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endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and what an endotoxin number on a certificate is worth.

23 questions · sorted by votes

37 votes 5 answers42k views
How many vials from a GL Biochem lot should I send for an endotoxin test?

What I am working with: GL Biochem · an endotoxin test. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

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coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by Dr_Aoife_Brennan 20k · 15 months ago
34 votes 5 answers36k views
Is an endotoxin test worth paying for on top of a purity figure for cagrilintide?

For reference: an endotoxin test · cagrilintide. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by mala_venkatesh 22k · 18 months ago
31 votes3 answers21k views
Is an endotoxin test worth paying for on top of a purity figure for mazdutide?

Conditions: an endotoxin test · mazdutide. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by kofi_mensah 18k · 23 months ago
29 votes 3 answers11k views
Bioburden, sterility and endotoxin are three different tests — what does each one actually prove?

A COA I was sent lists "Sterility: Sterile filtered (0.22 um)" and nothing else microbiological. Another lists "Bioburden: less than 10 CFU/g — Pass". A third lists…

sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
harm-reduction
harm-reduction

Reducing avoidable risk where a decision has already been made: independent verification before use, sterility practice, dose arithmetic checked…

472 questions
asked by orla_sheridan 18k · 23 months ago
27 votes5 answers61k views
Is an endotoxin test on one vial from a ten-person group buy enough for the whole split?

Setup, so nobody has to ask: an endotoxin test · a ten-person group buy. I am trying to build something sustainable rather than something thorough that I will…

group-buy
group-buy

Pooled purchasing: how the economics work, what trust structure a pool needs, splitting a single tested lot, and the failure modes when the…

41 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by hana_petrikova 10k · 2.2 years ago
27 votes 5 answers7.6k views
Is an endotoxin test worth paying for on top of a purity figure for a GLP-1 receptor agonist?

Stated plainly: an endotoxin test · a GLP-1 receptor agonist. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by area_percent 9.9k · 8 months ago
23 votes3 answers7.4k views
Where does an "EU/mg" endotoxin limit come from, and is a spec of 10 EU/mg tight or loose?

Two COAs for the same nominal product give me endotoxin specifications of "less than 10 EU/mg" and "less than 0.5 EU/mg" respectively. Both pass. The second vendor…

endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

470 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
asked by kelvin_lam 7.6k · 15 months ago
23 votes 3 answers5.3k views
Why does autoclaving not destroy endotoxin, and how many vials would you need to test to actually catch contamination?

Two things I want to understand properly rather than by rule of thumb. First: I keep reading that endotoxin survives autoclaving. Autoclaving is 121 degrees under…

endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
lyophilisation
lyophilisation

Freeze-drying: primary and secondary drying, collapse temperature, the role of bulking agents and cryoprotectants such as mannitol and trehalose,…

17 questions
research-use-only
research-use-only

What "for research use only" means as a legal and practical designation: not approved for human use, no pharmacopoeial release testing, no…

95 questions
asked by anja_hellstrom 13k · 4 months ago
22 votes 5 answers30k views
Would an endotoxin test distinguish racemisation from a synthesis impurity in survodutide?

The case in front of me: an endotoxin test · racemisation · survodutide. I suspect the honest answer is that it depends, in which case I would like to know on what.…

peptide-mapping
peptide-mapping

Enzymatic digestion followed by LC-MS/MS to confirm sequence rather than just mass. The method that catches a scrambled sequence or a D-amino-acid…

103 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
mass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by retest_please 9.7k · 15 months ago
20 votes3 answers5.9k views
How many vials from a QYB lot should I send for an endotoxin test?

What I have: QYB · an endotoxin test. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by lyoph_cake 78k · 2 months ago
19 votes 5 answers31k views
Why is endotoxin testing separate from a sterility test?

I have a logging thermometer, a box of insulin syringes and no illusions about my worktop being sterile. I can predict the outcome but I cannot explain it, which…

endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
asked by swab_and_wait 13k · 2.2 years ago
19 votes 5 answers26k views
How should I budget for an endotoxin test across a twelve-month mazdutide course?

Details up front: an endotoxin test · mazdutide. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
janoshik
janoshik

Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content…

139 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by area_percent 9.9k · 13 months ago
19 votes 3 answers17k views
Is running reconstituted peptide through a 0.22 µm syringe filter worth it, or am I just throwing away product?

I see 0.22 µm PES syringe filters recommended fairly often as a way to "sterilise" a reconstituted vial, and I see them dismissed just as often as pointless theatre.…

sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
reconstitution
reconstitution

Taking a lyophilised vial to a solution of known concentration: choice of diluent, volume selection, how to add liquid without shearing the cake,…

313 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
diluent-volume
diluent-volume

Choosing how much diluent to add, which is really a question about what you want your measurement resolution to be. Larger volumes buy you…

295 questions
asked by Dr_Yusuf_Adeyemi 54k · 18 months ago
19 votes3 answers11k views
What does "sterile" actually mean for a research vial that arrived in a padded envelope?

Vendor listings say "sterile" and "sterile filtered" more or less interchangeably, and I have started to suspect these words are doing no work at all. I would like to…

sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
research-use-only
research-use-only

What "for research use only" means as a legal and practical designation: not approved for human use, no pharmacopoeial release testing, no…

95 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
asked by tamsin_wray 9.9k · 6 months ago
15 votes0 answers5.4k views
How should I budget for an endotoxin test across a twelve-month cagrilintide course?

For reference: an endotoxin test · cagrilintide. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
janoshik
janoshik

Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content…

139 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by liam_bracken 6.9k · 6 months ago
14 votes 5 answers9.2k views
How is an endotoxin limit derived for a given dose?

For context, I am working with a 10 mg presentation and a 2 mL fill. I want the working, not the result — I need to be able to redo it with different numbers. I care…

endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
asked by wren_calloway 23k · 4 months ago
8 votes0 answers3k views
How many vials from an SSA lot should I send for an endotoxin test?

The particulars: SSA · an endotoxin test. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by pascal_thibault 11k · 2 months ago
6 votes4 answers8.6k views
How many vials from a GGPeps lot should I send for an endotoxin test?

What I am working with: GGPeps · an endotoxin test. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by cold_lane 10k · 17 months ago
6 votes5 answers6.3k views
What does an endotoxin test add for mazdutide that a purity figure does not?

Setup, so nobody has to ask: an endotoxin test · mazdutide. Both of these get recommended confidently by different people, which suggests neither is obviously right.…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by ravenna_pace 14k · 10 months ago
6 votes4 answers4k views
What does an endotoxin test add for a GLP-1 receptor agonist that a purity figure does not?

What I am working with: an endotoxin test · a GLP-1 receptor agonist. Both of these get recommended confidently by different people, which suggests neither is…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by meniscus_film 32k · 22 days ago
5 votes0 answers1.9k views
How many vials from an MKM lot should I send for an endotoxin test?

Concretely: MKM · an endotoxin test. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by two_two_micron 9.3k · 7 months ago
2 votes 5 answers14k views
What does an endotoxin test add for cagrilintide that a purity figure does not?

The particulars: an endotoxin test · cagrilintide. Both of these get recommended confidently by different people, which suggests neither is obviously right. My…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by Dr_Bram_Verhoeven 84k · 15 months ago
2 votes 5 answers5.5k views
How should I budget for an endotoxin test across a twelve-month a GLP-1 receptor agonist course?

Stated plainly: an endotoxin test · a GLP-1 receptor agonist. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questions
janoshik
janoshik

Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content…

139 questions
endotoxin
endotoxin

Bacterial endotoxin: LAL and kinetic chromogenic methods, how an endotoxin limit is derived from a dose, why endotoxin survives autoclaving, and…

23 questions
asked by swab_and_wait 13k · 19 months ago
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