Every research peptide supplier says its products are tested. The more useful question is: tested by whom? A result produced by the seller and a result produced by an independent laboratory may look identical on paper, but they carry very different weight. This article explains what third-party testing is, what it can and cannot prove, […]

Search any research peptide catalog and you will see the same phrase over and over: “99%+ purity.” It sounds definitive. But purity is a number that depends on how it was measured, what was counted, and what was left out. This article explains what a purity claim actually tells you, the common ways it gets […]

When a research peptide is described as “99% pure,” what does that actually mean? The number usually comes from a single technique, high-performance liquid chromatography (HPLC), and it answers only part of the question. A second technique, mass spectrometry (MS), answers a different one. Understanding what each method measures, and what it cannot, helps you […]