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water-content

Page 2 of 3 · 51 questions tagged water-content.

51 questions · sorted by votes · page 2 of 3

21 votes5 answers8.4k views
How much of the gross mass of a 40 mg tirzepatide vial is actually peptide?

The case in front of me: 40 mg · tirzepatide. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 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 fibre_or_fragment 13k · 2 months ago
21 votes5 answers5.1k views
Does a desiccant sachet in the box do anything useful?

This is a recurring problem with one particular shipping lane rather than a one-off. I want to know whether this is a real physical effect or an artefact of how it is…

storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 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
asked by leah_ferrers 12k · 5 months ago
20 votes 5 answers22k views
How much of the gross mass of a 20 mg mazdutide vial is actually peptide?

Stated plainly: 20 mg · mazdutide. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude and it seems…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 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 olu_babatunde 6.2k · 20 months ago
20 votes 5 answers11k views
How much of the gross mass of a 60 mg cagrilintide vial is actually peptide?

Setup, so nobody has to ask: 60 mg · cagrilintide. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 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 seamus_brady 15k · 7 months ago
20 votes 1 answer4.6k views
How many vials from a WWB lot should I send for a Karl Fischer water content test?

What I am working with: WWB · a Karl Fischer water content test. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
asked by noor_alhassan 11k · 6 months ago
19 votes0 answers12k views
Is a Karl Fischer water content test worth paying for on top of a purity figure for liraglutide?

The case in front of me: a Karl Fischer water content test · liraglutide. I want to decide this in advance so that I am not deciding it under pressure later. Assume I…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by anouk_desmet 16k · 13 months ago
18 votes 5 answers24k views
How much of the gross mass of a 2.5 mg tirzepatide vial is actually peptide?

Conditions: 2.5 mg · tirzepatide. Please show the division. I want to check my own against yours. I would like the general form as well as the specific number, so I…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 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 fresh_bac 9.7k · 2.1 years ago
18 votes2 answers11k views
How much of the gross mass of a 2.5 mg oral semaglutide vial is actually peptide?

Concretely: 2.5 mg · oral semaglutide. Please show the division. I want to check my own against yours. I would like the general form as well as the specific number,…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
oral-glp1
oral-glp1

Oral routes for GLP-1 receptor agonism: peptide formulations rescued by absorption enhancers such as SNAC, and true small molecules that need no…

219 questions
asked by tri_gly_ala 24k · 9 months ago
16 votes4 answers12k views
How much of the gross vial mass is peptide, water and counter-ion?

I have the report as a PDF with the chromatogram on page two, so I can quote specifics. This should be a straightforward calculation and I keep getting two different…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
asked by sample_id 17k · 7 months ago
14 votes 5 answers16k views
How much of the gross mass of a 15 mg semaglutide vial is actually peptide?

The particulars: 15 mg · semaglutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 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
asked by sample_id 17k · 2.1 years ago
14 votes5 answers15k views
How much of the gross mass of a 30 mg dulaglutide vial is actually peptide?

Details up front: 30 mg · dulaglutide. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
dulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

200 questions
asked by rune_thoresen 16k · 12 months ago
14 votes3 answers3.9k views
How much of the gross mass of a 15 mg ecnoglutide vial is actually peptide?

The specifics, since they change the answer: 15 mg · ecnoglutide. I would rather understand the derivation than memorise the outcome. Two people I asked gave two…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
asked by e_dziedzic 51k · 1 months ago
13 votes 1 answer3.6k views
How much of the gross mass of a 50 mg survodutide vial is actually peptide?

The particulars: 50 mg · survodutide. I would rather understand the derivation than memorise the outcome. Two people I asked gave two answers that differ by a factor…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 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 dermot_kiely 12k · 1 months ago
12 votes 5 answers14k views
How much of the gross mass of a 30 mg retatrutide vial is actually peptide?

Details up front: 30 mg · retatrutide. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method 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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
retatrutide
retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

251 questions
asked by pierce_count 24k · 8 months ago
12 votes 4 answers13k views
How much of the gross mass of a 2 mg dulaglutide vial is actually peptide?

What I have: 2 mg · dulaglutide. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method is what…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
dulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

200 questions
asked by ahmed_zerouali 15k · 7 months ago
12 votes0 answers3.2k views
How much of the gross mass of a 30 mg orforglipron vial is actually peptide?

What I have: 30 mg · orforglipron. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would rather…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
orforglipron
orforglipron

A non-peptide, orally bioavailable small-molecule GLP-1 receptor agonist studied in the ATTAIN programme. It is not a peptide, which changes…

219 questions
asked by p_mkhize 58k · 3 months ago
8 votes5 answers11k views
Is loss on drying interchangeable with Karl Fischer?

I have both a purity figure and a content figure, which is why the discrepancy is visible. I am trying to choose between two options that are usually discussed as…

water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 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
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
asked by tandem_gradient 61k · 12 months ago
8 votes5 answers9.5k views
What does a Karl Fischer water content test add for tirzepatide that a purity figure does not?

Setup, so nobody has to ask: a Karl Fischer water content test · tirzepatide. These are treated as interchangeable and I do not think they are. If both are acceptable…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 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 Dr_Ilse_Vandenberg 113k · 8 months ago
7 votes0 answers1.6k views
What does a Karl Fischer water content test add for oral semaglutide that a purity figure does not?

Conditions: a Karl Fischer water content test · oral semaglutide. These are treated as interchangeable and I do not think they are. If both are acceptable I would…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
oral-glp1
oral-glp1

Oral routes for GLP-1 receptor agonism: peptide formulations rescued by absorption enhancers such as SNAC, and true small molecules that need no…

219 questions
asked by cold_lane 10k · 2 months ago
6 votes 1 answer2.9k views
How many vials from a KP lot should I send for a Karl Fischer water content test?

For reference: KP · a Karl Fischer water content test. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
asked by ines_delacruz 16k · 4 months ago
5 votes5 answers27k views
How much of the gross mass of a 60 mg a GLP-1 receptor agonist vial is actually peptide?

Setup, so nobody has to ask: 60 mg · a GLP-1 receptor agonist. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
asked by jana_horakova 10k · 2.0 years ago
5 votes 5 answers8.6k views
How much of the gross mass of a 5 mg mazdutide vial is actually peptide?

What I am working with: 5 mg · mazdutide. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude and…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 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 per_haugen 13k · 2.2 years ago
4 votes 5 answers4.6k views
How much of the gross mass of a 2.5 mg liraglutide vial is actually peptide?

Concretely: 2.5 mg · liraglutide. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as well as the…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

88 questions
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by pieter_maas 14k · 11 months ago
4 votes 5 answers3.9k views
How many vials from an SGN lot should I send for a Karl Fischer water content test?

Stated plainly: SGN · a Karl Fischer water content test. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

51 questions
asked by jonas_ekstrom 12k · 5 months ago