Articles

What the HPLC purity % on a peptide COA really measures — area normalization, and why purity is not content, identity, or sterility.

How semaglutide and tirzepatide really differ — one incretin receptor versus two, and what the head-to-head trials show.

What a GPCR is and why it matters for peptides: the seven-transmembrane relay, the G-protein cycle, the four G-alpha families, and which peptide receptors are (and are not) GPCRs.

How research peptides are actually made: the solid-phase synthesis cycle, Boc vs Fmoc, TFA salts, and why the crude product needs HPLC and a COA.

Peptides vs small molecules: how they differ in size, specificity, oral bioavailability, half-life, immunogenicity and manufacturing — and why peptides come in vials.

Tesamorelin side effects, from the FDA-approved Egrifta label: injection-site reactions, joint pain, IGF-1 and glucose changes, antibodies, and contraindications.

Constitutive activity is agonist-independent receptor signaling. Here is what it means, why the ghrelin receptor is ~50% “on” with no ligand, and why it matters.

What is actually known about the side effects of immune peptides LL-37, KPV, and thymalin — and why product quality is the risk you can verify.

What FDA 503A categories mean, why so many research peptides are Category 2, and what the 2026 changes and July PCAC meeting could bring.

Many peptide “studies” have only four to twelve people. The rule of three explains why “no side effects reported” in a tiny trial tells you almost nothing about safety.