Fmoc-PEG4-hydroxy - ≥98%

Cat. No.: F595706

GRADE & PURITY ≥98%

Storage

Store at -20°C

Shipped In

Ice chest + Ice pads

Application

227,228,229

Specifications

Spezifikationen & Reinheit

≥98%

Storage

Store at -20°C

Verschickt in

Ice chest + Ice pads

Dieses Produkt erfordert Kühlkettenversand. Grundversand und andere Economy-Optionen sind nicht verfügbar.

Reinheit

≥98%

Application Protocols

No validated immunoassay or bioassay protocols are specified for this item. For synthetic use, representative, non-item-specific procedures include:

• Stock solution preparation: dissolve in anhydrous DMF, DCM, or DMSO to 0.05–0.5 M under inert atmosphere. Filter if needed.
• Fmoc deprotection test: Treat a small aliquot with 20% piperidine/DMF (v/v) for 5–10 min at rt; analyze by LC–MS to confirm release of the Fmoc fragment and preservation of the PEG chain.
• Tosylate formation: To a cooled (0 °C) solution in dry DCM, add Et3N (3 eq) and catalytic DMAP, then TsCl (1.3 eq). Stir to rt for 2 h; quench with aqueous NaHCO3, extract, and purify by silica gel using DCM/MeOH (0–5%).

These examples are illustrative; adapt to your substrates and consult primary literature. For research use only.

Biological Roles

This product is a synthetic linker and does not have an intrinsic biological role. However, from a biochemistry perspective (general/literature):

• PEG spacers modulate hydrophilicity, flexibility, and steric separation between biomolecular domains, often reducing nonspecific interactions and improving aqueous behavior of conjugates.
• A PEG4 segment provides a short, flexible tether, balancing conformational freedom with minimal mass addition—useful in enzyme probes, pull-down handles, and affinity tags.
• The Fmoc group is a protecting group without biological function; it is base-labile and can be removed to unveil a primary amine for further bioconjugation (e.g., amide formation to carboxyl-bearing biomolecules or linkers).
• In surface chemistry, PEGylation reduces protein adsorption (“antifouling”) relative to unmodified hydrophobic surfaces; the effect depends on PEG length, density, and architecture (literature).

All uses are for research and laboratory studies; no clinical or therapeutic claims are made or implied.

Buffer Applications

Not typically applicable. Fmoc-PEG4-hydroxy is a synthetic linker/building block rather than a buffering agent. It does not form conventional buffer systems and is generally used in organic media for derivatization and conjugation steps. For experimental workflows, prepare standard biochemical buffers (e.g., PBS, HEPES) separately and introduce the linker via compatible organic stock solutions (e.g., DMF, DMSO) at controlled percentages to avoid precipitation or denaturation of biomolecules.

Green Alternatives

Greener solvent choices (general guidance)

• Traditional workflows rely on DMF and DCM. Consider substituting with greener media where feasible:

• N-Butylpyrrolidone (NBP) or propylene carbonate (PC): effective replacements for DMF in many coupling and derivatization steps; higher flash points, lower toxicity profiles (literature).

• 2-Methyltetrahydrofuran (2-MeTHF) or CPME: alternatives to THF/DCM for sulfonylation and carbonate chemistry; improved safety and renewable sourcing (2-MeTHF).

• Ethyl acetate or i-PrOAc: greener eluents for chromatography in place of DCM; often with small alcohol modifiers to manage PEG tailing.

Process considerations and trade-offs

• Solubility: Fmoc–PEG linkers dissolve well in DMF/DCM; greener solvents may require temperature elevation or co-solvents.
• Reaction rates/selectivity: Base-promoted steps (e.g., Ms/Ts formation, SN2) can slow in highly viscous carbonates (PC). Agitation and temperature control mitigate this.
• Workup: Greener solvents can simplify waste handling and reduce halogenated waste streams.

Example comparison (literature, non-item-specific)

• DMF → NBP: similar polarity and performance; NBP is less volatile and has a better EHS profile.
• DCM → EtOAc/2-MeTHF: avoids chlorinated waste; may need slightly longer reaction times or higher equivalents.

Adopt greener alternatives after verifying compatibility with your specific substrates and analytics.

Pharmaceutical Uses

No pharmacopeial grade or excipient designation is specified for this item; refer to CoA/Spec Sheet. General, non-clinical context:

• Linker for research-stage conjugates: PEG4 spacers are frequently explored in discovery-scale ADCs, PROTACs, and imaging agent prototypes to tune polarity and spacing between pharmacophores. The Fmoc protection allows stepwise assembly then base-mediated deprotection to expose an amine for final coupling.
• Formulation/process role: In R&D, such linkers are typically intermediates, not final excipients. They may be handled in DMF/NMP/DCM during synthesis and then removed or transformed before any biological testing.
• Regulatory note: Any use toward GMP or clinical manufacture requires comprehensive qualification of identity, purity, residual solvents, and elemental impurities according to relevant guidelines; this product is offered for research use only and not intended for use in humans or diagnostic procedures.

Physical Properties

Item-specific specifications

• Melting point, boiling point, density, refractive index, water/peroxide/metal limits, UV cutoff: Not specified for this item; refer to CoA/Spec Sheet.

General/literature-based characteristics (non-spec)

• Physical form: typically a white to off-white solid for comparable Fmoc–PEG linkers (literature).
• Solubility profile: good solubility in polar aprotic organic solvents such as DMF, NMP, DMSO, dichloromethane, and THF; moderate in acetonitrile and methanol; poor in water unless aided by base or co-solvent (literature). The hydrophobic Fmoc group can reduce aqueous solubility despite the PEG segment.
• Acid/base behavior: Fmoc carbamate is base-labile; terminal –OH is weakly acidic (pKa of alcohols typically ~15–16 in water; literature). No strong ionizable groups present under neutral conditions.
• Partitioning: Amphiphilic due to PEG chain and aromatic Fmoc; overall behavior is solvent-dependent (literature, no item-specific logP).
• Spectroscopic features: Fmoc chromophore shows characteristic UV absorbance around 254–265 nm and near 300 nm (literature), useful for monitoring Fmoc deprotection; these are not certified specifications for this item.

Always consult the product-specific CoA/SDS for definitive physical data and handling limits.

Quality and Grades

Item-specific grade/purity

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

Context and expectations (general)

• For linker building blocks used in conjugation and SPPS workflows, common quality indicators include assay purity (HPLC), identity (1H/13C NMR, MS), residual solvents, and water content (KF). UV trace at 214/254/280 nm is often reviewed for chromatographic purity of Fmoc-bearing materials.
• Low moisture is desirable to maximize activation and coupling efficiency, particularly when converting the terminal alcohol to reactive intermediates (e.g., tosylates, carbonates, NHS derivatives).
• If designated as “peptide synthesis” or “bioconjugation” grade by the supplier (not specified here), this typically implies enhanced control of trace acids/bases and low UV-absorbing impurities that could complicate monitoring of Fmoc release.

Stabilizers/additives

• None are specified for this item. If stabilizers are present for other catalog entries, they should be declared on the CoA/Spec Sheet.

Please refer to the item’s CoA/Spec Sheet for concrete specifications and analytical data.

Reaction and Applications

Typical uses (general/literature)

• Spacer/linker in bioconjugation: Introduces a defined PEG4 distance between functional domains in probes, affinity tags, and materials surfaces.
• PROTACs and heterobifunctional conjugates: The terminal alcohol can be transformed into reactive handles (e.g., tosylate/mesylate → azide → click; carbonate → carbamate/urethane) while Fmoc masks the amine, enabling sequential, chemoselective assembly.
• Surface and polymer modification: Grafting onto nanoparticles, resins, or planar substrates after converting –OH to a coupling-compatible group (e.g., succinate or p-nitrophenyl carbonate).
• Peptide and peptoid chemistry: Provides hydrophilic spacing between peptide motifs or between peptide and reporter groups; Fmoc deprotection with base (e.g., piperidine) unveils the amine for subsequent acylation.

Practical tips

• Keep reactions anhydrous; PEG chains are hygroscopic. Dry solvents and use molecular sieves where appropriate.
• Monitor Fmoc integrity: avoid unintended base exposure during steps meant to preserve the protected amine.
• For azide installation: convert –OH → Ms/Ts (MsCl/TsCl, Et3N, 0–25 °C) then SN2 with NaN3 in DMF at 50–80 °C (literature). Subsequent CuAAC with alkynes builds triazoles efficiently.
• For carbonate activation: treat with DSC or CDI in DMF/THF with catalytic DMAP; couple to nucleophiles (amines/phenols) to form carbamates/carbonates.

All applications are for research and laboratory use only.

Reaction Conditions

General literature guidance for common transformations of Fmoc-PEG4-hydroxy (non-item-specific; optimize per substrate):

• Fmoc deprotection: 20% piperidine in DMF, rt, 5–20 min for solid-phase or solution-phase work; monitor by UV (Fmoc byproduct absorbance near 301 nm). Alternative bases: 20% morpholine or DBU mixtures for more challenging matrices.
• Tosylation/mesylation of terminal –OH: TsCl or MsCl (1.2–1.5 eq), Et3N (2–3 eq), catalytic DMAP in dry DCM or THF, 0 °C → rt, 1–3 h. Work under anhydrous conditions to suppress hydrolysis.
• Azide substitution: NaN3 (2–4 eq) in DMF or DMSO, 50–80 °C, 2–12 h. Follow by reduction (Staudinger or catalytic hydrogenation) if an amine is desired.
• Carbonate activation: CDI (1.2–1.5 eq) or DSC (1.2–1.5 eq) with catalytic DMAP in DMF/THF, rt to 40 °C, 1–4 h; couple with amines/phenols to form carbamates/carbonates.
• Appel-type halogenation: PPh3/CBr4 or PPh3/CCl4 in DCM, 0 °C → rt; consider PEG sensitivity to extensive halogenated waste and use greener alternatives where possible.

Typical yields for these steps are moderate to high (literature), but depend strongly on drying, stoichiometry, and workup. Always verify Fmoc integrity by NMR/LC–MS after basic or nucleophilic steps.

Safety and Handling

GHS classification and hazards

• Signal word, hazard statements, pictograms, GHS classes: Not specified for this item; refer to SDS for authoritative information.

General handling guidance (professional lab practice; non-item-specific)

• Avoid inhalation of dust and contact with skin/eyes. Handle in a fume hood when weighing and during reactions that generate volatile bases (e.g., piperidine for Fmoc deprotection).
• Personal protective equipment (PPE): lab coat, safety glasses, and appropriate chemical-resistant gloves (e.g., nitrile). Consider double-gloving for extended handling in DMF/NMP.
• Incompatibilities: Strong bases trigger Fmoc deprotection; strong acids can hydrolyze carbonate linkages. Avoid prolonged exposure to moisture as PEG chains are hygroscopic and water can impact coupling efficiencies.
• First aid (summary; defer to SDS): on skin/eye contact, rinse with water for ≥15 min and remove contaminated clothing; if inhaled, move to fresh air; if ingested, rinse mouth and seek medical attention.
• Spill response: Collect solids by gentle sweeping; for solutions, absorb with inert material. Dispose of waste according to institutional and local regulations.
• Fire safety: Combustible organic; use CO2, dry chemical, or foam. Combustion may yield carbon oxides and irritants from protecting groups.

Always consult the SDS before use. For research use only.

Solvent Selection

Polarity and miscibility (general/literature)

• The amphiphilic nature (aromatic Fmoc + PEG4 chain) affords excellent solubility in polar aprotic solvents used in peptide/conjugation chemistry: DMF, NMP, DMSO, DCM, THF. Limited solubility in acetonitrile and alcohols; typically insoluble or only sparingly soluble in pure water.

Choosing solvents by task

• Coupling/derivatization of the terminal –OH: DMF or DCM are common. For sulfonylation (TsCl/MsCl), dry DCM, THF, or toluene with a base (e.g., Et3N) are typical.
• Carbonate formation (e.g., DSC, CDI): anhydrous DMF, THF, or DCM provide good performance; maintain low water to avoid premature hydrolysis.
• Workup/purification: Products often precipitate from cold ether/hexanes mixtures; flash chromatography on silica using DCM/MeOH or DCM/EtOAc gradients is common. PEG tails can cause tailing—adding a small % of MeOH or i-PrOH can sharpen bands.

Comparison (general guidance)

• DMF vs NMP: NMP offers higher bp and often better solubility; DMF is more volatile and easier to remove. Both are effective for Fmoc chemistry.
• DCM vs THF: DCM excels for sulfonylation and rapid extractions; THF offers better compatibility with bases and low temperatures.

Note: No item-specific solvent restrictions are provided; consult the SDS/CoA and your process requirements.

Storage and Reconstitution

Item-specific storage

• Storage conditions: Store at -20°C (per Product Data).
• Shipping: Ice chest + Ice pads (per Product Data).

General handling guidance

• Protect from moisture and prolonged light. Allow container to warm to room temperature in a desiccator before opening to minimize condensation.
• Reseal promptly under dry inert gas if possible. Consider aliquoting to minimize freeze–thaw and headspace moisture ingress.
• For solution stocks, prepare in anhydrous DMF, DMSO, DCM, THF, or NMP. Store solutions at ≤–20 °C when feasible; check stability before long-term storage. Avoid basic additives unless intentionally deprotecting Fmoc.

Reconstitution (non-item-specific)

• Target concentrations: 50–500 mM are typical for linker stocks depending on application. Vortex and, if needed, gently warm (≤40 °C) to aid dissolution. Filter (PTFE, 0.2 µm) for moisture/particulate control.
• Stability check: verify by LC–MS or HPLC before use in critical steps, especially after extended storage.

Follow the CoA/SDS for any additional, item-specific instructions. For research use only.

Structure and Identity

Item-specific identifiers

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

Structural description (general/literature)

• Fmoc-PEG4-hydroxy is a monofunctional polyethylene glycol linker bearing an N-Fmoc-protected amino moiety at one end and a free primary alcohol at the other. A common representation is Fmoc–NH–(CH2CH2O)4–CH2CH2–OH (PEG4 denotes four ethylene glycol repeat units).
• Key functional groups: fluorenylmethoxycarbonyl (carbamate-protected amine), polyether chain (PEG), terminal primary alcohol.
• Ring systems: Fmoc contains a fused bicyclic fluorene aromatic system.
• Stereochemistry: none (achiral backbone; no defined stereocenters).
• Linker length: PEG4 typically provides a spacer length in the ~18–22 Å range between termini (literature, depends on conformation and environment).

Notes

• “Fmoc” is base-labile; the terminal OH is available for further derivatization (e.g., carbonate/ester formation, sulfonate activation).

Synthetic Utility

Functional handles and transformations (general/literature)

• Protected amine end: Fmoc–NH– is unreactive toward mild electrophiles under neutral conditions; deprotect with secondary amines (e.g., 20% piperidine in DMF) to reveal –NH2 for amide coupling (HATU/EDC/HOAt, etc.).
• Alcohol end: versatile conversion to leaving groups (Ms/Ts, halides via Appel or PBr3/PPh3/CBr4 variants), to azides (SN2), to carbonates/urethanes (CDI/DSC) enabling subsequent coupling to nucleophiles.
• PEG backbone: confers solubility and flexibility; compatible with click chemistry sequences and late-stage diversification.

Retrosynthetic value

• Serves as a modular spacer between two functional motifs. In retrosynthesis, disconnect at the carbonate/amide junctions to standardize assembly from readily available building blocks (acids, amines, phenols).

Named/representative tactics

• Williamson-type etherifications after installing a suitable leaving group at the alcohol terminus.
• Mitsunobu reactions with sensitive nucleophiles (after careful selection to avoid Fmoc cleavage).
• CuAAC after azide installation to build triazole-linked conjugates.

Maintain orthogonality: plan sequences so that base exposure is reserved for the Fmoc deprotection step, protecting other base-labile fragments accordingly.

Target Specificity

Not applicable. This product is a small-molecule linker and does not have biological target specificity parameters (e.g., antigen, species reactivity, clone, isotype).