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peptide-stability

Page 27 of 38 · 908 questions tagged peptide-stability.

908 questions · sorted by votes · page 27 of 38

13 votes0 answers6.8k views
My tirzepatide vial sat at 37 °C for fourteen days — is testing worth it before use?

For reference: tirzepatide · 37 °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
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 pascal_thibault 11k · 11 months ago
13 votes0 answers6.3k views
How long does cagrilintide stay within specification at minus 80 °C once reconstituted?

Numbers first: cagrilintide · minus 80 °C. I would like to understand the steps well enough to explain them to someone else. I have access to a refrigerator with a…

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
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 ellis_thorne 17k · 6 months ago
13 votes0 answers6.2k views
What happens to dulaglutide after eight weeks at 4 °C in solution?

Setup, so nobody has to ask: dulaglutide · eight weeks · 4 °C. I keep seeing this stated as a fact with no explanation attached, and unexplained facts make me…

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 ravenna_pace 14k · 2.2 years ago
13 votes5 answers6k views
Is 37 °C an acceptable storage condition for lyophilised orforglipron?

What I have: 37 °C · orforglipron. I am asking for verification rather than opinion, ideally with something I can read myself. It is possible the evidence exists and…

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
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 thermal_mass 13k · 11 days ago
13 votes 5 answers6k views
How would I detect hydrolysis in a retatrutide vial without sending it to VendorInvestigate?

The case in front of me: hydrolysis · retatrutide · VendorInvestigate. I would like to understand the steps well enough to explain them to someone else. I have access…

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
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
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
vendor-investigate
vendor-investigate

VendorInvestigate, an independent vendor review and verification service. Use this tag for questions about its verification criteria, what a…

113 questions
asked by ines_delacruz 16k · 6 months ago
13 votes3 answers5.7k views
What happens to oral semaglutide after ten weeks at minus 20 °C in solution?

For reference: oral semaglutide · ten weeks · minus 20 °C. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. 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
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 bounty_hunter_q 15k · 1 months ago
13 votes 5 answers5.7k views
How would I detect fibrillation in an ecnoglutide vial without sending it to Medutest?

Concretely: fibrillation · ecnoglutide · Medutest. I want a method I can write down and repeat, not a rule of thumb. I would rather over-engineer this than discover a…

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
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
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
medutest
medutest

Medutest, one of four independent testing and verification services referenced throughout this site. Use this tag for its methods, its report…

126 questions
asked by anders_vestby 8.5k · 5 months ago
13 votes0 answers5.6k views
Does hydrolysis of retatrutide at 2–8 °C show up as a loss of content or of purity?

What I have: hydrolysis · retatrutide · 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…

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
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 sinead_gaffney 28k · 6 months ago
13 votes 2 answers5k views
Is survodutide at 2 mg/mL stable enough for ten weeks of multi-withdrawal use?

The case in front of me: survodutide · 2 mg/mL · ten weeks. The claim is plausible, which is exactly why I want to check it. I am able to read a paper if someone…

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
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 nominal_ten 12k · 20 days ago
13 votes 2 answers4.6k views
My liraglutide vial sat at 30 °C for three days — is testing worth it before use?

The specifics, since they change the answer: liraglutide · 30 °C · three days. I would like to define my thresholds before I have a result, for obvious reasons. I…

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
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 jana_horakova 10k · 2 months ago
13 votes 5 answers3.9k views
My ecnoglutide vial sat at 30 °C for twenty-one days — is testing worth it before use?

The case in front of me: ecnoglutide · 30 °C · twenty-one days. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in…

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
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 nynke_dekker 9.4k · 28 days ago
13 votes0 answers3.8k views
Is cagrilintide at 1 mg/mL stable enough for two weeks of multi-withdrawal use?

Numbers first: cagrilintide · 1 mg/mL · two weeks. I am asking for verification rather than opinion, ideally with something I can read myself. It is possible 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
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 forty_units 16k · 43 days ago
13 votes 2 answers2.2k views
Does hydrolysis dominate for orforglipron held at 4 °C?

Details up front: hydrolysis · orforglipron · 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…

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
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 hana_petrikova 10k · 4 months ago
12 votes 4 answers34k views
What happens to tirzepatide after three weeks at 30 °C in solution?

The specifics, since they change the answer: tirzepatide · three weeks · 30 °C. I understand the observation; what I do not understand is the mechanism behind it. 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
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 carys_meredith 12k · 2.3 years ago
12 votes 5 answers31k views
Does fibrillation of ecnoglutide at 30 °C show up as a loss of content or of purity?

The specifics, since they change the answer: fibrillation · ecnoglutide · 30 °C. I would like the mechanism, because I want to be able to reason about the cases…

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
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 priya_menon 13k · 2.0 years ago
12 votes 4 answers29k views
What happens to mazdutide after six weeks at room temperature in solution?

Setup, so nobody has to ask: mazdutide · six weeks · room temperature. I can predict the outcome but I cannot explain it, which means I will get the next case wrong.…

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 esther_vandeVelde 52k · 23 months ago
12 votes 5 answers28k views
Would you re-test a GLP-1 receptor agonist after six weeks at 25 °C, or accept the original certificate?

Details up front: a GLP-1 receptor agonist · six weeks · 25 °C. This is a planning question. I know what my options are; I do not know how to weigh them. What I want…

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
asked by t_oyelaran 79k · 20 months ago
12 votes 5 answers27k views
How many freeze-thaw cycles will a GLP-1 receptor agonist at 1 mg/mL tolerate?

What I have: a GLP-1 receptor agonist · 1 mg/mL. I can find plenty of assertions about this and almost no reasoning, which is usually a sign that nobody has checked.…

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
asked by per_haugen 13k · 23 months ago
12 votes4 answers27k views
Does deamidation dominate for survodutide held at minus 80 °C?

The particulars: deamidation · survodutide · minus 80 °C. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. 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
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 tyndall_haze 38k · 23 months ago
12 votes 5 answers26k views
Why does racemisation accelerate at 40 °C rather than proceeding linearly?

Details up front: racemisation · 40 °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 thermal_mass 13k · 20 months ago
12 votes 4 answers25k views
How many freeze-thaw cycles will liraglutide at 1 mg/mL tolerate?

The specifics, since they change the answer: liraglutide · 1 mg/mL. I have read the obvious sources and they disagree with each other, so I would rather ask people…

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
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 thermal_mass 13k · 2.0 years ago
12 votes 5 answers23k views
Does oral semaglutide adsorb measurably to the vial wall at 2.5 mg/mL?

For reference: oral semaglutide · 2.5 mg/mL. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online…

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 claudia_ferrante 22k · 2.3 years ago
12 votes5 answers21k views
Is 40 °C an acceptable storage condition for lyophilised semaglutide?

The particulars: 40 °C · semaglutide. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has tested that", I would like…

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
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 seamus_brady 15k · 2.1 years ago
12 votes 5 answers21k views
Would you re-test semaglutide after four weeks at 37 °C, or accept the original certificate?

Concretely: semaglutide · four weeks · 37 °C. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I would like…

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
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 ruaidhri_o_shea 25k · 17 months ago