MT2 Pen

MT2 is a synthetic cyclic peptide, chemically a heptapeptide that is closed into a ring via a lactam bridge between an aspartic acid and a lysine residue. In scientific research, it is studied as a model compound for conformationally fixed peptides and for the melanocortin receptor family. This compound is offered as a 3 ml pre-filled injection pen containing 10 mg, exclusively for laboratory and research purposes.

What is MT2?

MT2 has the sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂. The ring is formed when the side-chain carboxyl group of aspartic acid forms an amide bond with the side-chain amino group of lysine. This bridge fixes the chain in a limited number of conformations, whereas a linear peptide of the same length in solution assumes a wide variety of forms.

Within the ring lies the same His-D-Phe-Arg-Trp motif that recurs throughout the entire melanocortin family. Because that motif is spatially fixed here, the complex can readily be compared with linear analogues: the difference in receptor affinity is then attributable to the conformation and not to the sequence. Additionally, the cyclization makes the chain less sensitive to exopeptidases, which makes the compound useful as a stable reference substance in analytical work.

Research areas

In a laboratory context, MT2 occurs in the following research areas, among others:

• Conformation study — NMR and circular dichroism measurements on a ring fixed via a lactam bridge.
• Receptor pharmacology — binding studies to melanocortin receptors in cell models.
• Comparative research — cyclical versus linear analogues with the same core motif.
• Enzyme stability — resistance of a closed ring to exopeptidases in buffer systems.
• Analytical method development — application as a reference standard in RP-HPLC and LC-MS.
• Stability and solubility testing — behavior at varying pH, ionic strength, and storage temperature.

Each of these applications involves controlled laboratory or preclinical model research.

MT2 within our research range

This version belongs to the line of pre-filled injection pens: compounds contained in dissolved form in a sealed cartridge, so that a researcher does not need to go through their own dissolution step. The same compound is available elsewhere in the range as freeze-dried lyophilisate in a vial. Other compounds within the pen line act on a completely different biochemical system; the form indicates nothing about the substance class.

Specifications

Shape, handling and storage

The compound is dissolved in a sealed 3 ml glass cartridge in a pen with a click mechanism. A separate dissolution step is not required with this version; the cartridge remains closed until a needle is inserted. The label includes a table showing the relationship between click settings and dispensed volume, allowing sample collections to be reproducibly recorded in a protocol.

Store the pen refrigerated between 2 and 8 °C, protected from light and in the original packaging. Handle the pen in a clean working environment, use a new sterile needle for each draw to prevent cross-contamination, and wear standard personal protective equipment. Keep the material out of reach of unauthorized persons.

Composition and lab results

The raw material used has a controlled purity of ≥ 99% (HPLC). The pen contains MT2 in a sterile aqueous base; the total amount of active substance is stated on the label.

Analysis certificates of the relevant parties are on our lab results page.

Frequently Asked Questions

Which substance class does MT2 belong to?
A synthetic cyclic peptide of seven amino acid residues. The ring is formed by a lactam bridge between the side chains of aspartic acid and lysine.

What is the use of that ring in research?
The bridge fixes the chain in a limited number of conformations. As a result, a difference in receptor affinity compared to a linear analogue is attributable to the shape of the molecule and not to the sequence of the amino acids.

In what form is the compound supplied?
As a pre-filled injection pen with a sealed 3 ml cartridge containing 10 mg. The box also contains ten sterile pen needles and alcohol wipes.

How do I store the pen?
Refrigerated between 2 and 8 °C, in a dark place and in the original packaging. Do not freeze.