Selank is a short synthetic peptide that is structurally based on a natural immune peptide fragment. The strongly basic character of the sequence determines its behaviour in chromatography.<\/p>\n
Selank is a heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. The first four amino acids correspond to the tetrapeptide tuftsin, a fragment derived from immunoglobulin G. Appended is the C-terminal tripeptide Pro-Gly-Pro, which increases stability against peptidases. The molecular mass is approximately 752 Da.<\/p>\n
With lysine and arginine the sequence contains two strongly basic residues as well as three proline residues. Commercial material is usually present as a lyophilised white powder in acetate or trifluoroacetate salt form. The salt form influences the weighed portion and the calculation of the peptide content and should therefore be documented.<\/p>\n
Selank is described in the neuroscience research literature, predominantly in publications from the Russian-speaking world, and is frequently treated there together with Semax. In the European Union there is no marketing authorisation as a medicinal product. For laboratory contexts it is relevant that the available literature relates to different preparations and manufacturing routes; comparability between batches can only be established via documented analytical data, not via the substance designation.<\/p>\n
Selank contains no aromatic amino acids. Detection at 254 or 280 nm is therefore unsuitable; recording takes place exclusively via the absorption of the peptide bond at 214 to 220 nm. A purity figure without the detection wavelength named cannot be assessed for this peptide.<\/p>\n
With heptapeptides, deletion sequences are usually well separated chromatographically from the main peak. More relevant in practice with Selank is the question of whether the gradient separates at all in the early elution range, since polar by-products and residual salts also appear there. The three proline residues can also cause cis\/trans isomerism and thereby peak broadening or double peaks, which must not be confused with an impurity. In every case an area-percent value describes only the proportion of the detected signal, not the peptide content of the sample.<\/p>\n
Analytical documentation is only meaningful with a batch reference, method description, gradient conditions, detection wavelength and the associated raw data. Without this information a document cannot be assigned to a specific sample. Notes on the structure and reading of such documents can be found in the linked resources.<\/p>\n
Lyophilised peptides are considerably more stable in the dry, light-protected state than in solution. For laboratory stocks, storage at minus 20 degrees Celsius, protection from moisture and light as well as avoiding repeated freeze-thaw cycles are common practice. Strongly hygroscopic salt forms take up moisture at room temperature, which can falsify the weighed portion. These details concern exclusively the handling of laboratory substances.<\/p>\n
This page serves exclusively as scientific and analytical information. It contains no dosage, application or treatment instructions. Products are not intended for use in humans or animals.<\/em><\/p>","protected":false},"excerpt":{"rendered":" Selank ist ein kurzes synthetisches Peptid, das strukturell auf einem nat\u00fcrlichen Immunpeptid-Fragment aufbaut. Der stark basische Charakter der Sequenz bestimmt sein Verhalten in der Chromatographie. Was ist Selank? Selank ist ein Heptapeptid mit der Sequenz Thr-Lys-Pro-Arg-Pro-Gly-Pro. Die ersten vier Aminos\u00e4uren entsprechen dem Tetrapeptid Tuftsin, einem aus dem Immunglobulin G abgeleiteten Fragment. Angeh\u00e4ngt ist das C-terminale […]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":462,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-500","page","type-page","status-publish","hentry"],"yoast_head":"\n