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peptide-stability

Page 33 of 35 · 832 questions tagged peptide-stability.

832 questions · sorted by votes · page 33 of 35

4 votes 5 answers12k views
Is semaglutide at 2 mg/mL stable enough for three weeks of multi-withdrawal use?

Concretely: semaglutide · 2 mg/mL · three weeks. I want to know whether there is evidence behind this or only repetition. I have checked the obvious registries and…

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 felix_araya 17k · 10 months ago
4 votes 5 answers9.3k views
What happens to retatrutide after two weeks at minus 20 °C in solution?

Stated plainly: retatrutide · two weeks · 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,…

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 claudia_ferrante 46k · 8 months ago
4 votes 5 answers8.7k views
How long does mazdutide stay within specification at 2–8 °C once reconstituted?

Numbers first: mazdutide · 2–8 °C. I would like to understand the steps well enough to explain them to someone else. I have access to a refrigerator with a logger and…

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 lyoph_cake 95k · 6 months ago
4 votes 5 answers5.9k views
Why does dimerisation accelerate at 37 °C rather than proceeding linearly?

Setup, so nobody has to ask: dimerisation · 37 °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 siobhan_deasy 16k · 10 months ago
4 votes 5 answers5.8k views
Is 30 °C an acceptable storage condition for lyophilised semaglutide?

For reference: 30 °C · semaglutide. Somebody stated this to me confidently and I would like to check it before repeating it. I would accept a well-reasoned negative…

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 swab_and_wait 15k · 2 months ago
4 votes 5 answers5.1k views
Does aggregation of mazdutide at room temperature show up as a loss of content or of purity?

Setup, so nobody has to ask: aggregation · mazdutide · room temperature. The empirical answer seems settled. The explanation does not. If the honest answer is that…

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 ravi_pillai 16k · 2 months ago
4 votes 5 answers5.1k views
How long does mazdutide stay within specification at 40 °C once reconstituted?

What I have: mazdutide · 40 °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,…

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 vial_five 15k · 2 months ago
4 votes 5 answers4.8k views
My liraglutide vial sat at 37 °C for three days — is testing worth it before use?

The particulars: liraglutide · 37 °C · three days. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with explicit…

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 elke_brunner 14k · 3 months ago
4 votes5 answers4.7k views
Would you re-test semaglutide after four weeks at 25 °C, or accept the original certificate?

The case in front of me: semaglutide · four weeks · 25 °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 rania_haddad 17k · 20 days ago
4 votes5 answers4.5k views
How long does mazdutide stay within specification at room temperature once reconstituted?

What I have: mazdutide · room temperature. 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,…

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 triple_agonist_q 37k · 5 months ago
4 votes 5 answers4.5k views
My orforglipron vial sat at 4 °C for forty-two days — is testing worth it before use?

What I am working with: orforglipron · 4 °C · forty-two days. I am trying to build something sustainable rather than something thorough that I will abandon. I have…

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 seven_day_half 16k · 10 months ago
4 votes0 answers4.2k views
Does fibrillation of semaglutide at 25 °C show up as a loss of content or of purity?

The specifics, since they change the answer: fibrillation · semaglutide · 25 °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,…

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 fibre_or_fragment 12k · 2.1 years ago
4 votes0 answers4.1k views
What happens to cagrilintide after six weeks at 2–8 °C in solution?

Numbers first: cagrilintide · six weeks · 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…

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 cap_the_luer 15k · 19 months ago
4 votes0 answers3.4k views
Is there any published stability data for dulaglutide at 37 °C?

Stated plainly: dulaglutide · 37 °C. This is asserted often enough that I assumed it was established, and then I went looking for the source. I have searched 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
clinical-trials
clinical-trials

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

913 questions
asked by kwn_analytical 89k · 10 months ago
4 votes 2 answers3.3k views
Does dimerisation of mazdutide at 4 °C show up as a loss of content or of purity?

Setup, so nobody has to ask: dimerisation · mazdutide · 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
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 Dr_Otto_Lindqvist 38k · 12 months ago
4 votes 1 answer1.3k views
What happens to mazdutide after six weeks at 30 °C in solution?

Details up front: mazdutide · six weeks · 30 °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…

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 ines_delacruz 16k · 3 months ago
4 votes0 answers847 views
Does racemisation dominate for retatrutide held at 25 °C?

What I have: racemisation · retatrutide · 25 °C. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware this may have a boring answer.…

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 ines_delacruz 16k · 5 months ago
3 votes 5 answers12k views
Why does hydrolysis accelerate at 37 °C rather than proceeding linearly?

Numbers first: hydrolysis · 37 °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,…

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 mass_shift_18 14k · 13 months ago
3 votes 5 answers12k views
How many freeze-thaw cycles will cagrilintide at 4 mg/mL tolerate?

What I have: cagrilintide · 4 mg/mL. I would like to understand the steps well enough to explain them to someone else. I have access to a refrigerator with a logger…

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…

55 questions
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
asked by assay_blank 39k · 16 months ago
3 votes 5 answers9.2k views
What happens to cagrilintide after sixteen weeks at 2–8 °C in solution?

Numbers first: cagrilintide · sixteen weeks · 2–8 °C. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware this may have a boring…

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 otto_brenner 19k · 13 months ago
3 votes 5 answers7.9k views
Would you re-test mazdutide after sixteen weeks at 4 °C, or accept the original certificate?

What I have: mazdutide · sixteen weeks · 4 °C. I would rather over-plan the first cycle and simplify later. I am prepared to do the work if someone can tell me which…

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 carys_meredith 17k · 10 months ago
3 votes 5 answers5k views
Is 30 °C an acceptable storage condition for lyophilised ecnoglutide?

The specifics, since they change the answer: 30 °C · ecnoglutide. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has…

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 lane_transit 42k · 33 days ago
3 votes 5 answers4.7k views
Is liraglutide at 10 mg/mL stable enough for four weeks of multi-withdrawal use?

The specifics, since they change the answer: liraglutide · 10 mg/mL · four weeks. Somebody stated this to me confidently and I would like to check it before repeating…

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 gel_pack_warm 13k · 9 months ago
3 votes 5 answers4.2k views
Does ecnoglutide adsorb measurably to the vial wall at 3.33 mg/mL?

Concretely: ecnoglutide · 3.33 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…

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 threadlock7 14k · 2 months ago