Protein Modification Reagents
Medchemexpress LLC 6-FAM-PEG3-azide | 412319-45-0 | 98.1% | C29H28N4O9 | 10MG
6-FAM-PEG3-Azide is a fluorescent labeling reagent composed of a 6-carboxyfluorescein (6-FAM) dye linked to an azide via a PEG3 spacer. It is designed for covalent conjugation to alkyne-functionalized partners using copper-catalyzed azide-alkyne cycloaddition (CuAAC) or strain-promoted azide-alkyne cycloaddition (SPAAC), enabling fluorescent labeling of oligonucleotides and other biomolecules.
- Fluorescent labeling with excitation 498 nm and emission 532 nm.
- PEG3 spacer improves water solubility and reduces steric hindrance.
- Azide functional group for CuAAC and SPAAC click chemistry.
- Solid, light yellow to yellow form stable when stored as powder at -20°C.
- High purity (~98.1%) suitable for analytical and labeling applications.
Medchemexpress LLC DSPE-N3 | 2839508-98-2 | 96.4% | 831.11 g·mol⁻¹ | C43H83N4O9P | 25 MG
DSPE-N3 is an azide-functionalized phospholipid used as a click-chemistry reagent in biochemical and nanotechnology research. It enables both copper-catalyzed and strain-promoted azide-alkyne cycloadditions for reliable conjugation of biomolecules, surface modification, and lipid nanoparticle functionalization.
- Azide-functionalized phospholipid enabling click chemistry conjugation.
- Compatible with CuAAC and SPAAC reaction conditions.
- Suitable for nanoparticle and surface functionalization applications.
- White to off-white solid with standard storage requirements.
- Soluble in DMSO with warming and sonication for formulation.
- High purity (~96.4%) appropriate for research use.
![eMolecules Bromo-PEG1-azide | Broadpharm | 1144106-65-9 | | 194.032 | C4H8BrN3O | 98.000 | BrCCOCCN=[N+]=[N-] | 1g | 433947074](https://assets.fishersci.com/TFS-Assets/CCG/product-images/NC1691006.jpg-250.jpg)
eMolecules Bromo-PEG1-azide | Broadpharm | 1144106-65-9 | | 194.032 | C4H8BrN3O | 98.000 | BrCCOCCN=[N+]=[N-] | 1g | 433947074
Bromo-PEG1-azide | Broadpharm | 1144106-65-9 | | 194.032 | C4H8BrN3O | 98.000 | BrCCOCCN=[N+]=[N-] | 1g | 433947074
eMolecules PTDA-PEG4-Azide | | | 250mg
Broadpharm | PTDA-PEG4-Azide | 250mg | 573896753 | BP-25451 | 98.000 | | | 539.546 | C22H33N7O9
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Medchemexpress LLC m-PEG5-succinimidyl carbonate | 1058691-00-1 | 98.0% | 393.39 g/mol | C16H27NO10 | 25 MG
m-PEG5-succinimidyl carbonate is a monomethoxy polyethylene glycol (PEG) linker with five ethylene glycol units terminated as a succinimidyl carbonate active ester. It is supplied as a reactive linker for conjugation to primary amines in bioconjugation workflows.
- Non-cleavable 5-unit PEG spacer for conjugation.
- Activated succinimidyl carbonate for efficient amine coupling.
- Suitable for ADC and PROTAC synthesis applications.
- Appearance: colorless to light yellow liquid; supplied in small mg quantities for research use.
Medchemexpress LLC Propargyl-PEG4-GGFG-DXd | 2762518-94-3 | 100.0% | 1083.12 g/mol | C54H63FN8O15 | 50 MG
Propargyl-PEG4-GGFG-DXd is a drug-linker conjugate for antibody-drug conjugate (ADC) research that combines a cleavable GGFG-PEG4 linker with a propargyl reactive group and the DNA topoisomerase I inhibitor DXd as the payload. This compound is supplied for research use only and is intended for conjugation and ADC development studies.
- High stated purity suitable for research applications
- Contains a propargyl functional group for click chemistry conjugation
- Includes a cleavable GGFG linker designed for payload release
- Payload is a topoisomerase I inhibitor (DXd) for cytotoxic activity
- Available in multiple pack sizes for small-scale research
- Supplied for research use only, not for human use
Medchemexpress LLC Cy3-peg-biotin | 95.0% | 2000 (average) | 10 MG
Cy3-PEG-biotin is a polyethylene glycol conjugate bearing a Cy3 fluorescent dye and a biotin affinity tag; it is designed for fluorescence labeling and capture of biomolecules via biotin-streptavidin interactions for microscopy, flow cytometry, and nucleic acid or protein labeling.
- Provides Cy3 fluorescence for detection (max emission ≈ 562-570 nm).
- Biotin tag enables high-affinity capture by streptavidin/avidin.
- PEG spacer (average MW 2000) improves solubility and reduces steric hindrance.
- Available in small laboratory quantities suitable for labeling workflows.
![Medchemexpress LLC Ethanol, 2-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethoxy] tosylate | 236754-49-7 | 99.3% | 417.48 g/mol | C17H27N3O7S | 500 MG](https://assets.fishersci.com/TFS-Assets/CCG/product-images/5000203783.png-250.jpg)
Medchemexpress LLC Ethanol, 2-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethoxy] tosylate | 236754-49-7 | 99.3% | 417.48 g/mol | C17H27N3O7S | 500 MG
Azide-PEG5-Tos is a cleavable PEG-based linker bearing an azide functional group and a tosylate leaving group. It is used as a click-chemistry handle and linker in the synthesis of antibody-drug conjugates and other bioconjugation applications. The reagent is supplied as a solid and is typically dissolved in DMSO for reactions.
- Cleavable 5-unit polyethylene glycol spacer
- Contains an azide functional group for copper-catalyzed azide-alkyne cycloaddition
- Contains a tosylate leaving group for downstream modification
- High purity suitable for synthetic chemistry applications
- Stable under cold storage when handled per supplier recommendations
Medchemexpress LLC Fmoc-NH-PEG4-CH2COOH | 437655-95-3 | 99.1% | 473.52 | C25H31NO8 | 5 G
Fmoc-NH-PEG4-CH2COOH is an Fmoc-protected PEG4 linker bearing a terminal carboxylic acid. It is used as a cleavable ADC linker and as a PEG-based PROTAC linker for conjugation and linker synthesis. The compound has molecular formula C25H31NO8 and molecular weight 473.52 and is supplied at high purity for research use.
- Fmoc-protected amine compatible with solid-phase and solution-phase synthesis.
- Terminal carboxylic acid enables standard coupling reactions.
- Peg4 spacer increases solubility and provides linker flexibility.
- High purity suitable for research and conjugation chemistry.
- Available in multiple sizes, including a 5 g package.
eMolecules Broadpharm / Propargyl-PEG1-SS-PEG1-PFP ester / 50mg / 296213404 / BP-22910 / 98.000 / 1817735-30-0 / MFCD29042354 / 430.400 / C16H15F5O4S2
Broadpharm / Propargyl-PEG1-SS-PEG1-PFP ester / 50mg / 296213404 / BP-22910 / 98.000 / 1817735-30-0 / MFCD29042354 / 430.400 / C16H15F5O4S2
eMolecules Fmoc-PEG3-NHS ester | 1352827-47-4 | MFCD28142471 | 1g
Broadpharm | Fmoc-PEG3-NHS ester | 1g | 263744723 | BP-22334 | 98.000 | 1352827-47-4 | MFCD28142471 | 540.569 | C28H32N2O9
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Medchemexpress LLC Mal-PEG2-Val-Cit-PABA | 1662687-83-3 | 98.9% | 590.63 | C27H38N6O9 | 5 MG
Mal-PEG2-Val-Cit-PABA is a cleavable antibody-drug conjugate (ADC) linker designed for synthesis of ADCs. It features a maleimide reactive handle, a PEG2 spacer for improved hydrophilicity, and a Val-Cit-PABA cleavage motif that enables protease-mediated release of payloads in target cells.
- Cleavable Val-Cit-PABA motif for protease-triggered payload release.
- Maleimide functional group for thiol-selective conjugation to antibodies.
- PEG2 spacer increases hydrophilicity and may reduce aggregation.
- High chemical purity suitable for research and ADC synthesis.
- Stable when stored as powder at -20°C; follow recommended solvent storage conditions.
Medchemexpress LLC Azide-PEG5-Tos | 236754-49-7 | MFCD28505520 | >98.0% | 417.48 | C17H27N3O7S | 25 G
Azide-PEG5-Tos is an azide-functional polyethylene glycol (PEG) linker consisting of five ethylene glycol units and a tosylate leaving group. It is designed for bioconjugation applications such as antibody-drug conjugate (ADC) synthesis and click chemistry, and is supplied for research use only.
- Cleavable 5-unit PEG linker suitable for ADC and PROTAC synthesis.
- Azide functional group enables copper-catalyzed and strain-promoted azide-alkyne cycloaddition.
- High solubility in DMSO (≥100 mg/mL) and compatible with common in vivo vehicles at ≥2.5 mg/mL.
- Tosylate leaving group allows for further nucleophilic substitution reactions.
- Recommended storage: pure solid at -20°C (long term) or 4°C (short term).
Medchemexpress LLC BCN-endo-PEG2-maleimide | 2675364-08-4 | 98.1% | 475.53 | C24H33N3O7 | 25 MG
A bifunctional linker reagent containing an endo-bicyclononyne reactive group and a maleimide separated by a PEG2 spacer, designed for strain-promoted azide-alkyne cycloaddition and thiol conjugation in bioconjugation and drug-delivery workflows.
- Contains endo-bicyclononyne and maleimide reactive groups.
- Peg2 spacer provides flexibility and solubility.
- Enables catalyst-free strain-promoted azide-alkyne cycloaddition (SPAAC) with azides.
- Compatible with maleimide-mediated thiol conjugation.
- High purity and defined molecular weight for reproducible conjugation.