8 Arm PEG Biotin - MW 10000 Da

Cat. No.: A163131

GRADE & PURITY MW 10000 Da

Storage

Store at -20°C,Argon charged

Shipped In

Ice chest + Ice pads

Descripción general

8 arm PEG biotin derivatives have 8 biotins one each PEG molecule that can be used to modify proteins, peptides and other materials via their functional groups. PEGylation can increase solubility and stability and reduce immunogenicity of peptides and proteins. It can also suppress the non-specific binding of charged molecules to the modified surfaces. .

Specifications

Especificaciones y pureza

MW 10000 Da

Condiciones de almacenamiento de almacenamiento

Store at -20°C,Argon charged

Enviado en

Ice chest + Ice pads

Este producto requiere envío en cadena de frío. Los servicios terrestres y otros servicios económicos no están disponibles.

Propiedades químicas y físicas

• Solubilidad: Off-white/white solid or viscous liquid depends on molecule weight;Soluble in regular aqeous solution as well as most organic solvents
• Sensibilidad: Moisture sensitive

Application Protocols

Item-specific, tested application protocols (WB, IHC, IF, FC, etc.)

• Not specified for this item; refer to CoA/Spec Sheet or SDS for any available handling notes.

Where to find practical guidance

• See the Reaction & Applications and Reaction Conditions sections for general, literature-based setup considerations applicable to 8-arm PEG–biotin reagents.

Biological Roles

General information (literature/general; not specific to this item)

• Biotin (vitamin B7/H) is a cofactor for carboxylase enzymes involved in fatty acid synthesis, gluconeogenesis, and amino acid catabolism. In bioconjugation, the biotin moiety is leveraged primarily for its exceptionally high-affinity interaction with avidin/streptavidin (Kd ~10^−14–10^−15 M), enabling selective capture and assembly.
• PEGylation imparts hydrophilicity, reduces nonspecific protein adsorption, and can mitigate aggregation. Multiarm PEGs provide multivalency, allowing denser display of terminal groups per molecule.
• In research tools, 8-arm PEG–biotin serves as a multivalent scaffold to organize biomolecules via biotin–(strept)avidin bridges, create antifouling surfaces, and modulate spatial presentation of ligands.

Caveats

• Biological function of this macromer in living systems is not a therapeutic role; it is a laboratory reagent for affinity-driven assembly. Performance can be influenced by buffer composition, temperature, and presence of competing biotin.

Item-specific note

• No additional biological characterization is provided for this item; for endotoxin/bioburden or protein-binding capacity, refer to the CoA/Spec Sheet if available.

Buffer Applications

Relevance

• 8 Arm PEG Biotin is not itself a buffering agent. It is typically used in buffers to assemble or immobilize components via the biotin–(strept)avidin interaction.

Practical guidance (literature/general)

• Common buffers: PBS (10–50 mM phosphate, 150 mM NaCl, pH 7.2–7.4), HEPES (10–25 mM, pH 7.2–7.5). Maintain neutral pH to preserve protein activity and biotin integrity.
• Additives: 0.01–0.1% Tween-20 can reduce nonspecific adsorption to plastics; BSA (0.1–1%) can serve as a blocking agent when working with surfaces.
• Avoid: Excess free biotin or biotin-containing supplements in working buffers—they competitively inhibit binding.
• Filtration: Sterile-filter buffers (0.22 µm) for cell-contacting workflows.

Item-specific buffer recommendations

• Not specified for this item; refer to CoA/Spec Sheet. Use the Reaction & Applications and Reaction Conditions sections for general setup considerations.

Green Alternatives

Perspective (literature/general)

• Polymer choice: PEG is widely used due to aqueous solubility and biocompatibility. Alternatives include dextran- or polysaccharide-based biotinylated polymers that are bio-based and potentially more renewable.
• Solvent choice: Prefer water or buffered saline over aprotic polar solvents when feasible. If organic solvent is necessary, ethanol is a greener option relative to DMF/DMSO for some workflows.

Comparison (general, non-item-specific)

• PEG–biotin vs. dextran–biotin: Dextran is renewable and biodegradable; however, it can be more polydisperse and less defined in architecture than synthetic multiarm PEGs, affecting reproducibility.
• PEG–biotin vs. PVA–biotin: Poly(vinyl alcohol) is water-soluble and can be sourced with lower toxicity profiles, but functionalization chemistry and protein resistance may be less favorable than PEG.
• Binding strategy: Biotin–(strept)avidin is robust but uses a tetrameric protein; greener alternatives may use metal-free click chemistry (e.g., SPAAC) with azide–DBCO polymers to avoid protein components—tradeoff is lower on/off kinetics versatility and different selectivity.

Operational greening

• Employ aqueous buffers, ambient temperature assembly, and minimal excess reagent to reduce waste.
• Reuse streptavidin-functionalized substrates when permissible by the application to limit consumable usage.
• This item’s specific environmental credentials (renewable content, residual solvent levels) are not specified; consult the CoA if needed.

Pharmaceutical Uses

Scope

• This product is designated for research use only (per Product Data) and is not intended for human or veterinary use.

General formulation/processing context (literature/general)

• PEG–biotin macromers are employed in research-scale manufacturing of affinity purification tools (e.g., creating biotinylated PEG layers on chromatography media) and in diagnostic assay components where multivalent biotin is advantageous.
• In regulated settings, analogous materials may be available as GMP-grade with defined endotoxin/bioburden and full traceability; grade for this item is not specified.
• As an excipient concept, PEG architectures can modulate viscosity and surface properties, but biotin end-groups are typically reserved for affinity capture rather than excipient functionality.

Compliance notes

• No pharmacopeial monograph applicability is provided for this item. For any process development work that could translate toward clinical manufacturing, source appropriate GMP-grade equivalents and perform full quality/regulatory assessments.

Physical Properties

Item-specific specifications

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight (Mn/Mw), polydispersity, substitution: Not specified for this item; refer to CoA/Spec Sheet.

Literature/general expectations for 8-arm PEG–biotin (non-item-specific)

• Physical state: Typically solid (powder or fluffy solid) at ambient temperature for Mn in the 5–80 kDa range (literature).
• Solubility: Highly soluble in water and many polar organics (e.g., methanol, ethanol, DMSO); limited solubility in nonpolar solvents (literature). Biotin end-groups do not significantly reduce aqueous solubility of PEG.
• Density, refractive index, logP: Not typically reported for macromers; highly dependent on molecular weight and hydration (literature).
• pKa: Not applicable—PEG backbone is neutral; biotin is largely neutral at physiological pH (literature).
• Glass transition (Tg): PEG Tg around −60 to −50 °C; melting transitions depend on crystallinity and molecular weight; multiarm PEGs are often amorphous (literature).
• Viscosity: Aqueous solutions can become highly viscous at concentrations >10–20 wt% depending on Mn (literature).

Note: Exact numerical values (Mn, arm length n, linker identity) are not specified for this item; consult the CoA/Spec Sheet for definitive property data.

Quality and Grades

Item-specific quality information

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

How to evaluate quality for 8-arm PEG–biotin (general guidance)

• Substitution level (functionalization): Verify that all eight arms are biotin-terminated (degree of substitution, DS). Common assays include HABA/Avidin displacement and NMR end-group analysis.
• Molecular weight and dispersity: Size-exclusion chromatography (SEC/GPC) with multi-angle light scattering (MALS) provides Mn/Mw and Đ. Narrow dispersity indicates well-controlled synthesis.
• Residuals/impurities: Check for residual solvents, salts, or unreacted biotin/linker by NMR, LC–MS (for fragments), and Karl Fischer for water (if relevant). Item-specific limits are not provided here.
• Biotin accessibility: For surface and biological applications, verify avidin-binding capacity in solution and on surfaces (biotin may be sterically hindered depending on linker length).
• Endotoxin/bioburden: For cell-contact studies, vendors may offer low-endotoxin grades; status for this item is not specified—consult documentation if this is critical.

Implications of stabilizers/additives

• No stabilizers are listed for this item. If stabilizers were used (e.g., antioxidants), they should be disclosed on the CoA; none are specified here.

Reaction and Applications

Applications (literature/general)

• Affinity assembly: Multivalent biotin enables strong, specific binding to avidin, streptavidin, or neutravidin, facilitating rapid, noncovalent crosslinking and surface capture.
• Hydrogel formation: Combining 8-arm PEG–biotin with streptavidin can yield physically crosslinked, reversible hydrogels useful for immobilization and 3D culture research (non-clinical).
• Surface functionalization: Coating of beads, sensors, or microplates pre-functionalized with (strept)avidin to present a dense PEG layer that resists nonspecific adsorption while offering biotin handles.
• Multivalent display: Presentation of multiple ligands co-attached via secondary biotin–avidin bridges (e.g., biotinylated peptides or oligos bound to a streptavidin node interacting with PEG–biotin).
• Spacer functionality: PEG arms act as hydrophilic, flexible spacers improving solubility and reducing aggregation of attached biomolecules.

Practical tips

• Maintain neutral pH (≈7.0–7.5) and physiological ionic strength for optimal avidin-family binding.
• Control stoichiometry: One streptavidin tetramer binds up to four biotins; with 8-arm PEG–biotin, network formation depends on mixing ratios and concentration—optimize empirically.
• Avoid free biotin in formulations; it competes for binding sites and can inhibit assembly.
• For surface work, block nonspecific sites (e.g., with BSA or PEG) before introducing PEG–biotin to minimize background.

Note: No manufacturer application specifics were provided for this item; the above are literature/general use cases for this class of macromers.

Reaction Conditions

General assembly conditions for biotin–(strept)avidin systems (literature/general)

• Solvent/buffer: PBS or HEPES, pH 7.2–7.5. Avoid amine-reactive buffers if conjugating proteins elsewhere. Minimize free biotin.
• Temperature: Ambient (20–25 °C) is typical; 4 °C can be used to reduce nonspecific interactions.
• Stoichiometry: One streptavidin tetramer binds up to four biotins. For network formation with 8-arm PEG–biotin, adjust the molar ratio to tune crosslink density; begin with near-stoichiometric equivalents of biotin-binding sites.
• Concentrations: Working concentrations often range from 0.01–10 mg/mL depending on molecular weight and application (e.g., coating vs. gelation). Optimize empirically.
• Time: Binding is rapid (minutes) but equilibrations of macroscopic structures (e.g., gels, coatings) may require 0.5–2 h.
• Additives: Include blocking agents (e.g., BSA) to reduce nonspecific binding on surfaces; add detergents (0.01–0.1% Tween-20) judiciously to limit hydrophobic sticking.

Notes and caveats

• Salt and pH outside physiological ranges can impact avidin-family stability. Maintain gentle conditions to preserve function.
• If making films/coatings, rinse unbound polymer with buffer after incubation to reduce background.

Item-specific parameters (concentration windows, exact MW) are not specified; consult CoA/Spec Sheet and perform small-scale optimization.

Safety and Handling

Item-specific hazard details

• GHS classification, signal word, pictograms, H-statements: Not specified for this item; refer to SDS.

General safety guidance (literature/general)

• PEG-based bioconjugates are generally regarded as low hazard for laboratory handling; however, always defer to the product SDS.
• Recommended PPE: Laboratory coat, safety glasses, and appropriate chemical-resistant gloves. Avoid inhalation of dust/aerosols; handle powders in a fume hood or ventilated enclosure.
• Incompatibilities: Strong oxidizers may degrade PEG backbones; avoid reactive acylating/alkylating agents unless intentionally conjugating. Thermal decomposition may release irritating fumes.
• Hygroscopicity: PEGs can be hygroscopic; keep containers tightly closed and minimize exposure to ambient moisture.
• First aid overview: If inhaled—move to fresh air. Skin/eye contact—rinse with water for at least 15 minutes; remove contaminated clothing. If ingested—rinse mouth; seek medical attention as needed. Always follow SDS instructions.
• Environmental: Prevent uncontrolled release to drains; collect spills with inert absorbent. PEGs are water soluble; contain and dispose per institutional and local regulations.

Special risks and handling tips

• Biotin end-groups are stable under neutral aqueous conditions; avoid prolonged exposure to strong acids/bases or high temperatures that can hydrolyze linkers (general).
• Use clean, low-binding plastics or glassware to minimize adsorption losses in dilute solutions.

Solvent Selection

General solvent behavior (literature/general)

• Polarity: PEG is highly polar and hydrogen-bond accepting; star-PEGs remain water-miscible across common molecular weights.
• Aqueous media: Freely soluble in water, PBS, Tris, and HEPES at neutral pH. Salt can modestly affect hydration but typically does not precipitate PEG at moderate ionic strengths.
• Organic media: Soluble in methanol, ethanol, isopropanol, acetonitrile, DMF, DMSO; limited in acetone at high Mn and typically insoluble in hydrocarbons and chlorinated nonpolar solvents.
• Mixed media: DMSO or DMF stock solutions (e.g., 10–100 mg/mL) can be diluted into water or buffers.

Selection tips

• Choose water or PBS (pH ~7.2–7.4) for biotin–(strept)avidin applications to maintain protein activity.
• Use DMSO (anhydrous) to prepare concentrated stocks when rapid dissolution is needed; dilute into buffer immediately before use.
• For surface modification, use buffer systems compatible with the substrate (e.g., carbonate buffer for adsorption to some plastics) while maintaining biotin integrity.

Practical notes

• Warm gently (room temperature to 37 °C) and vortex to aid dissolution; avoid overheating.
• Filter sterilization (0.22 µm) is generally feasible; viscosity may require lower concentrations to pass filters.
• Exact solvent constraints for this item are not specified; confirm compatibility with your assay components.

Storage and Reconstitution

Item-specific instructions (from Product Data)

• Storage: Store at −20 °C, Argon charged.
• Shipping: Ice chest + ice pads.
• Research use only.

General guidance (literature/general; adapt to your workflow)

• Protect from moisture: PEGs can be hygroscopic; keep container tightly sealed under inert gas as indicated.
• Light/temperature: Room-temperature handling during weighing and dissolution is acceptable; return to −20 °C promptly after use.
• Reconstitution: Dissolve the required amount in high-purity water, PBS, or compatible buffer to desired concentration. For difficult dissolution, use a minimal volume of DMSO to prepare a concentrate, then dilute into buffer.
• Filtration: If sterility is required, filter through a 0.22 µm membrane. Viscosity may necessitate moderate concentrations.
• Aliquoting: Prepare single-use aliquots to avoid repeated freeze–thaw and headspace moisture ingress; re-purge headspace with inert gas before re-freezing.

Stability notes

• Avoid prolonged exposure to strong acids/bases or oxidizers that can degrade PEG or linkers. Do not store in the presence of free biotin if subsequent avidin-binding applications are planned.

Any exact shelf-life or stability specifications are not provided for this item; consult the CoA/Spec Sheet for definitive guidance.

Structure and Identity

Item-specific facts (from Product Data)

• Product name: 8 Arm PEG Biotin (SKU: A163131)
• CAS: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular formula: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular weight: Not specified for this item; refer to CoA/Spec Sheet.
• SMILES / InChI / InChIKey: Not specified for this item; refer to CoA/Spec Sheet.

General structural description (literature/general)

• Architecture: Star-shaped, poly(ethylene glycol) (PEG) scaffold with a central core branching into eight discrete PEG arms.
• Termini: Each arm is terminated with a biotin moiety, enabling multivalent, high-affinity binding to avidin/streptavidin family proteins.
• Functional groups: Repeating ether linkages along PEG chains; terminal ureido-tetrahydrothiophene ring system characteristic of biotin at each chain end (exact linker chemistry varies by supplier; not specified for this item).
• Topology: 0D star polymer; hydrophilic PEG domains confer water solubility; biotin end-groups provide specific affinity interactions without introducing charge at neutral pH.
• 2D verbal depiction: A central hub connects eight flexible –(CH2CH2O)n– chains, each ending with a biotin cap; overall neutral, amphiphilic macromolecule with narrow to moderate dispersity depending on synthesis (not specified for this item).

Synthetic Utility

Conceptual utility (literature/general)

• Macromolecular scaffold: The 8-arm star configuration provides eight terminal biotin groups for orthogonal, noncovalent assembly with avidin-family proteins, enabling hierarchical construction of larger architectures.
• Spacer function: Each PEG arm offers a flexible, hydrophilic spacer that can improve target accessibility of biotin and reduce steric hindrance for attached biomolecules.
• Antifouling coating: Dense PEG presentation reduces nonspecific adsorption on surfaces while maintaining specific capture through biotin ends.
• Modular assembly: Combine with streptavidin and secondary biotinylated ligands (peptides, oligos, fluorophores) to build multi-component complexes without covalent chemistry.

Retrosynthetic/design considerations

• If further functionalization is needed, variants bearing additional orthogonal handles (e.g., azide, alkyne, maleimide) on the core or along arms can be chosen; this item’s additional handles (if any) are not specified.
• Control of valency and spacing can be tuned via PEG arm molecular weight (n repeat units per arm). Exact arm length for this item is not specified.

Limitations

• Noncovalent assemblies can dissociate under harsh conditions (e.g., exposure to free biotin, extreme pH, denaturants). For permanent linkages, consider covalent click or enzyme-mediated ligations.

Target Specificity

Not applicable to this product type.

• This listing is not an antibody or affinity protein. No antigen/epitope/clone/isotype data are provided in the Product Data, and none are assigned here.
• Note (literature/general): Biotin binds with high affinity to avidin/streptavidin/neutravidin proteins; however, such binding characteristics are general chemical knowledge and are not item-specific validation data.