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peptide-stability

Page 33 of 38 · 908 questions tagged peptide-stability.

908 questions · sorted by votes · page 33 of 38

7 votes5 answers12k views
My survodutide vial sat at 40 °C for five days — is testing worth it before use?

Conditions: survodutide · 40 °C · five days. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow the plan I write…

cold-chain
cold-chain

Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…

578 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
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 coring_risk 27k · 14 months ago
7 votes 5 answers11k views
Does aspartimide formation of liraglutide at room temperature show up as a loss of content or of purity?

Stated plainly: aspartimide formation · liraglutide · room temperature. This is one of those things that everyone repeats and nobody derives. This matters…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
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
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 otto_brenner 12k · 7 months ago
7 votes 5 answers8.4k views
Why does deamidation accelerate at 37 °C rather than proceeding linearly?

The specifics, since they change the answer: deamidation · 37 °C. I would like the mechanism, because I want to be able to reason about the cases nobody has written…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
asked by nominal_ten 12k · 3 months ago
7 votes5 answers6.7k views
How long does oral semaglutide stay within specification at 25 °C once reconstituted?

For reference: oral semaglutide · 25 °C. I want a method I can write down and repeat, not a rule of thumb. I would rather over-engineer this than discover a problem…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 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 pascal_thibault 11k · 9 months ago
7 votes5 answers6.4k views
How long does oral semaglutide stay within specification at 37 °C once reconstituted?

For reference: oral semaglutide · 37 °C. I have read the obvious sources and they disagree with each other, so I would rather ask people who have actually done this.…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 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 teodora_ilic 17k · 3 months ago
7 votes0 answers6.2k views
Does dimerisation dominate for cagrilintide held at minus 20 °C?

Stated plainly: dimerisation · cagrilintide · minus 20 °C. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody knows, I…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 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 k_szabo 27k · 14 months ago
7 votes2 answers5.6k views
Would you re-test ecnoglutide after twelve weeks at room temperature, or accept the original certificate?

Details up front: ecnoglutide · twelve weeks · room temperature. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will…

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
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
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 per_haugen 13k · 6 months ago
7 votes 5 answers5.4k views
Does reconstituting survodutide with sterile water for injection change anything I should know about?

Setup, so nobody has to ask: survodutide · sterile water for injection. I want to know whether this is a real physical effect or an artefact of how it is measured.…

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
bacteriostatic-water
bacteriostatic-water

Water for injection containing roughly 0.9 per cent benzyl alcohol as a bacteriostatic agent. It suppresses growth in a multiple-withdrawal vial;…

149 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
sterile-water
sterile-water

Preservative-free sterile water for injection: appropriate for a single-withdrawal presentation, a poor choice for anything you intend to open…

35 questions
asked by bea_forsberg 11k · 8 months ago
7 votes 5 answers5.1k views
Is tirzepatide at 2.5 mg/mL stable enough for twelve weeks of multi-withdrawal use?

The specifics, since they change the answer: tirzepatide · 2.5 mg/mL · twelve weeks. I would like to know whether this claim survives contact with evidence. If the…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
bacteriostatic-water
bacteriostatic-water

Water for injection containing roughly 0.9 per cent benzyl alcohol as a bacteriostatic agent. It suppresses growth in a multiple-withdrawal vial;…

149 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 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 mass_shift_18 9.7k · 11 months ago
7 votes 5 answers4.8k views
What happens to dulaglutide after two weeks at minus 20 °C in solution?

What I am working with: dulaglutide · two weeks · minus 20 °C. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 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 Dr_Tomas_Kral 53k · 7 months ago
7 votes0 answers3.9k views
Why does racemisation accelerate at 2–8 °C rather than proceeding linearly?

Details up front: racemisation · 2–8 °C. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware this may have a boring answer. I would…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
asked by assay_blank 45k · 9 months ago
7 votes 3 answers3.7k views
Does oxidation dominate for liraglutide held at 40 °C?

The case in front of me: oxidation · liraglutide · 40 °C. This is one of those things that everyone repeats and nobody derives. This matters practically, not just…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 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 shear_at_the_front 17k · 40 days ago
7 votes2 answers2.1k views
Is there any published stability data for oral semaglutide at 37 °C?

For reference: oral semaglutide · 37 °C. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has tested that", I would…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 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 stopper_core 28k · 17 days ago
7 votes 3 answers1.6k views
Why does hydrolysis accelerate at 2–8 °C rather than proceeding linearly?

Numbers first: hydrolysis · 2–8 °C. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would like to know how confident…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
asked by lyoph_cake 78k · 19 days ago
6 votes5 answers24k views
Why does hydrolysis accelerate at 4 °C rather than proceeding linearly?

Details up front: hydrolysis · 4 °C. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would like to know how confident…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
asked by lucia_marchetti 19k · 2.1 years ago
6 votes 5 answers22k views
My oral semaglutide vial sat at 40 °C for fourteen days — is testing worth it before use?

For reference: oral semaglutide · 40 °C · fourteen days. I am at the decision point and I would rather think it through than improvise. I would rather spend money on…

cold-chain
cold-chain

Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…

578 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
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 tenth_of_a_unit 57k · 19 months ago
6 votes 5 answers22k views
Is minus 80 °C an acceptable storage condition for lyophilised dulaglutide?

What I have: minus 80 °C · dulaglutide. I am asking for verification rather than opinion, ideally with something I can read myself. It is possible the evidence exists…

storage
storage

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

701 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 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 nadia_kowalczyk 20k · 2.3 years ago
6 votes 5 answers21k views
Would you re-test liraglutide after ten weeks at 30 °C, or accept the original certificate?

The particulars: liraglutide · ten weeks · 30 °C. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with explicit…

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
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
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 tobias_reint 20k · 16 months ago
6 votes 5 answers20k views
Does fibrillation of survodutide at 25 °C show up as a loss of content or of purity?

For reference: fibrillation · survodutide · 25 °C. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. I have…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
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
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 zainab_mustafa 21k · 18 months ago
6 votes5 answers16k views
How long does mazdutide stay within specification at 37 °C once reconstituted?

Numbers first: mazdutide · 37 °C. I can find plenty of assertions about this and almost no reasoning, which is usually a sign that nobody has checked. Assume no…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 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 lyoph_cake 78k · 2.0 years ago
6 votes 5 answers14k views
Is room temperature an acceptable storage condition for lyophilised survodutide?

The specifics, since they change the answer: room temperature · survodutide. Somebody stated this to me confidently and I would like to check it before repeating it.…

storage
storage

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

701 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 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 RP_C18 105k · 16 months ago
6 votes 2 answers14k views
Does oral semaglutide adsorb measurably to the vial wall at 4 mg/mL?

For reference: oral semaglutide · 4 mg/mL. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 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
storage
storage

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

701 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 jonas_ekstrom 12k · 23 months ago
6 votes 5 answers14k views
How many freeze-thaw cycles will oral semaglutide at 10 mg/mL tolerate?

The particulars: oral semaglutide · 10 mg/mL. I want a method I can write down and repeat, not a rule of thumb. I would rather over-engineer this than discover a…

freeze-thaw
freeze-thaw

What repeated freezing does to a peptide in solution: ice-crystal shear at the growing front, freeze-concentration of solutes, pH shifts as buffer…

57 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

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

701 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 wren_calloway 23k · 15 months ago
6 votes 5 answers12k views
Why did my solution foam when I added the diluent, and does it matter?

I have a logging thermometer, a box of insulin syringes and no illusions about my worktop being sterile. I have a result I cannot explain, and I would rather diagnose…

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
vial-inspection
vial-inspection

What you can learn by looking: cake morphology, meniscus films, fibres versus stopper fragments versus true particulates, clarity after…

66 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
asked by rukhsana_iqbal 17k · 18 months ago