SS-31 20mg — Vial Spec, Reconstitution Math & COA

Product Overview and Technical Specification of the SS-31 20mg Format

The 20mg vial of SS-31 (also known in scientific literature as Elamipretide or MTP-131) contains a highly purified, lyophilized powder engineered for laboratory research use only. Chemically structured as a synthetic tetrapeptide with the sequence D-Arg-Dmt-Lys-Phe-NH2, SS-31 possesses a unique molecular weight of 839.98 g/mol. The 20mg mass configuration is specifically designed for investigative laboratories requiring larger working stocks to perform high-throughput screening or repeated micro-dosing protocols across extensive experimental cohorts without frequent lot switching.

In preclinical settings, researchers choose the 20mg vial size when executing multi-week animal studies or high-density cellular bioenergetic assays. Utilizing a larger single-vial mass minimizes inter-vial variance across an entire study arm. To inspect current availability, structural data, and alternate mass options, investigators can explore the primary SS-31 product page or review the complete catalog of synthetic compounds within the PX1 peptide library. Should a specific study protocol call for smaller baseline testing volumes, 10mg configurations are also maintained under identical manufacturing controls.

Physicochemical Properties and Molecular Profile

SS-31 belongs to the aromatic-cationic class of mitochondria-targeted peptides. Its primary sequence incorporates alternate aromatic residues and basic amino acids, enabling it to penetrate cellular membranes independently of membrane potential. Unlike conventional lipophilic cations, SS-31 selectively concentrates at the inner mitochondrial membrane (IMM) by binding electrostatically and hydrophobically to cardiolipin—a unique tetraacyl phospholipid essential for mitochondrial cristae structure and electron transport chain complex assembly.

Because of its basic lysyl and arginyl side chains, lyophilized SS-31 exhibits high water solubility and forms a clear, colorless solution upon contact with aqueous reagents. The peptide is supplied as a trifluoroacetate (TFA) or acetate salt, stabilized under inert argon atmosphere inside USP Type I borosilicate glass vials with rubber butyl stoppers and flip-off aluminum seals. This packaging preserves structural integrity against moisture uptake and oxidation during low-temperature storage.

Reconstitution Calculations for 20mg SS-31 Vials

Accurate concentration calculations are vital when reconstituting a 20mg mass unit to ensure precise working aliquots for downstream assay setups. Reconstitution protocols typically employ Bacteriostatic Water for Injection (0.9% benzyl alcohol), sterile 0.9% Sodium Chloride (saline), or laboratory-grade Phosphate-Buffered Saline (PBS, pH 7.4), depending on whether the application involves in vitro cell culture or in vivo animal models.

Below are the specific concentration outcomes based on the total diluent volume added to a standard 20mg SS-31 lyophilized vial:

• 1.0 mL Diluent Volume: Yields a final concentration of 20.0 mg/mL (20.0 µg/µL). This high concentration is ideal for low-volume micro-injections or preparing concentrated stock solutions intended for subsequent serial dilution in culture media.

• 2.0 mL Diluent Volume: Yields a final concentration of 10.0 mg/mL (10.0 µg/µL). A 10 mg/mL concentration simplifies volumetric measurements during assay preparation, where 10 µL of stock provides exactly 100 µg of active compound.

• 3.0 mL Diluent Volume: Yields a final concentration of 6.67 mg/mL (6.67 µg/µL). This diluted matrix is advantageous when working with pipette systems that require larger fluid volumes to maintain volumetric accuracy, or when administering systemic treatments in rodent models.

To quickly recalculate final molarity or mass concentrations based on custom solvent volumes, researchers are encouraged to utilize the interactive PX1 Reconstitution Calculator.

Aliquot Planning and Storage Stability Protocols

Lyophilized SS-31 demonstrates robust stability when stored at -20°C to -80°C in a desiccated environment, remaining stable for up to 24 months from the date of synthesis. However, once reconstituted into an aqueous phase, peptides become susceptible to hydrolytic degradation, peptide cleavage, and surface adsorption if not handled under strict thermal management protocols.

To maximize the shelf life of reconstituted SS-31 20mg stocks, research staff should avoid repeated freeze-thaw cycles, which induce physical shear stress and localized concentration gradients that promote peptide aggregation. Following initial reconstitution, the solution should be immediately divided into single-use, low-binding polypropylene micro-aliquots (e.g., 50 µL to 200 µL) inside a sterile laminar flow hood. Working aliquots stored at 4°C should be used within 3 to 7 days, whereas master aliquots frozen at -80°C maintain structural stability for 3 to 6 months.

Lot-Matched COA Verification and Quality Assurance

Every batch of SS-31 manufactured for PX1 Research undergoes rigorous analytical testing in ISO 17025 accredited, third-party laboratories within the United States. Quality assurance protocols confirm compound identity, purity, and safety profiles prior to lot release. Each 20mg vial shipped to a facility is accompanied by or linked to a lot-matched Certificate of Analysis (COA).

Key analytical metrics evaluated on the SS-31 COA include:

1. High-Performance Liquid Chromatography (HPLC): Confirms chemical purity. PX1 mandates a minimum HPLC purity threshold of ≥98.0%, ensuring that micro-impurities and truncated sequences are minimized.

2. Mass Spectrometry (MS): Verifies exact molecular mass (839.98 g/mol observed [M+H]+) against theoretical values to guarantee sequence fidelity.

3. Endotoxin Quantitation: Measured via Chromogenic Reagent (LAL) testing to ensure endotoxin levels remain below 0.01 EU/mg, preventing confounding inflammatory responses in sensitive cell lines or animal assays.

Researchers seeking to review batch-specific analytical records or verify test documentation for their facility's compliance records can access the dedicated COA verification portal.

Comparative Analysis: SS-31 vs. Related Mitochondrial Peptides

Within mitochondrial bioenergetics research, SS-31 is frequently evaluated alongside other mitochondria-derived or targeted peptides. Understanding the distinct mechanisms and chemical structures of these compounds helps investigators select the proper tool for their experimental models.

While SS-31 specifically targets cardiolipin on the inner mitochondrial membrane to optimize electron transport chain kinetics and reduce electron leakage, MOTS-c is a mitochondria-encoded peptide that acts primarily as a metabolic regulator via the AMPK pathway, influencing nuclear gene expression and systemic insulin sensitivity. Similarly, Humanin serves as a cytoprotective factor that suppresses apoptosis by binding BAX and interacting with cell-surface receptors. While MOTS-c and Humanin act via signaling cascades, SS-31 operates through direct physical interaction with IMM lipids, making it uniquely suited for assays focused on membrane biophysics, ATP synthase efficiency, and localized reactive oxygen species (ROS) attenuation.

Selecting the Optimal Format: 10mg vs. 20mg Vials

Choosing between a 10mg and a 20mg vial configuration depends on study design, assay scale, and total compound throughput. The 20mg vial format offers significant operational advantages for high-volume research applications, reducing procurement overhead and ensuring that large experimental groups receive compound from a single uniform batch.

Conversely, smaller pilot studies or exploratory in vitro screens may benefit from 10mg vials to minimize the prolonged storage of reconstituted liquids. If your laboratory anticipates high-frequency usage or requires bulk procurement for long-term research programs, custom sizing and institutional pricing options can be coordinated through PX1 Wholesale Services.

Preclinical Mechanisms and In Vitro Application Focus

Preclinical studies indicate that SS-31 exerts its primary biophysical action by inserting its hydrophobic dimethyltyrosine and phenylalanine residues into the hydrophobic core of cardiolipin, while its basic arginine and lysine residues form ionic bonds with cardiolipin's phosphate headgroups. This spatial orientation stabilizes cardiolipin microdomains, preventing its oxidation by cytochrome c.

In vitro data demonstrate that under conditions of oxidative stress or ischemia-reperfusion models, SS-31 administration preserves mitochondrial cristae architecture, prevents the opening of the mitochondrial permeability transition pore (mPTP), and maintains coupling efficiency in oxidative phosphorylation. Rodent models of cardiotoxicity and neurodegeneration further show that targeted IMM protection reduces lipid peroxidation markers (such as malondialdehyde) and supports cellular ATP recovery without altering baseline mitochondrial respiration in healthy control tissues.

Laboratory Handling, Safety Parameters, and Compliance

All SS-31 20mg vials distributed by PX1 Research are strictly intended for laboratory research use only by qualified scientific personnel. These compounds are not for human or veterinary use, medical diagnosis, therapeutic treatment, or clinical administration. Safe handling protocols dictate that research personnel wear appropriate Personal Protective Equipment (PPE), including nitrile gloves, lab coats, and safety eyewear, when opening, reconstituting, and transferring liquid peptide formulations.

Reconstitution should take place within a certified biosafety cabinet or clean bench environment to preserve solution sterility. Spills should be neutralized with standard laboratory disinfectant and wiped down according to institutional hazardous material guidelines. All waste materials, including micro-tubes, pipette tips, and empty vials, must be disposed of in accordance with local regulations governing bio-research reagents.