I think it stops being reliable. Reporting a good result: setting out the arithmetic in full, because I…		2	3.5k	17h
[2026 update] Interpreting a result that disagrees with the supplier's certificate Medutest VendorInvestigate blind sampling third-party testing Solved On the subject in the title: Interpreting a result that disagrees with the supplier's certificate Working notes rather than a conclusion. Structured report rather than an opinion, following the format the…	+121	128	51k	17h
Comparing documentation quality across the directory, tabulated third-party testing disputed Janoshik Analytical batch & lot numbers Comparing documentation quality across the directory, tabulated — setting out what I have, and where I think it stops being reliable. I have spent a fortnight trying to pin comparing documentation quality…	+7	11	29k	19h
Submitting a sample: the process end to end blind sampling PeptideMeter VendorInvestigate third-party testing On the subject in the title: Submitting a sample: the process end to end Working notes rather than a conclusion. Submitting a sample keeps being re-asked here and I think that is because the answer is…	+99	114	29k	21h
Revisiting: The report format the maintainers ask for, and why each field is there batch & lot numbers Janoshik Analytical documentation quality third-party testing Posting this under the heading it deserves: Revisiting: The report format the maintainers ask for, and why each field is there Everything below is what sits behind that. Structured report rather than an…	+100	108	57k	1d
The report format the maintainers ask for, and why each field is there disputed documentation quality batch & lot numbers certificate of analysis Solved On the subject in the title: The report format the maintainers ask for, and why each field is there Working notes rather than a conclusion. Structured report rather than an opinion, following the format the…		4	6.3k	1d
[2026 update] A report I filed that turned out to be wrong, and the correction batch & lot numbers third-party testing documentation quality certificate of analysis On the subject in the title: A report I filed that turned out to be wrong, and the correction Working notes rather than a conclusion. Structured report rather than an opinion, following the format the…	+15	19	18k	2d
How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ — does this still hold? PeptideMeter VendorInvestigate third-party testing Janoshik Analytical Asking directly, because I could not find a straight answer: How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ — does this still hold? A question about how a record should be read rather than…	+24	28	8k	1mo
Blind submission and why it changes minds — the long version Medutest third-party testing Janoshik Analytical Posting this under the heading it deserves: Blind submission and why it changes minds — the long version Everything below is what sits behind that. A narrow question about Blind submission, deliberately…	+98	113	18k	2mo
How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ — a second dataset Janoshik Analytical blind sampling PeptideMeter VendorInvestigate Solved How Janoshik, Medutest, PeptideMeter and VendorInvestigate differ — a second dataset I have a specific reason for asking rather than idle curiosity, and the context is below. Posting a small dataset on…	+42	46	46k	2mo
Second pass at: What "verified" means on our vendor pages, stated narrowly Janoshik Analytical documentation quality third-party testing batch & lot numbers Solved Second pass at: What "verified" means on our vendor pages, stated narrowly — setting out what I have, and where I think it stops being reliable. A question about how a record should be read rather than about…	+94	102	20k	3mo
[2026 update] What a purity-only report leaves out PeptideMeter third-party testing Janoshik Analytical The question in the title: What a purity-only report leaves out I will give what I have already checked below so nobody repeats it. Structured report rather than an opinion, following the format the…	+97	103	5.2k	3mo
Choosing which test to pay for, given a fixed budget third-party testing VendorInvestigate Medutest Janoshik Analytical On the subject in the title: Choosing which test to pay for, given a fixed budget Working notes rather than a conclusion. A question about how a record should be read rather than about a supplier. We have…	+60	70	49k	3mo
What a documentation review can and cannot tell you — a second dataset Janoshik Analytical VendorInvestigate blind sampling third-party testing The question in the title: What a documentation review can and cannot tell you — a second dataset I will give what I have already checked below so nobody repeats it. Posting a small dataset on documentation…		4	170	4mo
Interpreting a result that disagrees with the supplier's certificate Janoshik Analytical Medutest PeptideMeter third-party testing Interpreting a result that disagrees with the supplier's certificate Writing it up because I had to work it out twice and would rather nobody else did. Structured report rather than an opinion, following the…	+129	153	7.3k	5mo
What "verified" means on our vendor pages, stated narrowly batch & lot numbers disputed documentation quality third-party testing What "verified" means on our vendor pages, stated narrowly — that is the question, and I have not found it answered plainly anywhere I have looked. A question about how a record should be read rather than…	+27	31	27k	7mo
How the vendor documentation pages are maintained, and by whom — what changed since third-party testing disputed batch & lot numbers Solved Asking directly, because I could not find a straight answer: How the vendor documentation pages are maintained, and by whom — what changed since What changes if the standard account of vendor documentation…	+98	104	3k	8mo
What a purity-only report leaves out Medutest VendorInvestigate third-party testing PeptideMeter Solved What a purity-only report leaves out — that is the question, and I have not found it answered plainly anywhere I have looked. Purity-only: setting out the arithmetic in full, because I have had to do it twice…	+92	105	4k	8mo
Reconciling a supplier certificate with an independent result third-party testing Janoshik Analytical certificate of analysis Reconciling a supplier certificate with an independent result — setting out what I have, and where I think it stops being reliable. Reconciling a supplier certificate: setting out the arithmetic in full,…	+18	24	347	9mo
Publishing an inconvenient result: a case study Medutest VendorInvestigate third-party testing Janoshik Analytical Wiki On the subject in the title: Publishing an inconvenient result: a case study Working notes rather than a conclusion. Publishing an inconvenient result, and specifically the version of it that the…	+59	70	992	11mo
What a documentation review can and cannot tell you Medutest VendorInvestigate Janoshik Analytical blind sampling Solved Wiki What a documentation review can and cannot tell you — that is the question, and I have not found it answered plainly anywhere I have looked. Something about documentation review does not reconcile and I would…	+79	83	950	11mo
Revisiting: Filing a first vendor report: a worked example batch & lot numbers documentation quality third-party testing disputed On the subject in the title: Revisiting: Filing a first vendor report: a worked example Working notes rather than a conclusion. A question about Filing a first vendor that I think has a definite answer,…		2	60k	11mo
A report I filed that turned out to be wrong, and the correction certificate of analysis disputed third-party testing A report I filed that turned out to be wrong, and the correction Writing it up because I had to work it out twice and would rather nobody else did. Structured report rather than an opinion, following the…	+124	132	12k	13mo
Splitting a vial for two laboratories: how to do it without ruining both blind sampling PeptideMeter third-party testing Medutest Solved Splitting a vial for two laboratories: how to do it without ruining both — setting out what I have, and where I think it stops being reliable. Something about splitting a vial does not reconcile and I would…	+64	70	4.4k	13mo
The report format the maintainers ask for, and why each field is there — what changed since third-party testing disputed Janoshik Analytical The report format the maintainers ask for, and why each field is there — what changed since Writing it up because I had to work it out twice and would rather nobody else did. Structured report rather than an…	+29	35	6.6k	13mo

Sponsored Janoshik Analytical — independent third-party testingHPLC purity and mass-spectrometric identity on submitted samples, reported with the method stated. The laboratory most often cited in this community’s verification records.Independent testing → Sponsored GL Biochem (Shanghai) Ltd. — synthesis, directFounded 1998. ISO 9001 and cGMP certified, over 1,500 staff and 200-plus patents. Custom peptide synthesis and amino acid derivatives, with a batch certificate on every order.Custom synthesis →