A practical reference on tuftsin: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-11-14. Anything still debated is marked as such rather than presented as settled.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Reported pharmacological effects center on reduced anxiety-like behavior in animal models and on measures of memory and learning. Proposed contributing mechanisms include modulation of GABAergic signaling, shifts in monoamine turnover, and changes in the activity of enzymes that degrade neuropeptides. Effects on the expression of genes linked to neuroplasticity have also been described. No single molecular target is widely accepted, and whether the behavioral findings arise from one pathway or several remains an open question.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Reversed-phase HPLC retention time versus reference standard | Retention depends on column, gradient, and ion-pairing agent |
| Mass confirmation | Electrospray or MALDI mass spectrometry | Doubly protonated ion near m/z 377 is consistent with about 752 Da |
| Typical purity specification | 95 percent or higher by chromatographic peak area | Lower values suggest truncated or modified peptide species |
| Storage of lyophilized powder | -20 °C, desiccated, protected from light | Powder tolerates long storage better than solution |
| Storage of solution | 2-8 °C for short periods | Freeze-thaw cycling promotes aggregation and surface adsorption |
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
The primary structure of Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, corresponding to the molecular formula C33H57N11O9 and a monoisotopic mass of roughly 751.9 daltons. The N-terminal threonine and the arginine residue in the fourth position are shared with tuftsin, which carries the sequence Thr-Lys-Pro-Arg. The three additional residues at the C-terminus, Pro-Gly-Pro, extend the chain and are associated with greater resistance to enzymatic degradation. This extension also separates Selank from the shorter parent peptide.
== Synthesis of antamanide == The first synthesis of this natural product was in 1969. Since then many different types of synthetic routes have been used to make the compound. One common method for the synthesis of the linear form of antamanide is the excluded protecting group (EPG) method. In this process, each of the peptides in the cycle are connected to one another one at a time by coupling reactions. In this case, first a valine residue is protected by the Fmoc protecting group to protect the amine group in the amino acid. The peptide is then coupled to an OICh (cholestene) group. OICh is a protecting group used to protect the carboxyl group in the amino acid. Next, the Fmoc group is removed to make an amine by using diethyl amine (Et2N). The next amino acid in the peptide chain is then added to the amine in the same type of coupling reaction, and the process is repeated until the chain form of the cycle is complete. The OICh group is removed by using powdered zinc with acetic acid.
Suvomipic (INNTooltip International Nonproprietary Name; developmental code names PP405 and JXL069) is a drug acting as a mitochondrial pyruvate carrier (MPC) inhibitor which is under development for the treatment of alopecia (hair loss), specifically androgenic alopecia (pattern hair loss). It is used topically as a 0.05% concentration gel on the scalp once-daily. Suvomipic is a possible first-in-class drug with a novel mechanism of action in the potential treatment of hair loss. The drug's generic name and chemical structure were published in July 2026, revealing PP405 to be the existing compound JXL069.
The stereoisomer D-phenylalanine (DPA) can be produced by conventional organic synthesis, either as a single enantiomer or as a component of the racemic mixture. It does not participate in protein biosynthesis although it is found in proteins in small amounts—particularly aged proteins and food proteins that have been processed. The biological functions of D-amino acids remain unclear, although D-phenylalanine has pharmacological activity at niacin receptor 2. DL-Phenylalanine (DLPA) is marketed as a nutritional supplement for its purported analgesic and antidepressant activities, which have been supported by clinical trials. DL-Phenylalanine is a mixture of D-phenylalanine and L-phenylalanine. The reputed analgesic activity of DL-phenylalanine may be explained by the possible blockage by D-phenylalanine of enkephalin degradation by the enzyme carboxypeptidase A. Enkephalins act as agonists of the mu and delta opioid receptors, and agonists of these receptors are known to produce antidepressant effects. The mechanism of DL-phenylalanine's supposed antidepressant activity may also be accounted for in part by the precursor role of L-phenylalanine in the synthesis of the neurotransmitters norepinephrine and dopamine, though clinical trials have not found an antidepressant effect from L-phenylalanine alone. Elevated brain levels of norepinephrine and dopamine are thought to have an antidepressant effect. D-Phenylalanine is absorbed from the small intestine and transported to the liver via the portal circulation.
Drying is a mass transfer process consisting of the removal of water or another solvent by evaporation from a solid, semi-solid or liquid. This process is often used as a final production step before selling or packaging products. To be considered "dried", the final product must be solid, in the form of a continuous sheet (e.g., paper), long pieces (e.g., wood), particles (e.g., cereal grains or corn flakes) or powder (e.g., sand, salt, washing powder, milk powder). A source of heat and an agent to remove the vapor produced by the process are often involved. In bioproducts like food, grains, and pharmaceuticals like vaccines, the solvent to be removed is almost invariably water. Desiccation may be synonymous with drying or considered an extreme form of drying. In the most common case, a gas stream, e.g., air, applies the heat by convection and carries away the vapor as humidity. Other possibilities are vacuum drying, where heat is supplied by conduction or radiation (or microwaves), while the vapor thus produced is removed by the vacuum system. Another indirect technique is drum drying (used, for instance, for manufacturing potato flakes), where a heated surface is used to provide the energy, and aspirators draw the vapor outside the room. In contrast, the mechanical extraction of the solvent, e.g., water, by filtration or centrifugation, is not considered "drying" but rather "draining".
Sources: en.wikipedia.org
=== The Healing Foundation === In 1998, as Treasurer of the British Association of Plastic, Reconstructive, and Aesthetic Surgeons (BAPRAS), Brough and his fellow Trustees established The Healing Foundation. Building on the groundwork laid by the Phoenix Appeal, The Healing Foundation aimed to advance research into surgical and psychological healing techniques for individuals with disfiguring conditions. Various UK medical membership bodies provided support to The Healing Foundation as Partner Member Organisations. These partnerships bolstered the charity's credibility, networking capabilities, and financial resources.These organisations were BAPRAS, the British Association of Aesthetic Surgeons, the British Psychological Society, the Craniofacial Society of Great Britain and Ireland, the British Burns Association, and the British Society for Surgery of the Hand.
The All-China Federation of Supply and Marketing Cooperatives (Chinese: 中华全国供销合作总社) is a joint organization of the national supply and marketing Cooperatives of China, led by the State Council, with an administrative level of ministerial level. It is a member of the International Cooperative Alliance (ICA).
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== Structure == PnuC of Salmonella typhimurium and Haemophilus influenzae are integral membrane proteins, 239 and 226 amino acyl residues (aas) in length, respectively, with 7 putative transmembrane α-helical segments. The structure of NadR has been determined. Mutations in the nadR gene which interfere with NR uptake occur in the C-terminal part of NadR. A helix-turn-helix DNA binding domain present in NadR of S. enterica serovar Typhimurium could not be found in the NadR homologue of H. influenzae. Therefore, it was proposed that in H. influenzae NadR has no regulatory function at the transcriptional level. The structures of the human NR kinase 1 (2QL6_P) with nucleotide and nucleoside substrates bound have been solved. It is structurally similar to Rossmann fold metabolite kinases. PnuC has been shown to resemble SWEET porters in overall fold, supporting the conclusion that these two families are members of the TOG superfamily.
unique DNA Also non-repetitive DNA. A class of DNA sequences determined by C0t analysis to be present only once in the analyzed genome, as opposed to repetitive sequences. Most structural genes and their introns are unique.
Sources: en.wikipedia.org
Identity is confirmed by matching the retention time in reversed-phase chromatography against a reference standard and by measuring the molecular mass with mass spectrometry. Tandem mass spectrometry or amino acid analysis can verify the sequence of the seven residues. Because the peptide contains no aromatic amino acids, detection at 280 nm is not useful.
Lyophilized powder is normally stored desiccated at -20 °C, protected from light and moisture. Powder kept under these conditions is generally stable for long periods. Solutions are less stable and are usually prepared immediately before use.
A purity value from one chromatographic method does not capture every possible impurity. Related peptides with similar retention behavior, counterions, and residual solvents may not appear in the same analysis. Independent testing with an orthogonal method provides stronger assurance of identity and content.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, designed as a metabolically stabilized analogue of the endogenous tetrapeptide tuftsin. It has been studied mainly against anxiety-related and cognitive endpoints rather than as an approved medicine in most jurisdictions.