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peptide-stability

Page 32 of 35 · 832 questions tagged peptide-stability.

832 questions · sorted by votes · page 32 of 35

5 votes 5 answers12k views
Is there any published stability data for orforglipron at minus 80 °C?

What I am working with: orforglipron · minus 80 °C. This is asserted often enough that I assumed it was established, and then I went looking for the source. I have…

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 marcus_thorbjorn 16k · 17 months ago
5 votes 5 answers12k views
Would you re-test survodutide after twelve weeks at 2–8 °C, or accept the original certificate?

The case in front of me: survodutide · twelve weeks · 2–8 °C. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow…

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 tabular_nums 47k · 2.1 years ago
5 votes 5 answers11k views
Is a GLP-1 receptor agonist at 10 mg/mL stable enough for two weeks of multi-withdrawal use?

Numbers first: a GLP-1 receptor agonist · 10 mg/mL · two weeks. I am asking for verification rather than opinion, ideally with something I can read myself. It is…

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 rania_haddad 17k · 12 months ago
5 votes 5 answers10k views
How many freeze-thaw cycles will dulaglutide at 3.33 mg/mL tolerate?

What I am working with: dulaglutide · 3.33 mg/mL. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the theory.…

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 area_percent 13k · 7 months ago
5 votes 5 answers9.8k views
My orforglipron vial sat at 25 °C for ten days — is testing worth it before use?

Stated plainly: orforglipron · 25 °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 aine_mulcahy 35k · 22 months ago
5 votes5 answers7.8k views
Does dimerisation produce a resolvable peak on a C18 column, or does it co-elute?

Setup, so nobody has to ask: dimerisation · a C18 column. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody knows, I…

hplc
hplc

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

466 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
peptide-stability
peptide-stability

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

832 questions
asked by label_claim 11k · 5 months ago
5 votes 5 answers7.4k views
How would I detect racemisation in a dulaglutide vial without sending it to VendorInvestigate?

Details up front: racemisation · dulaglutide · VendorInvestigate. I can find plenty of assertions about this and almost no reasoning, which is usually a sign that…

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 dermot_kiely 14k · 12 months ago
5 votes5 answers7.4k views
Is there any published stability data for semaglutide at minus 80 °C?

Concretely: semaglutide · minus 80 °C. I want to know whether there is evidence behind this or only repetition. I have checked the obvious registries and monographs…

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 fiadh_cronin 14k · 2.0 years ago
5 votes 5 answers6.3k views
How would I detect deamidation in a survodutide vial without sending it to Medutest?

The specifics, since they change the answer: deamidation · survodutide · Medutest. I have read the obvious sources and they disagree with each other, so I would…

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 Dr_Tomas_Kral 37k · 10 months ago
5 votes 2 answers5.9k views
My dulaglutide vial sat at minus 80 °C for ten days — is testing worth it before use?

Stated plainly: dulaglutide · minus 80 °C · ten days. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight,…

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 Dr_Aoife_Brennan 50k · 6 months ago
5 votes 5 answers5.1k views
How long does a GLP-1 receptor agonist stay within specification at 30 °C once reconstituted?

Numbers first: a GLP-1 receptor agonist · 30 °C. I can find plenty of assertions about this and almost no reasoning, which is usually a sign that nobody has checked.…

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 mateo_iglesias 16k · 3 months ago
5 votes5 answers4.9k views
Is minus 80 °C an acceptable storage condition for lyophilised semaglutide?

For reference: minus 80 °C · semaglutide. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has tested that", I would…

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 klara_novotna 16k · 12 months ago
5 votes0 answers4.8k views
Does surface adsorption to the vial wall lose measurable peptide?

I have the same lot stored correctly as a comparator, if a side-by-side test would help. I have worked this out and I would like someone to find the error, because 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 Dr_Idris_Coulibaly 40k · 15 months ago
5 votes0 answers4.4k views
How long does retatrutide stay within specification at 30 °C once reconstituted?

Stated plainly: retatrutide · 30 °C. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the theory. What I have…

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 loss_on_drying 47k · 2.1 years ago
5 votes5 answers4.3k views
Would you re-test oral semaglutide after ten weeks at 25 °C, or accept the original certificate?

The particulars: oral semaglutide · ten weeks · 25 °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…

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 cake_intact 18k · 3 months ago
5 votes 5 answers4.2k views
Does reconstituting oral semaglutide with bacteriostatic water change anything I should know about?

The particulars: oral semaglutide · bacteriostatic water. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. I…

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,…

330 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
peptide-stability
peptide-stability

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

832 questions
asked by micron22 36k · 13 days ago
5 votes5 answers4.1k views
Does mazdutide adsorb measurably to the vial wall at 4 mg/mL?

What I have: mazdutide · 4 mg/mL. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would rather…

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 kofi_mensah 12k · 10 months ago
5 votes 5 answers2.8k views
Would you re-test tirzepatide after three weeks at room temperature, or accept the original certificate?

For reference: tirzepatide · three weeks · room temperature. I am at the decision point and I would rather think it through than improvise. I would rather spend money…

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 nominal_ten 14k · 2 months ago
5 votes0 answers1.9k views
My a GLP-1 receptor agonist vial sat at 2–8 °C for seven days — is testing worth it before use?

Details up front: a GLP-1 receptor agonist · 2–8 °C · seven days. This is a planning question. I know what my options are; I do not know how to weigh them. What 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 noor_alhassan 15k · 9 months ago
5 votes 3 answers1.7k views
Would you re-test survodutide after four weeks at room temperature, or accept the original certificate?

The case in front of me: survodutide · four weeks · room temperature. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months…

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 mass_shift_18 14k · 4 months ago
5 votes0 answers1.7k views
What happens to a GLP-1 receptor agonist after sixteen weeks at minus 80 °C in solution?

Numbers first: a GLP-1 receptor agonist · sixteen weeks · minus 80 °C. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware this may…

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 · 2 months ago
4 votes 5 answers19k views
Does hydrolysis of dulaglutide at minus 20 °C show up as a loss of content or of purity?

Details up front: hydrolysis · dulaglutide · minus 20 °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
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 priya_menon 11k · 19 months ago
4 votes5 answers16k views
Does oxidation dominate for liraglutide held at 2–8 °C?

Conditions: oxidation · liraglutide · 2–8 °C. This is one of those things that everyone repeats and nobody derives. This matters practically, not just academically,…

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 ilaria_bertone 43k · 14 months ago
4 votes 5 answers12k views
Would you re-test retatrutide after two weeks at 2–8 °C, or accept the original certificate?

Stated plainly: retatrutide · two weeks · 2–8 °C. I am trying to build something sustainable rather than something thorough that I will abandon. I have already…

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 low_dead_space 42k · 8 months ago