Pardaxin TFA salt - ≥98% , CAS No.67995-63-5(free base)

CAS: 67995-63-5(free base) Cat. No.: P491924 Formula: C₁₅₆H₂₅₀N₃₆O₄₇(free base) Peso molecolare: 3381.87(free base)

GRADE & PURITY ≥98%

Storage

Store at -20°C,Desiccated

Shipped In

Ice chest + Ice pads

Panoramica

Product Describtion:

Store at -20°C. Store under desiccating conditions. The product can be stored for up to 12 months.

Specifications

Specifiche e purezza

≥98%

Meccanismi biochimici e fisiologici

Antibacterial, apoptotic and neurotoxic ionophore. Forms pores on lipid membranes. Induces caspase-dependent and ROS-mediated apoptosis. Stimulates calcium-independent PLA 2 release of arachidonic acid ( Asc 916 ) and eicosanoids. Active in vivo.

Condizioni di conservazione di stoccaggio

Store at -20°C,Desiccated

Spedito in

Ice chest + Ice pads

Questo prodotto richiede spedizione a catena fredda. I servizi di terra e altri servizi economici non sono disponibili.

Nota

Wherever possible, you should prepare and use solutions on the same day. However, if you need to make up stock solutions in advance, we recommend that you store the solution as aliquots in tightly sealed vials at -20°C. Generally, these will be useable for up to one month. Before use, and prior to opening the vial we recommend that you allow your product to equilibrate to room temperature for at least 1 hour. Need more advice on solubility, usage and handling? Please visit our frequently asked questions (FAQ) page for more details.

Purezza

≥98%

Nomi e identificatori

• Peso molecolare: 3381.87(free base)
• Reaxy-Rn: 32600960
• Reaxys-RN_link_address: https://www.reaxys.com/reaxys/secured/hopinto.do?context=S&query=IDE.XRN=32600960&ln=

Proprietà chimiche e fisiche

• Solubilità: Soluble in water

Application Protocols

No item-specific, validated application protocols are provided for this product. The following examples summarize common literature protocols suitable for pardaxin-type peptides. Optimize and validate in your laboratory.

• Vesicle leakage assay (ANTS/DPX):
  1. Prepare LUVs (e.g., POPC/POPG 7:3) loaded with ANTS/DPX. 2) Dilute vesicles into buffer (e.g., 10 mM HEPES, 150 mM NaCl, pH 7.4). 3) Add peptide from concentrated stock to desired µM levels. 4) Monitor fluorescence increase vs time; normalize to 100% release by detergent.
• Circular dichroism (CD):
  1. Prepare peptide at ~10–50 µM in buffer with/without membrane mimetics (e.g., 20–30 mM SDS, or small % TFE). 2) Record spectra 190–260 nm. 3) Estimate helicity and compare across conditions.
• Antimicrobial susceptibility (broth microdilution; guidance only):
  1. Prepare twofold serial dilutions of peptide in cation-adjusted Mueller–Hinton broth. 2) Inoculate standardized bacterial suspension. 3) Incubate (e.g., 35°C, 16–20 h). 4) Read MIC as lowest concentration with no visible growth. Include solvent and medium controls.
• Hemolysis assay (safety benchmarking in vitro):
  1. Incubate serial peptide dilutions with washed RBCs in isotonic buffer. 2) Quantify hemoglobin release at 540–570 nm. 3) Normalize to Triton X-100 positive control.

Always include appropriate biosafety and waste procedures. These examples are for research use only and are not product-specific validations.

Biological Roles

General/literature context for pardaxin (research-only information; no clinical claims):

• Origin and function: Pardaxin is a defensive peptide originally identified in the secretion of the Red Sea Moses sole (Pardachirus marmoratus). It functions as a cytolytic/antimicrobial factor, contributing to protection against predators and microbes.
• Mechanism (membrane activity): Like many amphipathic peptides, pardaxin interacts preferentially with anionic lipid membranes, adopting an α-helical conformation and promoting membrane permeabilization. Proposed modes include toroidal pore formation or detergent-like carpet mechanisms, with activity modulated by lipid composition (literature reports).
• Spectrum and selectivity (literature): Exhibits broad antimicrobial and hemolytic activity in vitro. Activity and selectivity can vary with ionic strength, presence of divalent cations, and membrane cholesterol content.
• Structure–function insights: Hydrophobic face residues and cationic Lys residues are crucial for activity; helical stability in membrane-mimetic media correlates with potency. Sequence modifications (e.g., charge distribution, hydrophobic moment, terminal capping) are widely studied to tune selectivity.
• Biophysical signatures: Strong negative ellipticity in CD near 208/222 nm in micelles/bilayers; increased helicity with TFE/HFIP; enhanced dye leakage from lipid vesicles; potential for oligomerization at higher surface densities on membranes (literature observations).

Note: The above summarizes well-established literature on pardaxin’s biological roles as a research tool. Consult primary literature for organism-specific or system-specific details relevant to your application.

Buffer Applications

Not typically applicable. Pardaxin is a peptide analyte/standard rather than a buffering agent. It does not serve as a conventional pH buffer system.

Practical note:

• When preparing working solutions, select a buffer that supports your assay (e.g., PBS, HEPES, or low-ionic-strength media). Maintain consistent ionic strength and pH across control and test conditions, and account for any residual acidic counterion (TFA) when adjusting pH after dissolution.

Green Alternatives

Context: As a peptide standard, pardaxin’s environmental profile is dominated by the solvents used for dissolution and assay preparation rather than by the peptide itself. Green chemistry considerations therefore focus on solvent choice and waste minimization.

Greener handling strategies (general guidance):

• Prefer water-rich systems: Maximize the use of buffered aqueous media once initial dissolution is achieved. Use the smallest feasible fraction of organic cosolvent.
• Solvent selection hierarchy: When possible, use water > ethanol/isopropanol (if compatible) > acetonitrile > DMSO > HFIP/TFE (last resort due to toxicity and persistence). Ensure compatibility with your assay and peptide stability.
• Minimize halogenated solvents: Avoid or limit TFE/HFIP and chlorinated solvents. If fluoroalcohols are required for initial dissolution, use minimal volumes and evaporate under controlled conditions with appropriate capture.
• Waste reduction: Prepare concentrated stocks and aliquot to reduce solution waste from repeated freeze–thaw. Scale experiments to match data needs.
• Counterion exchange: If TFA is a concern (acidic effluents), consider exchanging to acetate by repeated dissolution/lyophilization from acetic acid to reduce TFA in aqueous waste (literature practice), if compatible with your protocols.

Comparison (general):

• HFIP/TFE vs aqueous + mild cosolvent: Fluoroalcohols are highly effective for dissolving hydrophobic peptides but have poorer environmental/health profiles; aqueous buffers with small amounts of DMSO/ACN are greener but may require more optimization to avoid aggregation.

Note: Select the greenest conditions that still meet experimental performance and data quality requirements.

Pharmaceutical Uses

No therapeutic or clinical use claims are made for this product. For research use only.

General formulation context (literature/industry perspective for peptides):

• Peptide excipient status: Pardaxin is not used as a pharmaceutical excipient. However, handling principles for peptide actives in preformulation may inform lab practice—e.g., optimizing pH, ionic strength, and cosolvent content to balance solubility and stability.
• Counterion considerations: TFA counterions may be exchanged for acetate or chloride in formulation research to reduce TFA content prior to sensitive biological assays. Such exchanges are typically performed via desalting cartridges or repeated lyophilization from volatile acid solutions (literature practice).
• Analytical controls: For any hypothetical formulation research, monitor purity (HPLC), identity (MS), and aggregation (DLS, SEC) and compare to reference material.

If you require pharmacopeial compliance or cGMP manufacture, this catalog research-grade item is not specified for those uses; consult the CoA/Spec Sheet and contact us to discuss custom manufacturing options.

Physical Properties

Item-specific specifications:

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight (salt form): Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula (salt form): Not specified for this item; refer to CoA/Spec Sheet.
• Other specs (water content, residual solvents, UV cutoff, metals): Not specified for this item; refer to CoA/Spec Sheet.

General/literature properties for pardaxin (free base peptide; for context only):

• Physical form: typically provided as a lyophilized solid or film; hygroscopicity can vary with salt form and residual TFA.
• Solubility: sequence is hydrophobic-amphipathic; dissolution is often improved by initial wetting with small volumes of neat DMSO, 10–50% acetonitrile/water, 0.1% TFA or dilute HCl, followed by dilution with aqueous buffers (literature practice). Final solubility depends on sequence, concentration, and ionic strength.
• Conformation: adopts α-helical structure in membrane-mimetic media (e.g., lipid vesicles, TFE/HFIP, SDS micelles), random coil in pure water (literature observations).
• pI/logP: not meaningful in the classical small-molecule sense; net charge depends on protonation of Lys/N-terminus and the medium. TFA salt increases apparent acidity of solution during dissolution but does not change peptide primary structure.
• Stability: peptides are generally stable lyophilized at ≤−20°C under desiccation; solutions may be less stable, with potential for oxidation (Met, Trp), deamidation (Asn/Gln), or aggregation depending on conditions (literature guidance).

Important: Use the CoA/Spec Sheet for definitive item-specific physical data; the above literature notes are provided for planning and are not product specifications.

Quality and Grades

• Grade/Purity: Not specified for this item; refer to CoA/Spec Sheet.

Interpreting peptide quality (general guidance):

• Peptide purity is commonly expressed as area% by analytical RP-HPLC and confirmed by MS. Typical research grades range from crude (uncommon for bioassays) to ~70–90% and to ≥95% for rigorous biophysical/biological studies. Absent a stated value, review the CoA/Spec Sheet for the exact purity determination method and result for this lot.
• Counterion content: As a TFA salt, pardaxin will bear trifluoroacetate as the counterion to protonated basic sites. Residual TFA can influence solubility, pH upon dissolution, and certain assays (e.g., cell assays). If counterion exchange is needed (e.g., to acetate or HCl), consider standard desalting or lyophilization from volatile acid alternatives.
• Identity testing: Typically established by high-resolution MS (matching expected [M+H]+ for the free base), peptide mapping, and analytical HPLC retention profile. For conformation-sensitive applications, circular dichroism in membrane mimetics can provide comparative fingerprints (literature practice).
• Endotoxin/bioburden: Not specified for this item; if required for sensitive biological assays, request supporting documentation or perform in-house testing.
• Trace contaminants (water, metals, solvents, UV cutoff): Not specified for this item; refer to CoA/Spec Sheet.

Practical tip:

• Upon receipt, verify lot-specific purity and identity against the CoA before initiating critical experiments, especially when comparing activity across lots or versus literature data.

Reaction and Applications

This product is a bioactive peptide standard rather than a classical small-molecule reagent.

Research applications (literature/general):

• Membrane interaction studies: Pardaxin is widely employed as a model amphipathic, lytic peptide to probe peptide–lipid interactions, membrane permeabilization mechanisms, and vesicle leakage kinetics using fluorescence dyes (e.g., calcein, ANTS/DPX) or dye-release assays.
• Structural biophysics: Used in CD, FTIR, solution or solid-state NMR to characterize α-helix formation in membrane-mimetic environments (SDS micelles, DPC, lipid bilayers) and to explore helix–hinge–helix motifs.
• Antimicrobial peptide (AMP) benchmarking: Serves as a positive control in antibacterial/antifungal susceptibility testing and hemolysis assays to compare potency and selectivity of novel AMP analogs (research use only).
• Surface and materials science: Model for studying peptide-induced membrane disruption on supported lipid bilayers (QCM-D, AFM) and in giant unilamellar vesicles (GUVs).
• Sequence–activity relationships: Alanine scanning, terminal truncations, and D/L substitutions of pardaxin analogs are used to dissect contributions of hydrophobic face vs cationic residues to activity and selectivity.

Not typical synthetic reagent uses:

• Pardaxin is not commonly used as a reagent in organic transformations or as a catalyst. For chemical synthesis, pardaxin itself is generally the product of solid-phase peptide synthesis (SPPS) and subsequent purification.

Practical tips:

• Ensure complete dissolution before functional assays. Control for solvent content (e.g., %DMSO or ACN) in activity measurements.

Reaction Conditions

Classical reaction conditions (temperature, catalysts, yields) are not applicable to this peptide product.

Experimental handling conditions (general/literature guidance for biophysical/biological assays):

• Stock preparation: Dissolve at high concentration (e.g., 1–10 mM) in DMSO or ACN/water with 0.05–0.1% TFA or dilute HCl to ensure complete solubilization; then dilute into assay buffer with vigorous mixing. Verify clarity and absence of precipitate.
• Working concentrations: Assay-dependent; literature ranges for membrane leakage or antimicrobial testing are often in the low µM to tens of µM, with matched solvent controls. Determine empirically for your system.
• Temperature: Many assays are performed at ambient temperature (20–25°C) or physiological temperatures (30–37°C). CD or NMR structural studies may vary temperature to probe stability and folding.
• Media/conditions: For membrane studies, use defined lipid compositions (e.g., POPC/POPG mixtures) and controlled ionic strength. For MIC testing, follow standardized media (e.g., cation-adjusted Mueller–Hinton broth) and guidelines.
• Controls: Include solvent-only controls and, where relevant, known lytic peptides as positive controls. Measure peptide concentration by UV (if aromatic residues present) or amino acid analysis for accuracy; TFA content can affect pH and should be considered in controls.

Note: The above are generalized literature practices; optimize for your application and consult primary methods papers.

Safety and Handling

Item-specific hazard data:

• GHS classification: Not specified for this item; refer to SDS.
• Signal word: Not specified for this item; refer to SDS.
• Hazard (H) statements: Not specified for this item; refer to SDS.
• Pictograms: Not specified for this item; refer to SDS.

General laboratory safety guidance for peptides and TFA salts (literature/best practice):

• Handle in a clean, dry environment to minimize moisture uptake. Use appropriate PPE: lab coat, nitrile gloves, and eye protection. Avoid inhalation of powders and aerosols; weigh in a fume hood or glove box if dusting is possible.
• TFA counterion: solutions may be acidic; avoid contact with skin/eyes. Neutralize appropriately before disposal per institutional guidelines.
• Incompatibilities: strong oxidizers can damage susceptible residues; bases can promote deprotonation and, in some cases, enhance aggregation. Avoid prolonged exposure to elevated temperatures, light, and moisture.
• First-aid overview (refer to SDS for authoritative instructions):
  • Inhalation: move to fresh air; seek medical attention if symptoms persist.
  • Skin/eye contact: rinse with water for at least 15 minutes; remove contaminated clothing; seek medical attention if irritation continues.
  • Ingestion: rinse mouth; seek medical advice.
• Spills: avoid dust formation; gently sweep or use HEPA-filtered vacuum. For solutions, absorb with inert material; clean area with appropriate detergents.
• Waste: dispose in accordance with local regulations for organic laboratory chemicals/aqueous peptide solutions.

Note: This product is for research use only. Always consult the product SDS for definitive hazard and handling information.

Solvent Selection

Applicability: Pardaxin is a hydrophobic-amphipathic peptide; solvent strategy focuses on achieving complete initial dissolution and preventing aggregation.

General/literature-guided selection:

• Primary solvents for initial wetting/dissolution:
  • DMSO (anhydrous): excellent first solvent for highly hydrophobic peptides; mix then dilute into aqueous buffer while vortexing/sonication.
  • HFIP or TFE (volatile fluoroalcohols): can disrupt secondary structure and dissolve hydrophobic sequences; often used for stock preparation followed by evaporation and reconstitution in buffer. Handle with appropriate safety.
  • Acetonitrile/water with 0.05–0.1% TFA or formic acid: RP-HPLC-like mixture that can aid dissolution before buffer exchange.
• Aqueous buffers:
  • For working solutions, PBS or low-ionic-strength buffers at pH ~6–7.4 are typical. Small fractions (5–20%) of acetonitrile or isopropanol can maintain solubility. Non-ionic detergents (e.g., 0.05% Tween-20) or mild anionic detergents (e.g., 1–10 mM SDS) are sometimes used in biophysical assays to prevent aggregation (literature practice).
• Membrane-mimetic media: lipid vesicles (SUVs/LUVs), micelles (SDS, DPC), or bicelles are frequently employed to study pardaxin’s helical conformation and membrane interactions.

Selection tips:

• Start with small-volume, high-concentration stock in DMSO or ACN/water, verify clarity (no particulates), then dilute into the assay buffer while mixing.
• Avoid strong base during dissolution (may increase aggregation for hydrophobic peptides). If pH adjustment is required, titrate gently after full dissolution.
• Filter sterilize with low-protein-binding membranes (PVDF, PTFE) if needed; avoid cellulose acetate which can bind hydrophobic peptides.

Storage and Reconstitution

Item-specific storage and shipping:

• Storage conditions: Store at −20°C, desiccated.
• Shipped in: Ice chest + ice pads.

General reconstitution guidance for hydrophobic/amphipathic peptides (literature best practice):

• Equilibrate the vial to room temperature in a desiccator before opening to prevent moisture condensation. Briefly centrifuge to collect material.
• Initial dissolution: Wet with a minimal volume of DMSO, HFIP, or ACN/water with 0.05–0.1% TFA or dilute HCl to achieve full dissolution. Alternatively, add a small volume of water with 0.1% TFA, vortex, and sonicate gently. Once fully dissolved, dilute with the desired buffer while mixing vigorously.
• Working solutions: Prepare fresh when possible. If storage is needed, aliquot into low-protein-binding tubes, flush headspace with inert gas if feasible, and freeze.
• Solution stability (general): Aqueous peptide solutions are typically less stable than the lyophilized solid. For multi-day storage, freeze at ≤−20°C (preferably −80°C) and avoid repeated freeze–thaw by aliquoting. Protect from light and moisture.
• Adsorption/containers: Use low-binding plastics or silanized glass to minimize surface adsorption. Rinse containers with the peptide solution to precondition surfaces when working at low µM concentrations.

Specifications such as exact solubility, concentration limits, and stability for this item are not specified; consult the CoA/Spec Sheet and perform small-scale pilot tests to confirm conditions for your application.

Structure and Identity

• Product: Pardaxin · TFA salt (SKU: P491924)
• CAS: 67995-63-5 (free base; literature)
• Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• InChIKey: Not specified for this item; refer to CoA/Spec Sheet.
• SMILES: Not specified for this item; refer to CoA/Spec Sheet.

General/literature structural information (for pardaxin, free base):

• Pardaxin is an amphipathic, membrane-active peptide originally isolated from the Red Sea sole Pardachirus marmoratus. It is commonly described as a ~33–34 amino-acid, cationic, α-helix-forming peptide with alternating hydrophobic and cationic residues that segregate to opposite faces of the helix (classic antimicrobial peptide topology).
• Representative literature sequence (example): GFFALIPKIISSPLFKTLLSAVGSALSSSGGQE (literature; variants exist). The TFA salt denotes protonated basic sites charge-balanced by trifluoroacetate counterions.
• Key functional features (literature):
  • Multiple hydrophobic residues (Phe, Leu, Val, Ile) drive membrane partitioning.
  • One or more Lys residues confer cationic charge at neutral pH, promoting interaction with anionic lipid headgroups.
  • TFA salt form does not alter the peptide backbone sequence; it affects counterion and protonation state only.

2D/primary-structure description (literature):

• Linear L-peptide, no disulfides, typically adopts an α-helical conformation in membrane-mimetic environments (e.g., SDS micelles, lipid vesicles), with a hydrophobic face (Leu/Val/Ile/Phe-rich) and a polar/cationic face (Lys), consistent with a helical wheel amphipathic layout.

Notes:

• Exact sequence, modifications (if any), and counterion content for this catalog item are not specified here; consult the product CoA/Spec Sheet for definitive identity details.

Synthetic Utility

As a peptide standard, pardaxin is primarily a target of synthesis (via SPPS) rather than a synthetic reagent.

General/literature synthetic context:

• Solid-Phase Peptide Synthesis (SPPS): Pardaxin (∼33–34 aa) is typically assembled on a suitable resin (e.g., Rink amide if C-terminal amide is desired; or Wang for free acid), using Fmoc/tBu strategy. Hydrophobic stretches may require double couplings, extended times, stronger activators (e.g., HATU/HBTU with DIEA), or pseudoproline/isoacyl dipeptide building blocks to reduce aggregation during chain elongation.
• Sequence challenges: High hydrophobicity and propensity for secondary structure formation during synthesis can cause incomplete couplings and deletion sequences. Microwave-assisted SPPS and solvent additives (e.g., DMSO/NMP, HOAt) are often employed.
• Purification: Crude pardaxin is typically purified by preparative RP-HPLC (C18/C8) with water–acetonitrile gradients containing 0.05–0.1% TFA or alternative ion-pairing acids; collected fractions are lyophilized to yield the TFA salt by default.
• Post-synthetic modifications: N-terminal acetylation or C-terminal amidation can tune charge/state; isotope labels (15N/13C) or fluorescent tags (e.g., NBD, FITC) facilitate biophysical studies.

In practical use, pardaxin itself is applied as a research analyte or control peptide in membrane activity studies rather than as a building block or catalyst in small-molecule synthesis.

Target Specificity

Item-specific target, antigen, or clone information: Not applicable/not specified for this product.

General note:

• Pardaxin is a membrane-active peptide without a single defined molecular receptor target; its activity arises from physicochemical interactions with lipid bilayers (literature). Any “specificity” is largely determined by membrane composition (e.g., anionic lipid content, cholesterol level) rather than a discrete protein epitope.

Domande frequenti

What is the purity of this product?

This product is supplied at ≥98% purity (chemical assay). Lot-specific values are stated on the Certificate of Analysis.

How should this product be stored?

Store at ?20 °C, desiccated. Keep the container tightly closed with desiccant — the material is moisture-sensitive.

How is this product shipped?

This product ships in an insulated container with ice pads. Unpack on arrival and transfer it to the storage condition stated above.