PT-141 20mg — Vial Spec, Reconstitution Math & COA

Overview and Physical Specifications of PT-141 20mg Mass

PT-141, chemically designated as Bremelanotide acetate (CAS 189691-06-3), is a synthetic cyclic heptapeptide derivative of alpha-melanocyte-stimulating hormone (α-MSH). In laboratory settings, a 20mg vial spec represents a bulk lyophilized format engineered for high-density assay runs, multi-animal pharmacokinetic studies, or high-throughput cell culture screening. Utilizing a 20mg mass unit minimizes batch-to-batch reconstitution variance across large-scale experimental cohorts.

A standard 20mg lyophilized cake consists of high-purity Bremelanotide lyophile formulated with minimal bulking agents to ensure rapid dissolution upon solvent contact. Research teams evaluating high-volume series often select this mass configuration to maintain consistent stock solutions across multi-week testing protocols. While PX1 Research specializes in standard assay units such as our PT-141 10mg vials, understanding the mathematical and chemical requirements of a 20mg concentration is essential for investigators scaling their experimental designs across our complete line of research peptides.

Melanocortin Receptor Binding Profile and Preclinical Signaling

In preclinical literature, PT-141 acts as a potent, non-selective agonist at central melanocortin receptors, displaying primary binding affinity for the MC3R and MC4R subtypes, with secondary activity at MC1R and MC5R. Unlike peripheral vasoactive compounds, PT-141 exerts its primary effects within the central nervous system, specifically targeting neuronal populations in the hypothalamus, including the paraventricular nucleus (PVN) and medial preoptic area (mPOA).

Preclinical rodent models and in vitro signal transduction assays indicate that activation of central MC4R pathways by PT-141 triggers intracellular cyclic adenosine monophosphate (cAMP) accumulation. This neuroendocrine cascade downstream of melanocortin-receptor signaling has made PT-141 a core subject of investigation in sexual-health research pathways, motivational behaviors, and autonomic central signaling mechanisms. Investigators measuring receptor internalization, cAMP generation, or electrophysiological responses rely on verified peptide mass purity to prevent non-specific receptor crosstalk during preclinical research.

Comparative Analysis: PT-141 vs. Related Melanocortin Agonists

When designing melanocortin pathway protocols, researchers often compare PT-141 against structurally or functionally related synthetic analogues within the same chemical class. The table below outlines key pharmacological distinctions observed across established preclinical literature.

PT-141 differs fundamentally from ancestral compounds like Melanotan II due to its altered C-terminal structure, which significantly dampens peripheral MC1R melanogenesis while preserving central MC4R/MC3R neurogenic activity. Native signaling peptides such as Alpha-MSH exhibit rapid enzymatic degradation by neutral endopeptidases in vitro, whereas the cyclic structure of PT-141 provides enhanced metabolic stability during extended cell-culture incubation. Evaluating these affinity profiles allows research facilities to select the exact melanocortin agonist mass required for targeted assay pathways.

Reconstitution Mathematics for 20mg Peptide Mass

Accurate volumetric reconstitution of a 20mg vial requires precise calculation of peptide concentration per microliter (µL) to ensure exact dosing accuracy in laboratory instruments. Reconstitution should always be performed using bacteriostatic water (0.9% benzyl alcohol) or sterile laboratory-grade physiological saline, depending on cell viability and assay toxicity tolerance.

To calculate working stock concentrations for a 20mg solid mass, apply the standard formula: Concentration = Mass (mg) / Volume (mL). Below are the target concentration matrices for common laboratory diluent volumes:

1.0 mL Diluent Addition: 20mg / 1.0 mL = 20.0 mg/mL (or 20.0 µg/µL). This high-density stock is optimal for ultra-low volume micro-pipetting or minimal-volume microfluidic applications.

2.0 mL Diluent Addition: 20mg / 2.0 mL = 10.0 mg/mL (or 10.0 µg/µL). This standard dilution provides a straightforward 1:10 mass ratio, ideal for routine serial dilutions in microplate binding assays.

3.0 mL Diluent Addition: 20mg / 3.0 mL = 6.67 mg/mL (or 6.67 µg/µL). This moderate concentration minimizes viscosity and facilitates precise volumetric measurement across larger animal model cohorts.

For custom diluent volumes or complex target molarity calculations, researchers should utilize our interactive reconstitution calculator to eliminate manual calculation errors prior to laboratory execution.

Aliquot Planning, Handling, and Storage Protocols

Lyophilized PT-141 mass exhibits robust chemical stability when stored under controlled atmospheric conditions. Upon receipt, un-reconstituted 20mg vials must be preserved at -20°C in a desiccated environment to prevent atmospheric moisture absorption. Under these conditions, the peptide maintains structural integrity and retains analytical purity for up to 24 months.

Once reconstituted, peptide solutions undergo gradual hydrolysis if subjected to repeated thermal fluctuations. Laboratory technicians should institute an immediate aliquotting protocol post-dissolution: divide the stock solution into single-use polypropylene low-binding microcentrifuge tubes and freeze immediately at -80°C. Repeated freeze-thaw cycles must be strictly avoided, as thermal cycling induces peptide aggregation and peptide chain cleavage, compromising assay reproducibility.

Reconstituted working stocks held at standard refrigeration temperatures (2°C to 8°C) should be utilized within 14 days. Avoid vortexing or aggressive mechanical agitation during dissolution; gentle end-over-end inversion ensures complete solvation without introducing shear stress to the cyclic peptide ring.

Analytical Quality Validation: COA, HPLC, MS, and Endotoxin Standards

Every batch of PT-141 supplied by PX1 Research undergoes stringent analytical verification in ISO 17025 accredited testing laboratories. Quality assurance is documented via a lot-specific Certificate of Analysis (COA), accessible directly by lot number for complete supply chain transparency.

Purity assessment is performed via High-Performance Liquid Chromatography (HPLC) coupled with UV detection at 220 nm. PX1 Research mandates a minimum purity threshold of ≥99.0% area-under-curve (AUC) for all distributed lots. Mass identity is independently confirmed using Electrospray Ionization Mass Spectrometry (ESI-MS), verifying the monoisotopic mass of Bremelanotide at 1024.2 g/mol without residual synthesis reagents or unexpected truncation fragments.

Because melanocortin receptor assays are highly sensitive to immune activation, biological safety screening is paramount. Every lot is subjected to Limulus Amebocyte Lysate (LAL) kinetic chromogenic assays to confirm endotoxin levels strictly below <0.5 EU/mg. This rigorous testing guarantees that observed cellular responses are driven exclusively by specific melanocortin agonist signaling rather than bacterial lipopolysaccharide contamination.

Container Closure Integrity and Packaging Architecture

The physical architecture of the vial container closure system is vital for preventing degradation of dry peptide lyophiles during storage and transit. PT-141 20mg specs are filled into USP Type I borosilicate glass vials, chosen for superior chemical inertness and resistance to hydrolytic leaching compared to standard soda-lime glass.

Vials are sealed using chlorobutyl rubber stoppers coated with a fluoropolymer film, forming an impermeable barrier against atmospheric oxygen, moisture infiltration, and volatile organic compounds. The assembly is secured with an aluminum flip-off crimp seal to maintain vacuum integrity. This packaging design guarantees that the internal nitrogen headspace remains inert, preserving the peptide cake until the rubber septum is punctured during laboratory reconstitution.

Selecting Vial Format: 20mg Mass vs. 10mg Standard Sizes

Choosing between a 20mg vial and smaller configurations like the standard PT-141 10mg format depends entirely on the operational scale and timeline of the research protocol. High-throughput screening platforms, automated liquid handling systems, and large animal cohort studies benefit from 20mg vials due to reduced reconstitution steps, streamlined storage footprints, and operational cost efficiency.

Conversely, specialized pilot studies, low-frequency exploratory assays, or protocols requiring low working volumes may prefer 10mg vials. Utilizing smaller mass units reduces the duration a reconstituted solution remains in liquid state, thereby minimizing the risk of inadvertent contamination or concentration drift over time. Laboratories setting up recurring ordering schedules across diverse research units can contact our dedicated wholesale department to configure custom vial allocations matched to exact trial timelines.

PX1 Research Supply Chain Integrity and Manufacturing Standards

PX1 Research operates as a premier USA-based supplier of high-purity research compounds. All peptides are manufactured under strict Good Manufacturing Practice (GMP) compliant guidelines, ensuring absolute batch-to-batch consistency and rigorous quality control at every phase of synthesis and freeze-drying.

Orders are dispatched directly from our dual distribution centers located in California and Arizona. Orders placed Monday through Friday before cut-off times qualify for same-day shipping, ensuring rapid delivery to minimize environmental temperature exposure during transit. Laboratories utilizing PX1 Research compounds receive unmatched transparency, verified analytical documentation, and dedicated technical support tailored to advanced analytical and preclinical research demands.