Pinealon (PIN10): form, reconstitution and storage

Form & specification

Pinealon (Glu-Asp-Arg, EDR) ships as a lyophilized powder: 10 mg of peptide in a sealed vial, purity confirmed by HPLC. The material is a white amorphous solid; at small masses the visible "cake" may be barely present, and the peptide can appear as a thin film at the bottom of the vial. This is normal and does not indicate loss of content. The product is intended strictly for research use only (RUO).

Reconstitution (chemistry)

The tripeptide is readily water-soluble thanks to its two acidic (Glu, Asp) and one basic (Arg) residues. For laboratory reconstitution, use bacteriostatic water (water with 0.9% benzyl alcohol) or sterile water for injection. Add the solvent slowly down the wall of the vial, directing the stream onto the glass rather than directly onto the powder, then swirl the vial (do not shake) until fully dissolved. Vigorous agitation creates foam and local shear that can denature the peptide. Choose the solvent volume for the target working concentration: for example, 2 mL into a 10 mg vial gives 5 mg/mL. The solution should be clear and colorless; cloudiness or flakes indicate a problem with the material or solvent.

Storage

The dry lyophilate is the most stable form: keep the sealed vial at −20 °C, protected from moisture and light; under these conditions short peptides retain integrity for a long time. Avoid repeated freeze–thaw cycles of the whole vial.

The reconstituted solution is markedly less stable: keep it at +2 to +8 °C and use within a few days. For longer storage, freeze aliquots at −20 °C or below to avoid repeated thawing. The benzyl alcohol in bacteriostatic water limits microbial growth but does not stop chemical hydrolysis of the peptide bond in aqueous medium.

Stability

The main degradation routes for aqueous solutions are hydrolysis, oxidation and microbial contamination. Stability is improved by low temperature, neutral pH, minimizing exposure to air and light, and aliquoting to reduce the number of thaw cycles. Because the peptide has no aromatic chromophores, visual inspection is limited — batch integrity is tracked analytically (HPLC, mass spectrometry).

Laboratory applications

In research, Pinealon is used as a model short peptide: in cell cultures to study resistance to oxidative stress and ROS accumulation, in biophysical peptide–DNA interaction experiments, and in work on peptidergic regulation of gene expression. Working concentrations, buffers and controls are defined by the protocol of the specific study. The material is not intended for human or animal use.