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Journal

Research notes, written in long-form.

GLP pathway12 min read
April 08, 2026

What the Retatrutide Phase 2 data actually showed.

Jastreboff et al. 2023 was the first head-on look at a triple-receptor agonist in humans. We read through what the trial actually demonstrated — and what people are reading into it that the trial didn't measure.

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Analytical methods9 min read
March 27, 2026

HPLC and mass spec — what each one actually proves.

A chromatogram tells you a peak is pure. Mass spec tells you that peak is the right molecule. They answer different questions, and a COA showing only one of them is telling you less than it looks like.

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Field guide7 min read
March 14, 2026

Peptide storage: a practical guide to reconstitution and drift.

The difference between a peptide that works in a study and one that doesn't is often chain-of-custody. Bacteriostatic water, 2–8°C, freeze–thaw cycles — the variables that quietly degrade results.

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Regulatory11 min read
February 28, 2026

What “research use only” actually covers in 2026.

The RUO framework predates most of the brands invoking it. A plain-language read on where the line actually sits in 21 CFR 312 and the FDA's enforcement posture — what it covers, what it doesn't, and where most peptide sellers are technically out of bounds.

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Longevity14 min read
February 17, 2026

NAD+ research, past the sirtuin headline.

The NAD+ conversation got compressed into a sirtuin pitch about a decade ago, but the actual research has been broader the whole time — DNA repair, PARP signaling, CD38, mitochondrial bioenergetics. A survey of where the field actually is.

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How we operate6 min read
January 30, 2026

The test-or-refund guarantee, and why we offer it.

Anyone can call themselves verified. We offer something harder — if your own lab disagrees with our published spec, we cover the test fee plus your full refund. Skin in the game beats marketing claims.

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Metabolic pathway12 min read
April 22, 2026

The half-life that changed metabolic medicine.

Native human GLP-1 has a half-life of about two minutes. Two small chemical changes — a position-8 swap and an eighteen-carbon fatty-acid tail that binds albumin — extended that to 165 hours, and an entire decade of metabolic medicine reorganized around the result.

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Metabolic pathway12 min read
April 22, 2026

Two receptors, one peptide, and the geometry of fat loss.

For two decades, GIP was considered the lesser sibling of GLP-1. Tirzepatide was designed against that consensus — and the trials that followed kept producing benefits the metabolic literature had not predicted.

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Growth-hormone fragment11 min read
April 22, 2026

The tail of a hormone, without the hormone itself.

AOD-9604 is, in a sense, growth hormone's lipid-handling instruction without growth hormone itself. The clinical story in obesity was modest. The afterlife in cartilage repair and metabolic-syndrome work has been more interesting.

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Growth-hormone axis12 min read
April 22, 2026

The pulsatile hormone the aging body forgets to send.

The pituitary releases growth hormone in pulses. The amplitude and frequency of those pulses fall with age. Tesamorelin restores the upstream signal — and a 2012 University of Washington trial showed something unexpected about cognition along the way.

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Mitochondrial-derived peptides9 min read
April 22, 2026

MOTS-c: the peptide your mitochondria write when you exercise.

Discovered in 2015 by Pinchas Cohen's group at USC, MOTS-c is a peptide encoded inside the mitochondrial 12S rRNA gene. A decade of research has framed it as an exercise-mimicking signal — and 2024 work pushes it past metabolism into membrane repair.

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Metabolic enzymology9 min read
April 22, 2026

5-Amino-1MQ: the enzyme inhibitor that thinks it's exercise.

Most metabolic drugs work by adding something. 5-Amino-1MQ is interesting because it works by subtraction — sitting in the active site of NNMT, blocking the methyl group from being transferred, and letting the cell hold on to two molecules it ordinarily would have lost.

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Neurorestoration10 min read
April 08, 2026

Cerebrolysin: the Austrian neuropeptide with forty years of stroke data.

Cerebrolysin is the kind of compound American pharmacology textbooks tend to omit. It has been on the European market for four decades, sits in the formularies of more than fifty national health systems, and has been the subject of more than a hundred randomized trials.

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Immune modulation10 min read
April 01, 2026

Thymosin Alpha-1: an Italian immunopeptide and the trial that rewrote its story.

Thymosin Alpha-1 has been studied for half a century, approved in dozens of countries, and used in tens of millions of patient-courses. What it does, broadly, is shift the immune set-point — lifting where suppressed, dampening where hyperactive.

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Compound study · Selank9 min read
April 22, 2026

Selank: the Soviet anxiolytic that doesn't sedate.

An anxiolytic that, in head-to-head comparisons against medazepam, produces a similar reduction in symptom severity without the cognitive blunting, the rebound, or the dependence that defines the benzodiazepine class. The bulk of the file is in Russian.

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Compound study · DSIP9 min read
April 22, 2026

DSIP: a 1977 Swiss discovery that still hasn't been fully explained.

Most peptides have a clean mechanism story. DSIP — delta sleep-inducing peptide — has resisted that narrative for nearly half a century. The molecule clearly does something. What it does not do is bind in a way anyone has cleanly resolved.

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Compound study · Kisspeptin-109 min read
April 22, 2026

Kisspeptin-10: the molecule named after a chocolate bar.

In 1996 a group at Penn State College of Medicine in Hershey, Pennsylvania, cloned a metastasis-suppressor gene. They needed a symbol. They picked KISS1 — a wink to Hershey's most famous export. When the gene's peptide product turned out to be the master regulator of mammalian reproduction, the name stuck.

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Compound study · HCG9 min read
April 22, 2026

HCG: the pregnancy hormone doing double duty in men's medicine.

It is not often that a hormone discovered in pregnant women's urine becomes a workhorse drug in men's reproductive medicine. HCG earned that strange double life through a quirk of molecular evolution: the β-subunit of HCG and the β-subunit of LH are roughly 85 percent identical.

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Compound profile · Recovery9 min read
April 22, 2026

TB-500 and the strange afterlife of an actin-binding peptide.

The 1981 paper had been about a thymic immune factor. The 1991 paper was about cytoskeletal mechanics. They were the same molecule. Three decades later, the 2024 work suggests it's also doing something with macrophage resolution that nobody had labeled.

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Compound profile · GH axis8 min read
April 23, 2026

CJC-1295 and the engineering problem GHRH was never going to solve.

Native GHRH has a half-life of roughly 7 minutes. CJC-1295 was designed to bind serum albumin in vivo, extending half-life to 5.8–8.1 days. The molecule was not made longer-acting; its carrier was. The peptide became a passenger on a protein with a 21-day clearance time.

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Compound profile · GH axis8 min read
April 24, 2026

Ipamorelin and the engineering ideal of a clean signal.

By 1998, several synthetic GH secretagogues were in clinical development with a problematic feature: they released growth hormone, but they also released cortisol, prolactin, ACTH, and aldosterone. The signal was dirty. Ipamorelin was the answer.

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