mPEG L-Lysine - MW 20000 Da

Cat. No.: M163997

GRADE & PURITY MW 20000 Da

Storage

Protected from light,Store at -20°C,Argon charged

Shipped In

Ice chest + Ice pads

Vue d’ensemble

Amino acid and peptide PEG conjugates were made from the covalent attachment of PEG to various amino acid derivatives. Conjugates were provided in lyophilized powder form. 

Specifications

Spécifications et pureté

MW 20000 Da

Conditions de stockage de stockage

Protected from light,Store at -20°C,Argon charged

Expédié en

Ice chest + Ice pads

Ce produit nécessite l'expédition en chaîne froide. Les services terrestres et autres services économiques ne sont pas disponibles.

Propriétés chimiques et physiques

• Solubilité: Lyophilized powder form;Soluble in regular aqeous solution and common organic solvents
• Sensibilité: Moisture sensitive；Air sensitive；Light sensitive

Application Protocols

No vendor-validated biological assay protocols are provided for this item. General, literature-based guidance for common uses is below; adapt to your system and verify functionality on small scale first.

• Preparation of stock solution (example): Dissolve mPEG L-Lysine in sterile PBS (pH 7.4) to 10–100 mg/mL. Filter through 0.22 µm if sterility is required. Exact concentration limits depend on Mn and should be determined empirically.
• Protein conjugation via NHS ester (if free amine present on mPEG–Lys partner):
  • Buffer exchange protein into PBS (pH 7.4). Add NHS-activated ligand to a stirred solution of mPEG–Lys and protein at desired molar ratios. React 30–60 min at RT. Quench with Tris or ethanolamine. Purify by SEC or dialysis.
• Surface modification:
  • Activate carboxyl-functional surfaces with EDC/NHS in MES (pH 5.5). Rinse, then incubate with mPEG L-Lysine (1–10 mg/mL) in phosphate buffer (pH 7.4) for 1–2 h. Rinse and cure as needed.
• Nanoparticle stabilization:
  • Mix nanoparticles with mPEG L-Lysine in water or buffer (0.1–5 mg/mL polymer) for 30–60 min; adjust ionic strength to tune adsorption. These are illustrative, literature-style workflows. Optimize stoichiometry and conditions for your exact material and application. For item-specific recommendations, consult the CoA/Spec Sheet.

Biological Roles

No biological activity is claimed for this item. The following is general background (literature/general):

• PEG segment: Poly(ethylene glycol) is widely used to increase hydrodynamic size, reduce nonspecific interactions, and improve solubility of conjugated cargos. It imparts “stealth” behavior by creating a hydrated shell that resists protein adsorption.
• L-lysine segment: Lysine is a basic, essential amino acid. In proteins, ε-amino groups contribute to ionic interactions, enzymatic activity, and post-translational modifications (e.g., acetylation, ubiquitination). In a synthetic conjugate, lysine provides cationic functionality for binding to negatively charged surfaces or biomolecules.
• Conjugate behavior: PEG–amino acid constructs often display reduced immunogenic protein adsorption and improved colloidal stability of nanoparticles. The presence of a free primary amine (if available) can enable electrostatic interactions with nucleic acids and polyanions.
• Enzymatic susceptibility: Amide/carbamate linkages linking PEG to amino acids are generally stable to most physiological enzymes; peptidic spacers beyond lysine can be substrates for proteases. This background is provided to aid experimental design in research contexts (e.g., surface passivation, macromolecular assembly). It does not imply any medical or clinical utility.

Buffer Applications

As a polymeric conjugate rather than a classical buffer, mPEG L-Lysine is not used to set or maintain pH. However, buffer selection is critical for its handling and conjugation (literature/general):

• Coupling to carboxyl groups: Use mildly acidic MES buffer (pH 5.0–6.0) for EDC activation; perform amine coupling in phosphate or HEPES at pH 7.0–7.5 to balance reactivity and hydrolysis.
• Amine-targeted reactions (if free amine present): Carbonate/bicarbonate buffer pH 8.3–9.0 for NHS-ester labeling of dyes/ligands; maintain moderate ionic strength (50–150 mM) to limit aggregation.
• Reductive amination: Sodium phosphate or acetate buffer pH 5.5–6.5 with NaBH3CN; keep organic co-solvent ≤20% (v/v) to solubilize hydrophobic partners.
• Purification: Dialysis or ultrafiltration (MWCO chosen according to PEG Mn) against PBS or water to remove small-molecule reagents.
• Storage buffers: If preparing stock solutions, neutral pH buffers (PBS, HEPES) minimize backbone degradation; include 0.02% sodium azide for bioburden control when appropriate for non-biological assays. Note: Exact functional groups available on this SKU are not specified; tailor buffer choice to the confirmed reactive handle(s).

Green Alternatives

While mPEG L-Lysine is itself often selected for its biocompatibility and aqueous processing, there are broader sustainability considerations (literature/general):

• Solvent choices: Prefer water, buffered aqueous media, or bio-derived alcohols over DMF/NMP. Use DMSO as a higher-boiling, less volatile alternative when water is unsuitable.
• Polymer alternatives and trade-offs:
  • Polyglycerol (PG): Highly hydrophilic, branched, excellent for antifouling; lacks the same historical regulatory familiarity as PEG.
  • Polysarcosine: Non-ionic, peptide-like backbone; excellent stealth behavior; synthesis can be more complex/costly.
  • Poly(2-oxazoline)s: Tunable hydrophilicity; growing body of literature, but fewer long-term data than PEG.

Comparison snapshot (literature/general):

• Criterion | PEG–Lys | Polyglycerol | Polysarcosine
• Renewability | Petro-based ethylene oxide | Can be glycerol-derived (biodiesel byproduct) | Typically petro-based monomers
• Aqueous processing | Excellent | Excellent | Excellent
• Oxidative stability | Good | Good | Good
• Regulatory familiarity | Extensive for PEG | Moderate | Emerging

Greener practices:

• Use minimal organic co-solvent in conjugations; recover and recycle precipitation solvents (acetone/Et2O) where feasible.
• Employ catalytic coupling methods (enzymatic ligation, click chemistries) under aqueous conditions to reduce waste.
• Optimize purification by dialysis/UF instead of repeated chromatographic steps to reduce solvent use.

Pharmaceutical Uses

No therapeutic claims are made. The following information concerns formulation/manufacturing roles (literature/general):

• Excipient/functionality: mPEG–amino acid conjugates are explored as solubilizers, viscosity modifiers, and stealth coatings for nanoparticles and device surfaces. The lysine unit offers cationic interaction sites and a spacing element.
• Conjugation platform: The PEG end-group control and lysine functionality enable attachment of ligands, dyes, or payloads to create defined macromolecular architectures used in preclinical research.
• Processing advantages: High aqueous solubility facilitates sterile filtration and aqueous manufacturing. Low protein adsorption can reduce fouling in process equipment.
• Regulatory context: PEG as an excipient has broad pharmacopeial precedence (e.g., PEG 300–6000 in USP/Ph.Eur.). However, specific PEG–lysine conjugates are not monographed; each material requires its own quality and safety assessment for any GMP use.
• Analytical control: Typical release tests include Mn/PDI (GPC), identity (1H/13C NMR, FTIR), residual solvents, water content, functionality (meq/g), and bioburden/endotoxin where applicable. For this SKU, no GMP status is indicated; treat as research-grade. Verify specifications and suitability for any formulation studies via the lot-specific CoA.

Physical Properties

Item-specific physicochemical data (BP, MP, density, exact solubility): Not specified for this item; refer to CoA/Spec Sheet.

Literature/general characteristics for mPEG–amino acid conjugates:

• Physical state: Typically white to off-white solid or wax, transitioning from waxy to brittle solid as PEG Mn increases; melts to a viscous liquid above its softening point.
• Solubility profile:
  • Water: Good to excellent solubility for most mPEG Mn ranges; lysine increases hydrophilicity (literature).
  • Alcohols (MeOH, EtOH), DMSO, DMF: Usually freely soluble (literature).
  • Nonpolar solvents (toluene, hexanes): Poorly soluble/insoluble (literature).
• Hygroscopicity: PEG segments are mildly hygroscopic; product can absorb moisture and CO2, affecting accurate weighing (literature).
• pKa (lysine primary amines, literature): α-NH3+ ~9.0 and ε-NH3+ ~10.5 in free lysine; conjugation and PEG environment can shift values by ~0.2–1 pH unit.
• LogP: Not applicable in the traditional sense; amphiphilic polymer exhibits high apparent hydrophilicity (literature).
• Refractive index (PEG, literature): nD 20 ~1.46 for liquid PEGs; solids similar when melted. Note: Exact transitions (Tm/Tg), Mn/Mw, PDI, and residual solvent/water content are item-specific and should be taken from the lot CoA.

Quality and Grades

• Grade/Purity for this SKU: Not specified for this item; refer to CoA/Spec Sheet.
• Polymer identity and distribution:
  • mPEG-based materials are defined by an average molecular weight (Mn) and a polydispersity index (PDI). Reported Mn (e.g., 1k, 2k, 5k, 10k) and PDI determine viscosity, solubility, and performance in conjugation. For this item, the exact Mn/PDI are not specified here.
• Typical quality attributes for mPEG–L-lysine products (literature/general):
  • Residual moisture and solvent content controlled; ash and heavy metals typically low for research grade.
  • Functional group content (meq/g) and substitution pattern (α- vs ε-linkage) verified by NMR/FTIR and titration.
  • Endotoxin/bioburden may be monitored for biointerfaces work; unless stated, assume research-grade, not sterile.
• Interpreting grades (general guidance):
  • Research grade: Suitable for synthetic/bioconjugation workflows; not intended for clinical use.
  • High-purity/bioconjugation grade (when specified): Narrow PDI, low UV-absorbing impurities, low residual activators—preferred for sensitive analytics.
• Stabilizers/additives: None indicated for this SKU. If stabilizers are used, they will be listed on the CoA; otherwise assume neat polymer conjugate. Always verify acceptance criteria (Mn, PDI, assay, residuals) on the lot-specific CoA for your application.

Reaction and Applications

Use cases derive from the orthogonal functionality of the lysine residue combined with the solubilizing, stealth properties of mPEG (literature/general):

• Bioconjugation/building block:
  • Free primary amine (if present) enables coupling to activated esters (NHS, PFP), isothiocyanates, squarates, or aldehydes (via reductive amination).
  • Carboxylate handle (if not derivatized) can be activated with EDC/NHS to form amide bonds to amines on proteins, polymers, and surfaces.
• Surface passivation and spacing:
  • Grafting to nanoparticles, hydrogels, and microfluidic channels to reduce fouling; lysine provides multidentate adsorption or crosslinking options.
• Polymer/protein modification:
  • Spacer between bioactive ligands and materials; creates water-soluble conjugates and tunes hydrodynamic radius.
• Self-assembly:
  • Amphiphilic PEG–amino acid motifs can participate in micellization or coacervation with polyanions; useful in drug delivery research and templating.
• Practical tips (literature/general):
  • Maintain anhydrous conditions for organic-phase couplings; use freshly prepared NHS esters.
  • Control pH to 7.5–8.5 for amide formation with NHS esters; too high pH accelerates hydrolysis.
  • Quantify functional group content (meq/g) to calculate stoichiometry; PEG polydispersity necessitates using mmol of functional handles, not just mass. Note: Exact reactive handle(s) present on this SKU are not specified; consult CoA to confirm which groups are free.

Reaction Conditions

General conditions from literature for common transformations involving PEG–lysine conjugates (verify functional handles on this SKU before use):

• NHS-ester coupling to free amine:
  • Solvent: Aqueous phosphate or HEPES buffer (pH 7.4–8.3); for small-molecule labels, 10–20% DMF/DMSO cosolvent.
  • Temperature: 20–25°C.
  • Time: 0.5–2 h.
  • Molar ratios: 1.1–2.0 equiv NHS-ester per amine; monitor by TNBS or ninhydrin assay.
• EDC/NHS coupling via carboxyl group:
  • Solvent: MES buffer pH 5–6 for activation; couple at pH 7–7.5.
  • Reagents: EDC (1.2–3.0 equiv) + NHS (1.2–3.0 equiv) relative to COOH.
  • Temperature: 0–25°C.
  • Time: 0.5–4 h; minimize exposure >pH 8 to reduce hydrolysis.
• Reductive amination (labeling of aldehydes):
  • Solvent: Phosphate or acetate buffer pH 5.5–6.5; optional 10% MeOH.
  • Reductant: NaBH3CN (5–20 mM).
  • Temperature: 20–25°C.
  • Time: 2–16 h.
• Carbamate/urea formation with (iso)cyanates/carbonates:
  • Solvent: Anhydrous DMSO/DMF.
  • Base: DIPEA or TEA (1–2 equiv).
  • Temperature: 0–25°C.
  • Time: 1–6 h.
• Purification: Dialysis/UF (MWCO ~0.5–0.8× PEG Mn) or precipitation from cold acetone/Et2O. Reported yields vary with Mn and reagent excess; polymer conjugation often achieves 60–95% functionalization (literature/general).

Safety and Handling

• GHS/CLP information for this SKU: Not specified for this item; refer to SDS.
• General safety (literature/general):
  • PEG and amino-acid conjugates are generally considered of low acute toxicity; however, handle as a laboratory chemical. Avoid inhalation of dust, ingestion, or contact with eyes/skin.
  • Potential hazards: Dust can cause mechanical irritation. Residual activating esters or coupling byproducts (if present) may be irritants.
• Recommended PPE: Laboratory coat, nitrile gloves, and safety glasses/goggles. Use a dust mask or work in a fume hood when weighing fine powders.
• Handling notes:
  • Work quickly in a low-humidity environment to minimize moisture uptake; cap containers promptly.
  • For moisture/oxygen-sensitive variants, maintain under inert gas as provided (argon-charged per product data).
• Incompatibilities (literature/general): Strong oxidizers; reactive acylating/alkylating agents that may modify free amine or PEG hydroxyls. Avoid strong acids/bases at elevated temperatures to prevent hydrolysis of linkages (amide/carbamate).
• First-aid overview: If inhaled, move to fresh air. In case of skin/eye contact, rinse with water for several minutes; remove contaminated clothing. If ingested, rinse mouth and seek medical attention. Always follow institutional SOPs.
• Spill response: Avoid dust generation. Sweep up and collect for disposal according to local regulations. Authoritative safety information: Consult the product-specific SDS.

Solvent Selection

This product behaves as an amphiphilic, predominantly hydrophilic polymer–amino acid conjugate.

• Polarity/miscibility (literature/general):
  • Water: Typically fully miscible/soluble across common mPEG Mn values; lysine further enhances aqueous compatibility.
  • Polar aprotics (DMSO, DMF, NMP): Excellent solubility, enabling coupling chemistry and film casting.
  • Alcohols (MeOH, EtOH, iPrOH): Generally soluble; solubility decreases with increasing alcohol hydrophobicity and very high Mn.
  • Buffers (PBS, HEPES, carbonate): Good solubility; avoid high ionic strength with very high Mn if salting-out is observed.
  • Nonpolar solvents (toluene, hexanes, MTBE): Poor solubility; use for antisolvent precipitation.
• Practical choices by task (literature/general):
  • Bioconjugation to carboxyls: 50–100 mM MES (pH 5–6) or phosphate (pH 7–7.5) with EDC/NHS; keep organic co-solvent ≤20% to protect biomolecules.
  • Surface modification or polymer–polymer coupling: Anhydrous DMSO/DMF with organic carbodiimides or NHS esters.
  • Purification: Dialysis against water/buffer for aqueous systems; precipitation from cold Et2O/acetone for nonbiological prep.
• Comparison snapshot (literature/general):
  • DMSO vs DMF: DMSO is more benign and higher boiling; DMF may better solubilize some hydrophobic adducts.
  • Water vs buffers: Buffers maintain protonation states of amines; carbonate/bicarbonate (pH 8–9) enhances nucleophilicity of free amines for some coupling chemistries.

Storage and Reconstitution

• Supplied storage guidance (item-specific):
  • Store at −20°C, protected from light, under argon (argon charged). Shipments: Ice chest + ice pads.
• General handling (literature/general):
  • Allow vial to equilibrate to room temperature in a desiccator before opening to prevent condensation. Reseal promptly; backfill with inert gas.
  • Minimize freeze–thaw cycles; aliquot solid or concentrated solutions when feasible.
• Solution stability (literature/general):
  • Aqueous solutions are typically stable for days at 2–8°C; for longer-term storage, freeze at −20°C to −80°C. Avoid repeated freeze–thaw; store in single-use aliquots.
  • Avoid prolonged exposure to strong acids/bases or elevated temperatures to prevent hydrolysis of linkages.
• Reconstitution guidance (general):
  • Solvents: Water, PBS, HEPES buffer, DMSO, or DMF depending on downstream use.
  • Concentration: Prepare working stocks appropriate for your assay (commonly 1–100 mg/mL for polymer conjugates). Determine exact solubility for your Mn empirically.
• Container/materials:
  • Use low-binding polypropylene or glass. For long-term frozen storage, use cryo-compatible, airtight vials with desiccant in secondary containment. Always adhere to the lot-specific CoA/SDS for definitive storage limits and stability information. Research use only, as noted for this product.

Structure and Identity

Brief overview: mPEG L-Lysine typically denotes a conjugate consisting of a monomethoxy poly(ethylene glycol) (mPEG) chain covalently linked to the amino acid L-lysine. The lysine residue can provide one α-amino/α-carboxylate and one ε-amino side chain; depending on the synthesis route, one amine may be PEGylated while the other remains available for downstream coupling (literature/general description).

• Item-specific identifiers
  • CAS: 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.
  • Molecular formula: Not specified for this item; refer to CoA/Spec Sheet. (Note: mPEG conjugates are polydisperse; empirical formula varies with PEG DP.)
  • Molecular weight: Not specified for this item; refer to CoA/Spec Sheet. (PEG-based products are commonly defined by an average Mn.)
• Structural features (literature/general)
  • Polymer segment: Repeating –CH2–CH2–O– units terminated with a methoxy cap (–OCH3).
  • Amino acid segment: L-lysine backbone (–NH2–CH(CH2)4–NH2–COOH) with defined stereochemistry at the α-carbon (S configuration).
  • Functional handles: Depending on protection/derivatization, one free primary amine (ε-NH2) or carboxylate may remain for bioconjugation; exact functionality for this SKU is not specified.
• 2D description (literature/general)
  • A linear polyether chain (mPEG) attached via an amide or carbamate linkage to the α- or ε-position of L-lysine; one terminus capped with methoxy, the other terminus incorporates the lysine residue, potentially bearing a free amine.

Synthetic Utility

mPEG L-Lysine serves as a versatile macromolecular building block (literature/general):

• Functional group chemistry:
  • Primary amine (if present): Nucleophilic substitution on activated carbonyls (NHS esters, acid chlorides), urea/carbamate formation with isocyanates/carbonates, thiourea formation with isothiocyanates, and imine formation followed by reductive amination.
  • Carboxyl group (if present): Carbodiimide-mediated amide coupling to amines on proteins/polymers; formation of active esters for later use.
  • PEG terminus: Methoxy-capped (nonreactive), providing chain solubility and hydrodynamic spacing.
• Retrosynthetic value:
  • Acts as a monofunctional PEG carrier introducing a single lysine node; downstream diversification can occur at the ε-amine or carboxylate, producing star-like or graft copolymers.
• Material synthesis:
  • Grafting-to strategies for surfaces (silica, metals, oxides) via intermediate linkers (e.g., silanes) coupled to lysine amine.
  • Formation of poly(amide) networks by reacting free amines with multiacrylates/epoxides for hydrogel preparation.
• Orthogonality:
  • Protecting-group strategies (Boc/Fmoc on ε-amine) allow stepwise installation of ligands while maintaining PEG solubility. Confirm which reactive site(s) are available on this SKU before planning a route; PEG polydispersity necessitates stoichiometry based on meq of functionality, not mass alone.

Target Specificity

Not applicable. This SKU is a polymer–amino acid conjugate, not an antibody, enzyme, or affinity reagent. No target, epitope, clone, or species reactivity is defined for this product.

Foire aux questions

How should this product be stored?

Store at ?20 °C, protected from light, under argon. It is supplied under an argon blanket; reseal under inert gas after each use.

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.

What documentation is provided?

Available product documentation, including Certificates of Analysis (COA), Safety Data Sheets (SDS), and specification sheets, is shown in the product document area. Document availability and access follow the current site policy.