Retatrutide 40mg Vial Lab Results — HPLC, Endotoxin & TFA Verification

Batch RET-20-V-2604-001 is the shared retatrutide lot behind both vial formats — the 40mg bulk vial on this page and the smaller 10mg vial. The Janoshik workup is identical for both SKUs because they are filled from the same lot; what differs is fill quantity, not synthesis. The panel covers four distinct measurements, each on a separate certificate.

HPLC purity (reverse-phase, C18). The retatrutide fraction is separated from peptide-related impurities — truncated sequences, deletion variants, synthesis byproducts — on a C18 stationary phase, then quantified against the reference retention time for the parent peptide (LY-3437943, CAS 2381089-83-2). The reported 99.741% figure is the area-under-the-curve percentage for the parent peak, normalised against the sum of all peptide-related peaks. Assay measured 20.92 mg retatrutide per vial of fill weight, confirming the labelled quantity for the lot.

Heavy metals (ICP-MS). The four heavy-metal contaminants of pharmacopoeial interest — arsenic, cadmium, lead, mercury — were each measured by ICP-MS and reported as not detected at the relevant limits of quantification. On a lyophilized vial, any heavy-metal trace is concentrated rather than diluted, which is why the test matters more on the vial format than on a pre-formulated pen.

Residual TFA. Trifluoroacetic acid is a common counter-ion in solid-phase peptide synthesis and a frequent residual on insufficiently exchanged peptide lots. Janoshik measured residual TFA and reported it as not detected. For triple-agonist work where receptor binding assays are downstream, removing TFA matters because it can interfere with cell-based readouts.

Bacterial endotoxin (LAL). The Limulus Amebocyte Lysate (LAL) test quantifies bacterial endotoxin — lipopolysaccharide fragments that can persist through synthesis and fill steps. RET-20-V-2604-001 measured 1.449 EU/Vial. Endotoxin is the panel most directly relevant to in-vitro cell work that wants to control for confounding immune signalling; publishing the number on a research-use vial is unusual and is what makes the vial line the documentation-first option in the Remy range.

The 40mg vial is the bulk format in the vial line. For extended research protocols — longer in-vitro time courses, repeated assay runs, multi-arm experiments where the same lot needs to back several conditions — using one larger vial rather than four 10mg vials reduces per-vial reconstitution variance and keeps the published Janoshik panel consistent across the work. Because both formats are filled from the same retatrutide lot, the 99.741% HPLC, 20.92 mg assay, undetectable heavy metals and TFA, and 1.449 EU/Vial endotoxin numbers all carry across.

Retatrutide is a triple-receptor agonist engaging GIP, GLP-1, and glucagon receptors with a single molecule. Triple-agonist potency is highly sensitive to sequence integrity: any truncation or deletion variant alters receptor binding for at least one of the three pathways, which is what makes HPLC purity verification meaningful. At 99.741% HPLC, RET-20-V-2604-001 sits in the same band as the rest of the Remy Retatrutide line (30mg pen 99.262%, 20mg pen 99.841%) — inter-batch variation of 0.1–0.6% is normal and reflects analytical precision rather than systematic differences in synthesis. The bulk vial extends that comparability across longer studies without batch transitions in the middle.