Protein Modification Reagents
eMolecules Benzyl-PEG2-CH2CO2tBu | 1309451-06-6 | MFCD28015768 | 1g
Broadpharm | Benzyl-PEG2-CH2CO2tBu | 1g | 247403047 | BP-22150 | 98.000 | 1309451-06-6 | MFCD28015768 | 266.337 | C15H22O4
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eMolecules m-PEG24-alcohol | 9004-74-4 | MFCD27977524 | 1g
Broadpharm | m-PEG24-alcohol | 1g | 229582254 | BP-22074 | 97.000 | 9004-74-4 | MFCD27977524 | 1089.314 | C49H100O25
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eMolecules Fmoc-NH-PEG6-CH2COOH | 437655-96-4 | MFCD26142983 | 1g
Broadpharm | Fmoc-NH-PEG6-CH2COOH | 1g | 340377165 | BP-23534 | 95.000 | 437655-96-4 | MFCD26142983 | 561.628 | C29H39NO10
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Medchemexpress LLC Tos-PEG5-CH2COOtBu | 1949793-62-7 | MFCD30828689 | ≥95% | C23H38O10S | 100 MG
Tos-PEG5-CH2COOtBu is a PEG linker that contains a t-butyl ester and a tosyl group. The hydrophilic PEG spacer increases solubility in aqueous media, and the t-butyl protected carboxyl group can be deprotected under acidic conditions. The tosyl group serves as an excellent leaving group for nucleophilic substitution reactions. This compound is a PEG-based PROTAC linker used in the synthesis of PROTACs.
- Contains a t-butyl ester and a tosyl group.
- Hydrophilic PEG spacer enhances solubility in aqueous media.
- T-butyl protected carboxyl group can be deprotected under acidic conditions.
- Tosyl group serves as a leaving group for nucleophilic substitution reactions.
- Used as a PEG-based PROTAC linker in PROTAC synthesis.
Medchemexpress LLC PEG(2000)-C-DMG | 1443687-74-8 | 98.0% | 2600 g/mol (approx.) | 10 MG
PEG(2000)-C-DMG is a polyethylene glycol-conjugated lipid used as a PEG-lipid component in liposomes and lipid nanoparticles (LNPs). It helps stabilize particle surfaces, reduce protein adsorption, and modulate circulation time for nucleic acid delivery applications such as siRNA and mRNA formulations. Typical form is a white to off-white solid with solubility in DMSO (requires sonication).
- Improves particle stability and circulation time.
- Reduces serum protein adsorption and aggregation.
- Suitable for lipid nanoparticle and liposome formulations for nucleic acid delivery.
- Supplied as a solid that is soluble in DMSO with sonication.
- High purity for research applications.
Medchemexpress LLC DSPE-PEG-FITC | 1000788-53-3 | 100 MG
DSPE-PEG-FITC (MW 10000) is a fluorescein-labeled DSPE-PEG amphiphilic conjugate (average molecular weight 10,000 Da) that forms micelles in aqueous solution. It is commonly used to prepare fluorescent liposomes and nanoparticles for research in drug delivery and imaging, and is supplied for research use only.
- Provides fluorescein labeling for visualization in fluorescence assays.
- Forms micelles and incorporates into liposome bilayers for nanoparticle formulation.
- Average molecular weight supports steric stabilization and extended circulation.
- Available in laboratory-friendly pack sizes including 100 mg.
- Supplied with supporting documents such as COA and SDS for quality control.
eMolecules Fmoc-Lys (biotin-PEG12)-OH | | | 500mg
Broadpharm | Fmoc-Lys (biotin-PEG12)-OH | 500mg | 272383804 | BP-22614 | 95.000 | | | 1194.440 | C58H91N5O19S
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eMolecules Amino-PEG36-acid | 196936-04-6 | MFCD21363230 | 1g
Broadpharm | Amino-PEG36-acid | 1g | 296213679 | BP-22577 | 97.000 | 196936-04-6 | MFCD21363230 | 1675.002 | C75H151NO38
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Medchemexpress LLC Mal-PEG2-oxyamine TFA | 00-00-0 | MFCD00209801 | 96.5% | C12H17F3N2O7 | 10MG
Mal-PEG2-oxyamine TFA is a PEG-based bifunctional linker supplied as the trifluoroacetic acid (TFA) salt for use in PROTAC synthesis and other bioconjugation applications. It combines a maleimide reactive group with an oxyamine functional handle, and a short PEG2 spacer to enhance solubility and flexibility.
- Bifunctional linker enabling thiol and carbonyl conjugation.
- Maleimide permits rapid, thiol-selective coupling under mild conditions.
- Oxyamine enables chemoselective oxime ligation to aldehydes and ketones.
- PEG2 spacer increases aqueous solubility and reduces steric hindrance.
- Provided as TFA salt to improve stability and handling.
- High purity suitable for research and synthetic workflows.
Medchemexpress LLC TCO-PEG3-Biotin | 570.74 | C27H46N4O7S | 5 MG
TCO-PEG3-Biotin is a cleavable three-unit polyethylene glycol (PEG) linker bearing a trans-cyclooctene (TCO) group and a biotin tag used for click chemistry and antibody-drug conjugate (ADC) synthesis. It enables rapid inverse electron-demand Diels-Alder (iEDDA) ligation with tetrazine partners and supports affinity capture or detection via the biotin handle.
- Cleavable 3-unit PEG linker for bioconjugation.
- Trans-cyclooctene (TCO) group enables inverse electron-demand Diels-Alder (iEDDA) click reactions.
- Biotin tag facilitates affinity capture and detection workflows.
- Molecular weight 570.74 and formula C27H46N4O7S support stoichiometric conjugation planning.
- Available in small milligram quantities suitable for conjugation development and testing.
eMolecules Benzyl-PEG5-CH2CO2tBu | 1807503-89-4 | MFCD28122960 | 1g
Broadpharm | Benzyl-PEG5-CH2CO2tBu | 1g | 254745489 | BP-22255 | 98.000 | 1807503-89-4 | MFCD28122960 | 398.496 | C21H34O7
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eMolecules DNP-PEG3-azide | 951671-87-7 | MFCD30182049 | 500mg
Broadpharm | DNP-PEG3-azide | 500mg | 309208997 | BP-23248 | 98.000 | 951671-87-7 | MFCD30182049 | 384.349 | C14H20N6O7
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Medchemexpress LLC Tetrazine-PEG4-amine hydrochloride | 2752945-36-9 | 99.8% | 470.95 g/mol | C20H31ClN6O5 | 5 MG
Tetrazine-PEG4-amine hydrochloride is a cleavable four-unit polyethylene glycol (PEG) linker containing a tetrazine functional group used as a click-chemistry reagent for inverse electron-demand Diels-Alder (iEDDA) reactions and in the synthesis of antibody-drug conjugates. For research use only.
- Cleavable four-unit PEG linker for ADC synthesis.
- Tetrazine group enables fast iEDDA click chemistry with TCO partners.
- Solid form with high purity (≈99.8%).
- Molecular weight 470.95 g/mol; formula C20H31ClN6O5.
- Soluble in methanol (≈250 mg/mL); may require sonication.
- Store sealed at -20°C; in solution store at -80°C (up to 6 months) or -20°C (up to 1 month).
Medchemexpress LLC Endo-BCN-PEG2-C2-NHS ester | 2243565-12-8 | 95.0% | C22H30N2O8 | 10MG
endo-BCN-PEG2-C2-NHS ester is a PEG-based bifunctional linker for PROTAC construction and bioconjugation. It combines a strained endo-bicyclononyne (BCN) for copper-free click chemistry with an N-hydroxysuccinimide (NHS) ester for selective amine coupling, enabling efficient assembly of bifunctional molecules and protein labeling.
- Contains endo-bicyclononyne (BCN) for strain-promoted azide-alkyne cycloaddition
- Includes an N-hydroxysuccinimide (NHS) ester for rapid amine conjugation
- Incorporates a PEG2 spacer to improve solubility and reduce steric hindrance
- Suitable for PROTAC linker synthesis and bioconjugation workflows
- Molecular formula C22H30N2O8 and molecular weight 450.48 g/mol
Medchemexpress LLC TCO-PEG4-VC-PAB-MMAE | 2758671-45-1 | 99.3% | 1522.91 | C78H127N11O19 | 10 MG
TCO-PEG4-VC-PAB-MMAE is a drug-linker conjugate intended for use in antibody-drug conjugate (ADC) assembly and click-chemistry bioconjugation workflows. It combines a trans-cyclooctene (TCO) click handle, a PEG4-Val-Cit-PAB cleavable linker, and the cytotoxic payload MMAE to enable site-selective conjugation and intracellular release of the payload.
- Provides a trans-cyclooctene (TCO) handle for inverse electron-demand Diels-Alder reactions with tetrazines.
- Contains a PEG4-Val-Cit-PAB cleavable linker for enzymatic payload release.
- Conjugated to MMAE to supply a potent cytotoxic payload for ADC research.
- High purity (99.3%) suitable for research and bioconjugation workflows.
- Characterized by molecular weight 1522.91 and formula C78H127N11O19.