RP_C18
Twenty-two years on reverse-phase methods. If your purity number has no method attached, it is not a number.
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Top answers
156What counter-ion should I expect on a TFC tirzepatide lot?accepted · answered 9 Aug 2024143How can a vial be 99% pure by HPLC and still contain under 7 mg of a nominal 10 mg?accepted · answered 6 May 2025130Has anyone independently verified a Homopeptide oral semaglutide batch COA?accepted · answered 18 Jun 2025107What does a 96.4% purity with a batch certificate attached let me conclude?accepted · answered 21 May 2024102How does retatrutide behave on a C18 column compared to survodutide?answered 6 Oct 2024100Is 98.8% a realistic purity ceiling for mazdutide given its chain length?accepted · answered 12 Aug 202499Why would Medutest report 97.1% where the supplier certificate says something higher?accepted · answered 29 Jan 202697Does aspartimide formation produce a resolvable peak on a C4 column, or does it co-elute?accepted · answered 7 Sept 2025
Top questions
36My a GLP-1 receptor agonist vial sat at 4 °C for twenty-eight days — is testing worth it before use?3 answers, accepted · asked 17 May 202530Does racemisation dominate for retatrutide held at 4 °C?5 answers · asked 9 May 202522What is the dead-space loss per draw with an 18G drawing needle at 1 mg/mL?0 answers · asked 16 Apr 202620If I reconstitute a 15 mg vial with 2 mL of phosphate-buffered diluent, what concentration do I end up with?5 answers, accepted · asked 19 Nov 202518What did the placebo arm of SURMOUNT-4 report for nausea?1 answer · asked 29 Nov 202517How do I check that two QYB lots of semaglutide agree on content assay?5 answers, accepted · asked 22 Jan 202614What is the reported incidence of dizziness on tirzepatide in SURPASS-2?5 answers · asked 22 Oct 202513Can I reconstitute mazdutide at 6.67 mg/mL and still measure a small dose accurately?4 answers, accepted · asked 11 Dec 2025