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peptide-stability

Page 24 of 35 · 832 questions tagged peptide-stability.

832 questions · sorted by votes · page 24 of 35

13 votes 5 answers19k views
How long does survodutide stay within specification at room temperature once reconstituted?

Concretely: survodutide · room temperature. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have already made one mistake…

peptide-stability
peptide-stability

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

832 questions
storage
storage

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

646 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…

301 questions
asked by lukas_sedlacek 17k · 2.2 years ago
13 votes0 answers17k views
Does retatrutide adsorb measurably to the vial wall at 2 mg/mL?

What I am working with: retatrutide · 2 mg/mL. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked the order of magnitude…

peptide-stability
peptide-stability

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

832 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…

438 questions
storage
storage

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

646 questions
asked by Dr_Ingrid_Baumgartner 39k · 2.2 years ago
13 votes 5 answers17k views
Does racemisation of dulaglutide at minus 80 °C show up as a loss of content or of purity?

Details up front: racemisation · dulaglutide · minus 80 °C. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would…

peptide-stability
peptide-stability

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

832 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…

438 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…

788 questions
asked by void_volume 13k · 17 months ago
13 votes5 answers13k views
Does survodutide adsorb measurably to the vial wall at 2 mg/mL?

Concretely: survodutide · 2 mg/mL. 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…

peptide-stability
peptide-stability

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

832 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…

438 questions
storage
storage

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

646 questions
asked by anouk_desmet 18k · 8 months ago
13 votes5 answers13k views
Would you re-test ecnoglutide after four weeks at 40 °C, or accept the original certificate?

The case in front of me: ecnoglutide · four weeks · 40 °C. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and…

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…

865 questions
peptide-stability
peptide-stability

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

832 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…

749 questions
asked by Dr_Aoife_Brennan 50k · 6 months ago
13 votes 5 answers12k views
Does dimerisation dominate for cagrilintide held at 25 °C?

Stated plainly: dimerisation · cagrilintide · 25 °C. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody knows, I would…

peptide-stability
peptide-stability

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

832 questions
storage
storage

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

646 questions
hplc
hplc

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

466 questions
asked by thermal_mass 16k · 8 months ago
13 votes 5 answers12k views
How would I detect aspartimide formation in a tirzepatide vial without sending it to Janoshik?

Conditions: aspartimide formation · tirzepatide · Janoshik. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have already…

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,…

832 questions
harm-reduction
harm-reduction

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

445 questions
asked by rune_thoresen 14k · 2.0 years ago
13 votes0 answers12k views
Does dimerisation dominate for a GLP-1 receptor agonist held at 25 °C?

Stated plainly: dimerisation · a GLP-1 receptor agonist · 25 °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,…

832 questions
storage
storage

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

646 questions
hplc
hplc

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

466 questions
asked by n_takahashi 36k · 2.0 years ago
13 votes 5 answers12k views
Does aggregation dominate for cagrilintide held at 37 °C?

Setup, so nobody has to ask: aggregation · cagrilintide · 37 °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,…

832 questions
storage
storage

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

646 questions
hplc
hplc

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

466 questions
asked by lukas_sedlacek 17k · 21 months ago
13 votes 5 answers11k views
My mazdutide vial sat at 40 °C for seven days — is testing worth it before use?

Details up front: mazdutide · 40 °C · seven days. This is a planning question. I know what my options are; I do not know how to weigh them. What I want is the minimum…

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…

524 questions
peptide-stability
peptide-stability

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

832 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…

865 questions
asked by jana_horakova 15k · 4 months ago
13 votes 4 answers10k views
My orforglipron vial sat at 4 °C for ten days — is testing worth it before use?

Stated plainly: orforglipron · 4 °C · ten days. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

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…

524 questions
peptide-stability
peptide-stability

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

832 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…

865 questions
asked by ilaria_bertone 43k · 5 months ago
13 votes 5 answers9.5k views
How long does oral semaglutide stay within specification at 2–8 °C once reconstituted?

For reference: oral semaglutide · 2–8 °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,…

832 questions
storage
storage

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

646 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…

301 questions
asked by harriet_lonsdale 14k · 7 months ago
13 votes 5 answers8.5k views
My survodutide vial sat at minus 80 °C for five days — is testing worth it before use?

Conditions: survodutide · minus 80 °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…

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…

524 questions
peptide-stability
peptide-stability

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

832 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…

865 questions
asked by carys_meredith 17k · 8 months ago
13 votes 5 answers7.7k views
What happens to semaglutide after four weeks at room temperature in solution?

Concretely: semaglutide · four weeks · room temperature. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the…

peptide-stability
peptide-stability

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

832 questions
storage
storage

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

646 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…

301 questions
asked by assay_blank 39k · 14 months ago
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…

524 questions
peptide-stability
peptide-stability

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

832 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…

865 questions
asked by pascal_thibault 13k · 11 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,…

832 questions
storage
storage

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

646 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…

301 questions
asked by ravenna_pace 13k · 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…

646 questions
peptide-stability
peptide-stability

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

832 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…

301 questions
asked by thermal_mass 16k · 11 days ago
13 votes 5 answers6k views
How would I detect hydrolysis in a retatrutide vial without sending it to VendorInvestigate?

Numbers first: hydrolysis · retatrutide · VendorInvestigate. I would like to understand the steps well enough to explain them to someone else. I have access to 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,…

832 questions
harm-reduction
harm-reduction

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

445 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,…

832 questions
storage
storage

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

646 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…

301 questions
asked by bounty_hunter_q 18k · 1 months ago
13 votes 5 answers5.7k views
How would I detect fibrillation in an ecnoglutide vial without sending it to Medutest?

For reference: 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…

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,…

832 questions
harm-reduction
harm-reduction

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

445 questions
asked by anders_vestby 17k · 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,…

832 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…

438 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…

788 questions
asked by sinead_gaffney 14k · 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,…

832 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;…

112 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…

301 questions
asked by nominal_ten 14k · 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…

524 questions
peptide-stability
peptide-stability

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

832 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…

865 questions
asked by jana_horakova 15k · 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…

524 questions
peptide-stability
peptide-stability

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

832 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…

865 questions
asked by nynke_dekker 18k · 28 days ago