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jo_vandeberg

Member for 1 yearsMember since 10 Sept 2025Last seen 30 days agoFrom Bilbao, ES

I only post when I have a certificate to attach.

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52 answers · 10 accepted · highest score 119

119What did REDEFINE 1 report against each of its component arms?accepted · answered 12 Jun 2024 · cagrisema, clinical-trials, amylin 88Is there an honest apples-to-apples comparison of the STEP and SURMOUNT headline results?accepted · answered 16 Apr 2025 · semaglutide, tirzepatide, clinical-trials 74How comparable are survodutide and retatrutide on the evidence available?accepted · answered 8 Jan 2026 · clinical-trials, semaglutide, tirzepatide 67Where does an "EU/mg" endotoxin limit come from, and is a spec of 10 EU/mg tight or loose?answered 5 Sept 2025 · endotoxin, coa, batch-testing 64How do I tell headache from an energy deficit on 1,100 kcal a day?answered 7 Apr 2025 · fatigue, nutrition, electrolytes 64Is STEP 5 a fair comparison of a GLP-1 receptor agonist against its comparator arm?accepted · answered 31 Aug 2024 · clinical-trials, semaglutide, tirzepatide 59How does survodutide behave on a C4 column compared to retatrutide?accepted · answered 28 Mar 2025 · hplc, purity, reference-standard 58Is SURMOUNT-5 a fair comparison of tirzepatide against its comparator arm?answered 3 Mar 2025 · clinical-trials, semaglutide, tirzepatide 50Does nausea at week ten of retatrutide usually resolve without a dose change?answered 12 Nov 2025 · nausea, titration, retatrutide 50What is the reported incidence of early satiety on tirzepatide in SURPASS-2?answered 14 Dec 2024 · gi-side-effects, clinical-trials, tirzepatide 49How many freeze-thaw cycles will semaglutide at 3.33 mg/mL tolerate?answered 28 Mar 2024 · freeze-thaw, peptide-stability, storage 46How do I write up a PeptideMeter result on tirzepatide so it is useful to others?accepted · answered 1 Jun 2026 · batch-testing, coa, harm-reduction 44How does mazdutide behave on a C8 column compared to cagrilintide?answered 3 Dec 2025 · hplc, purity, reference-standard 42What does the mechanism of oral semaglutide predict that SOUL did not test?answered 12 Jul 2024 · glp1-mechanism, clinical-trials, gip-receptor 40What is the reported incidence of nausea on tirzepatide in SURMOUNT-1?answered 15 Oct 2024 · nausea, clinical-trials, tirzepatide 40What is the reported incidence of vomiting on retatrutide in TRIUMPH-3?answered 26 Apr 2024 · vomiting, clinical-trials, retatrutide 38Is STEP 4 a fair comparison of a GLP-1 receptor agonist against its comparator arm?accepted · answered 14 Feb 2025 · clinical-trials, semaglutide, tirzepatide 36Is headache on tirzepatide dose-dependent or dose-rate dependent?accepted · answered 22 Jul 2026 · titration, harm-reduction, tirzepatide 33Is SURMOUNT-5 a fair head-to-head comparison?answered 28 Apr 2025 · tirzepatide, semaglutide, clinical-trials 32How comparable are ecnoglutide and retatrutide on the evidence available?answered 15 Apr 2026 · clinical-trials, semaglutide, tirzepatide 30How comparable are cagrilintide and retatrutide on the evidence available?answered 24 Sept 2024 · clinical-trials, semaglutide, tirzepatide 29Why is a fixed-ratio co-formulation not the same as two separate injections?answered 27 Jul 2026 · cagrisema, amylin, semaglutide 28How comparable are a GLP-1 receptor agonist and semaglutide on the evidence available?answered 20 Apr 2025 · clinical-trials, semaglutide, tirzepatide 27How do I read a tirzepatide chromatogram from PeptideMeter beyond the headline number?answered 21 Sept 2025 · hplc, purity, coa 25What is the reported incidence of vomiting on tirzepatide in SURMOUNT-4?answered 23 May 2025 · vomiting, clinical-trials, tirzepatide 24Is STEP 5 a fair comparison of semaglutide against its comparator arm?answered 8 Apr 2025 · clinical-trials, semaglutide, tirzepatide 22How comparable are a GLP-1 receptor agonist and tirzepatide on the evidence available?answered 13 Aug 2024 · clinical-trials, semaglutide, tirzepatide 21How comparable are dulaglutide and liraglutide on the evidence available?accepted · answered 10 Jul 2026 · clinical-trials, semaglutide, tirzepatide 21How does survodutide behave on a C4 column compared to tirzepatide?answered 1 Jun 2024 · hplc, purity, reference-standard 21How many vial-days does a 2.5 mg vial give at 2.5 mg/mL on a weekly schedule?answered 21 Apr 2025 · dosing-math, cost-analysis, diluent-volume 17How would I detect racemisation in a retatrutide vial without sending it to VendorInvestigate?answered 6 Jun 2025 · vial-inspection, peptide-stability, harm-reduction 17What should I make of an oral semaglutide documentation package that has no chromatogram?answered 6 Jun 2025 · coa, vendor-vetting, batch-testing 16Does oxidation of liraglutide at 37 °C show up as a loss of content or of purity?answered 30 Oct 2025 · peptide-stability, content-assay, purity 15Is early satiety on tirzepatide dose-dependent or dose-rate dependent?answered 8 May 2026 · gi-side-effects, titration, tirzepatide 13How comparable are ecnoglutide and mazdutide on the evidence available?answered 18 Mar 2026 · clinical-trials, semaglutide, tirzepatide 13How do I reconcile 97.9% from Medutest with 98.4% from the supplier?answered 17 Jul 2026 · purity, batch-testing, coa 13Is a 99.4% result from Janoshik comparable to 97.1% from Medutest?answered 17 Apr 2025 · purity, batch-testing, reference-standard 11Does a phase-change pack hold a dulaglutide shipment for fourteen days in transit?answered 25 Mar 2025 · cold-chain, international-shipping, storage 9Has anyone independently verified a Homopeptide liraglutide batch COA?answered 27 May 2026 · vendor-vetting, coa, batch-testing 9How much of the gross mass of a 2.5 mg tirzepatide vial is actually peptide?answered 4 Aug 2024 · content-assay, water-content, acetate-content 9What is the reported incidence of nausea on retatrutide in TRIUMPH-3?answered 15 Nov 2024 · nausea, clinical-trials, retatrutide 8How does liraglutide behave on a wide-pore C18 column compared to retatrutide?answered 3 Dec 2025 · hplc, purity, reference-standard 7How comparable are dulaglutide and mazdutide on the evidence available?answered 2 Aug 2025 · clinical-trials, semaglutide, tirzepatide 7How does semaglutide behave on a C4 column compared to tirzepatide?answered 10 Dec 2025 · hplc, purity, reference-standard 7How would I detect oxidation in a tirzepatide vial without sending it to Janoshik?answered 25 Oct 2025 · vial-inspection, peptide-stability, harm-reduction 7What does a Karl Fischer water content test add for tirzepatide that a purity figure does not?answered 22 Nov 2025 · content-assay, purity, coa 6Is SURMOUNT-2 a fair comparison of tirzepatide against its comparator arm?answered 5 Apr 2025 · clinical-trials, semaglutide, tirzepatide 5Is 60 mg in 2.5 mL of bacteriostatic water a sensible presentation for tirzepatide?accepted · answered 17 Dec 2025 · diluent-volume, reconstitution, dosing-math 4Is STEP 3 a fair comparison of a GLP-1 receptor agonist against its comparator arm?answered 6 Aug 2025 · clinical-trials, semaglutide, tirzepatide 1How does retatrutide behave on a C18 column compared to survodutide?answered 28 Oct 2024 · hplc, purity, reference-standard -1Is BCH worth the price difference against GL Biochem (Shanghai) on measured results?answered 11 Jul 2026 · vendor-comparison, cost-analysis, batch-testing -1What would you ask Qingdao Saber Technology before a first order that they cannot fake?answered 24 Dec 2024 · vendor-vetting, coa, batch-testing

Top tags

tirzepatide32 posts clinical-trials28 posts semaglutide26 posts coa15 posts batch-testing14 posts purity14 posts retatrutide12 posts harm-reduction8 posts

Sigma-Aldrich

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Tags

storage

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

701 questionslean-mass127

lean-mass

Lean body mass as measured rather than assumed: what DEXA, BIA and air-displacement plethysmography each actually estimate, the body-composition…

127 questionsdead-space117

dead-space

The volume trapped in the syringe hub and needle after the plunger bottoms out. It is small in absolute terms and large as a fraction of a small…

117 questionsamylin237

amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questionsecnoglutide223

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 questionscontent-assay476

content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questionssemaglutide470

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 questionsdose-escalation103

dose-escalation

The decision to move up a step: what evidence supports a four-week interval, what happens when you compress it, and how trial protocols handled…

103 questionstirzepatide370

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 questionsresearch-use-only95

research-use-only

What "for research use only" means as a legal and practical designation: not approved for human use, no pharmacopoeial release testing, no…

95 questionscoa771

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 questionsretatrutide251

retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

251 questionsinjection-technique96

injection-technique

Technique questions: angle, pinch versus flat, aspiration, injection speed, air bubbles, and the handling steps that determine whether you deliver…

96 questionsdulaglutide200

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 questionsreconstitution313

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 questionsliver-enzymes91

liver-enzymes

ALT, AST, GGT and ALP: what they do and do not indicate about hepatic fat, why enzymes are a poor surrogate for histology, and where non-invasive…

91 questionsgi-side-effects162

gi-side-effects

The gastrointestinal cluster as a whole - nausea, vomiting, diarrhoea, constipation, reflux, early satiety - with trial incidence rates, dropout…

162 questionsvendor-comparison388

vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

388 questionsglp1-mechanism132

glp1-mechanism

Receptor-level pharmacology: GLP-1R as a class B GPCR, cAMP and PKA signalling, biased agonism, internalisation and resensitisation, and the…

132 questionscost-analysis260

cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 questionsa1c122

a1c

Glycated haemoglobin as a ninety-day glycaemic average: what a change of half a point means, why it lags, and the conditions under which it…

122 questionshplc503

hplc

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

503 questionssurvodutide225

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 questionspeptidemeter107

peptidemeter

PeptideMeter, an independent peptide analytics and vendor-rating service. Use this tag for its published datasets, its rating methodology, and how…

107 questionsinternational-shipping471

international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

471 questionsoral-glp1219

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

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Questions5.2k

Answers20k

Accepted3.1k

Unanswered739

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