Selank 5mg — Vial Spec, Reconstitution Math & COA

Overview of Selank 5mg Vial Specification & Mass Availability

A 5mg vial of Selank contains precisely five milligrams of lyophilized, synthetic heptapeptide (sequence: Thr-Lys-Pro-Arg-Pro-Gly-Pro) formulated as a refined freeze-dried cake. Laboratory researchers select the 5mg mass specification when working within experimental designs that require moderate working volumes, specific serial dilution cascades, or micro-dose analytical assays without subjecting the reconstituted peptide to repeated thermal fluctuations. This standard mass allows research personnel to prepare fresh stock solutions calculated for acute or short-term multi-well plate studies.

While 5mg remains a recognized laboratory standard for benchtop testing, catalog availability at PX1 Research fluctuates based on analytical manufacturing schedules. For ongoing high-throughput trials or larger preclinical rodent cohorts, researchers frequently utilize our primary production format, the Selank 10mg vial, which offers enhanced volumetric flexibility for high-concentration stock preparation. Investigators exploring additional neurological or systemic regulatory compounds can review our complete selection of research peptides to align exact mass specs with active experimental protocols.

Chemical Profile & Molecular Characteristics of Selank

Selank is a synthetic hexapeptide-derived heptapeptide structured as Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was engineered by extending the immunomodulatory peptide tuftsin (Thr-Lys-Pro-Arg) at its C-terminus with a Pro-Gly-Pro tripeptide sequence. This structural modification was introduced in preclinical research settings to significantly increase enzymatic resistance against circulating peptidases, thereby extending the peptide's terminal half-life during in vitro enzymatic degradation assays and animal tissue exposure experiments.

In cell-free and tissue culture models, Selank exhibits stable molecular interactions due to its high purity and defined amino acid sequencing. Preclinical data indicate that the addition of the Pro-Gly-Pro fragment alters the hydrophobic moment of the peptide, improving metabolic stability in plasma assays compared to native tuftsin while preserving binding affinity across targeted central nervous system receptor fractions.

Laboratory Reconstitution Math for 5mg Selank Vials

Reconstitution calculations must be performed accurately to ensure precise concentration delivery across cell cultures or animal models. Reconstituting a 5mg (5,000 micrograms) lyophilized cake of Selank with varying diluent volumes yields the following precise concentration metrics:

1.0 mL Diluent Addition: Yields a final concentration of 5.0 mg/mL (5.0 µg/µL). This high-density stock solution is ideal for micro-volumetric additions where solvent volume must be minimized within cell assay wells. 2.0 mL Diluent Addition: Yields a final concentration of 2.5 mg/mL (2.5 µg/µL). This intermediate concentration provides a balanced volumetric margin, lowering pipetting error rates during routine bench top transfers. 3.0 mL Diluent Addition: Yields a final concentration of 1.67 mg/mL (1.67 µg/µL). Recommended for large-scale microplate allocations requiring higher working diluent volumes to meet minimum pipetting precision limits on automated liquid handlers.

To quickly verify custom stock preparation parameters, laboratory personnel should utilize our automated reconstitution calculator prior to solvent introduction.

Aliquot Planning and Diluent Selection for Preclinical Assays

Selecting the appropriate reconstituting agent depends directly on the scheduled duration and parameters of the research protocol. For immediate single-day assays or enzymatic binding tests, sterile 0.9% Sodium Chloride (Normal Saline) or sterile Water for Injection (WFI) is often suitable. However, for protocols extending past 24–48 hours post-reconstitution, bacteriostatic water (containing 0.9% benzyl alcohol) is strongly recommended to prevent microbial proliferation within the reconstituted vial.

To preserve structural integrity and prevent peptide aggregation, reconstituted stock solutions should be immediately split into single-use sub-aliquots using polypropylene micro-centrifuge tubes. Repeated freeze-thaw cycles subject the peptide backbone to physical shear stresses and ice-crystal formation that induce mechanical degradation. Dividing a 5mg reconstituted stock into 100 µL or 200 µL working aliquots ensures that only the required volume is thawed per experimental run, preserving baseline activity across the entirety of the research study.

Cold-Chain Storage Protocols & Long-Term Stability

Lyophilized Selank 5mg vials must be stored in temperature-monitored environments to maintain chemical stability prior to reconstitution. Unopened vials stored at -20°C remain stable for up to 24 months, while storage at ultra-low freezer temperatures (-80°C) extends shelf life even further. Desiccant packs should be kept within storage containers to prevent moisture ingress, which can cause premature hydrolysis of the lyophilized matrix.

Upon reconstitution, liquid stock solutions must be stored refrigerated between 2°C and 8°C and evaluated within 14 to 28 days depending on the choice of preservative. If long-term storage of reconstituted material is mandatory, working aliquots should be rapidly frozen at -80°C. Avoid standard frost-free freezers for storage, as their automatic temperature cycling causes micro-thawing events that permanently degrade peptide purity.

Lot-Matched COA & Analytical Quality Verification

PX1 Research enforces stringent analytical testing on every production lot of Selank. Every fill size—whether a 5mg or 10mg format—is accompanied by a lot-matched Certificate of Analysis (COA) generated by an independent, ISO 17025 accredited analytical testing facility. Verification relies on High-Performance Liquid Chromatography (HPLC) to confirm peptide purity exceeds 98.0%, combined with Mass Spectrometry (MS) to verify precise molecular weight and sequence identity.

Furthermore, every lot undergoes chromogenic LAL testing to verify that bacterial endotoxin levels remain strictly below pre-established research safety thresholds (<0.05 EU/mg). Principle investigators can independently verify lot numbers and review full chromatographic spectra prior to trial initiation by accessing our dedicated COA lookup portal.

Comparative Analysis: Selank in Relation to Similar Research Compounds

When evaluating synthetic regulatory peptides for preclinical central nervous system or cellular signaling models, researchers often compare Selank against other established peptides within similar functional classes. A comprehensive research program may evaluate Semax alongside Selank to observe comparative neurotrophic factor modulation, as Semax acts primarily via ACTH-derived melanocortinergic pathways. Similarly, investigators exploring tissue protection or systemic homeostasis pathways may incorporate BPC-157 to monitor cytoprotective signaling, while DSIP is frequently examined in distinct central regulatory protocols focusing on circadian or delta-wave modulation. Selecting between these compounds depends on whether the research framework targets GABAergic, neurotrophic, or cellular repair pathways.

Preclinical Research Applications and Receptor Interactions

In vitro and animal model literature documents that Selank interacts with multiple central neurotransmitter and neurotrophic systems. Preclinical studies suggest that Selank modulates the allosteric binding sites of the GABAA receptor complex, enhancing endogenously mediated GABAergic inhibitory currents without altering baseline receptor density. This interaction has made the peptide a focal point in rodent models assessing stress-induced biochemical changes.

Additionally, in vitro gene expression assays indicate that Selank exposure leads to an rapid upregulation of Brain-Derived Neurotrophic Factor (BDNF) and mRNA expression of its primary receptor, TrkB, within hippocampal neuronal cultures. Other animal studies have recorded transient changes in enkephalin stability due to Selank's inhibition of plasma peptidases, providing a rich framework for multi-disciplinary laboratory investigation.

Sourcing Standards and Procurement Options at PX1 Research

All research peptides supplied by PX1 Research are manufactured in state-of-the-art, GMP-compliant facilities located exclusively in the USA. We eliminate supply chain ambiguity by overseeing every step of production, from automated solid-phase peptide synthesis (SPPS) to precise lyophilization and cleanroom vial crimping. Orders ship directly from our centralized distribution facilities in California and Arizona, ensuring rapid, reliable delivery with same-day dispatch for orders confirmed Monday through Friday.

To accommodate various operational scales—from single laboratory projects to multi-center academic trials—PX1 Research provides flexible fulfillment pathways. Academic and corporate institutions needing bulk volume supply or customized packaging for long-term projects can establish dedicated lab accounts via our wholesale procurement service, supported by full access to our comprehensive peptide research library.