Protein Modification Reagents
Medchemexpress LLC Amino-PEG4-CH2COOH | 195071-49-9 | ≥98.0% | 251.28 g/mol | C10H21NO6 | 250 MG
Amino-PEG4-CH2COOH is a four-unit polyethylene glycol (PEG4) linker bearing a terminal amino group and a carboxylic acid (-CH2COOH). It is used as a hydrophilic spacer in bioconjugation chemistries such as PROTAC and antibody-drug conjugate (ADC) synthesis.
- Four-unit PEG spacer providing flexibility and solubility.
- Terminal amino and carboxylic acid functionalities for straightforward conjugation.
- High chemical purity suitable for research applications.
- Molecular weight approximately 251.28 g/mol, formula C10H21NO6.
- Available in common lab pack sizes, including 250 MG for small-scale synthesis.
Medchemexpress LLC Dbco-peg4-pfp ester | 2182601-19-8 | 95.0% | C36H35F5N2O8 | 100 MG
DBCO-PEG4-PFP ester is a PEG-based PROTAC linker utilized in the synthesis of PROTACs. It functions as a click chemistry reagent, containing a DBCO group that facilitates strain-promoted alkyne-azide cycloaddition (SPAAC) with azide-containing molecules. This allows it to leverage the intracellular ubiquitin-proteasome system for selective degradation of target proteins.
- Peg-based protac linker
- Utilized in protac synthesis
- Functions as a click chemistry reagent
- Contains a dbco group for spaac reactions
- Facilitates selective degradation of target proteins
- Appears as a colorless to light yellow oil
- Purity of 95.0%
- Molecular weight: 718.66
- Molecular formula: C36H35F5N2O8
Medchemexpress LLC Fmoc-NH-PEG3-CH2CH2COOH | 867062-95-1 | MFCD06656471 | 99.8% | 443.49 g/mol | C24H29NO7 | 100 MG
Fmoc-NH-PEG3-CH2CH2COOH is a PEG-based, Fmoc-protected heterobifunctional linker designed for use in antibody-drug conjugate (ADC) and proteolysis-targeting chimera (PROTAC) construction. It features an Fmoc-protected amine and a terminal carboxylic acid that enable standard peptide-coupling and conjugation chemistries.
- Fmoc-protected amine enabling orthogonal deprotection
- Terminal carboxylic acid for amide coupling
- Molecular formula C24H29NO7 and molecular weight 443.49 g/mol
- Cas number 867062-95-1
- Purity 99.8%
- Available in small-scale packages such as 100 MG
- Storage: pure form -20°C (3 years) or 4°C (2 years); in solvent -80°C (6 months)
- Suitable for ADC and PROTAC linker synthesis and bioconjugation
Medchemexpress LLC Tos-PEG5-CH2COOtBu | 1949793-62-7 | C23H38O10S | 1 G
Tos-PEG5-CH2COOtBu is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs. Its applications include cancer-programmed cell death.
- Can be used in the synthesis of PROTACs.
- Applications include cancer-programmed cell death.
- Research area is cancer.
- Targets PROTAC linkers.
eMolecules 1807540-84-6 | Mal-amido-PEG4-TFP ester | Broadpharm | MFCD28505515 | 564.487 | C24H28F4N2O9 | 95.000 | Fc1cc(F)c(F)c(OC(=O)CCOCCOCCOCCOCCNC(=O)CCN2C(=O)C=CC2=O)c1F | 5g | 550804212
Mal-amido-PEG4-TFP ester | Broadpharm | 1807540-84-6 | MFCD28505515 | 564.487 | C24H28F4N2O9 | 95.000 | Fc1cc(F)c(F)c(OC(=O)CCOCCOCCOCCOCCNC(=O)CCN2C(=O)C=CC2=O)c1F | 5g | 550804212
![eMolecules 2140807-42-5 | (S, R, S)-AHPC-PEG3-acid | Broadpharm662.800 | C32H46N4O9S | 0.000 | Cc1ncsc1-c1ccc(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)CCOCCOCCOCCC(O)=O)C(C)(C)C)cc1 | 500mg | 528284338](https://assets.fishersci.com/TFS-Assets/CCG/product-images/502183539.JPG-250.jpg)
eMolecules 2140807-42-5 | (S, R, S)-AHPC-PEG3-acid | Broadpharm662.800 | C32H46N4O9S | 0.000 | Cc1ncsc1-c1ccc(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)CCOCCOCCOCCC(O)=O)C(C)(C)C)cc1 | 500mg | 528284338
(S, R, S)-AHPC-PEG3-acid | Broadpharm | 2140807-42-5662.800 | C32H46N4O9S | 0.000 | Cc1ncsc1-c1ccc(CNC(=O)[C@@H]2C[C@@H](O)CN2C(=O)[C@@H](NC(=O)CCOCCOCCOCCC(O)=O)C(C)(C)C)cc1 | 500mg | 528284338
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 3,6,9,12-tetraoxatridecan-1-amine | 85030-56-4 | 98.8% | 207.27 g/mol | C9H21NO4 | 5 G
m-PEG4-Amine is a methoxy-terminated polyethylene glycol (PEG4) linker with a terminal primary amine used as a cleavable linker for antibody-drug conjugates (ADCs) and as a PEG-based linker in PROTAC synthesis. The compound has CAS 85030-56-4, molecular weight 207.27 g/mol, and is typically supplied as a colorless to light yellow liquid.
- Primary amine functional group suitable for conjugation chemistry.
- Methoxy-terminated PEG4 spacer provides solubility and flexibility.
- Cleavable linker applications for ADC and PROTAC synthesis.
- Stable when stored protected from light at recommended temperatures.
- Colorless to light yellow liquid, easy to handle in solution-phase chemistry.
Medchemexpress LLC Folic acid-PEG5-maleimide | 00-00-0 | 99.5% | 783.78 g/mol | C35H45N9O12 | 5 MG
FA-PEG5-Mal (folic acid-PEG5-maleimide) is a polyethylene glycol-based bifunctional linker that combines a folic acid recognition unit with a terminal maleimide for thiol coupling. It is intended for use in the synthesis of PROTACs and folate-targeted conjugates, providing a water-soluble spacer to connect ligands for targeted degradation or delivery.
- Provides a folic acid recognition unit for folate receptor targeting.
- Features a terminal maleimide for selective thiol conjugation.
- Uses a PEG5 spacer to impart water solubility and flexibility.
- High purity suitable for research-grade chemical synthesis.
- Available in small milligram packages for conjugation workflows.
- Stable when stored sealed and protected from moisture and light; in solvent: -80°C (6 months), -20°C (1 month).
![eMolecules DSPE-CH2-PEG-Fluor 488, MW 2,000 | Broadpharm |1387.620 | C66H100N4NaO20PS2 | 98.000 | [Na+].CCCCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCCNC(=O)COCCNC(=O)c1ccc(c(c1)C(O)=O)-c1c2ccc(N)c(c2oc2c(c(=[NH2+])ccc12)S([O-])(=O)=O)S(O)(=O)=O)OC(=O)CCCCCCCCCCCCCCCCC | 5mg | 798870817](https://assets.fishersci.com/TFS-Assets/CCG/product-images/502472815.JPG-250.jpg)
eMolecules DSPE-CH2-PEG-Fluor 488, MW 2,000 | Broadpharm |1387.620 | C66H100N4NaO20PS2 | 98.000 | [Na+].CCCCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCCNC(=O)COCCNC(=O)c1ccc(c(c1)C(O)=O)-c1c2ccc(N)c(c2oc2c(c(=[NH2+])ccc12)S([O-])(=O)=O)S(O)(=O)=O)OC(=O)CCCCCCCCCCCCCCCCC | 5mg | 798870817
DSPE-CH2-PEG-Fluor 488, MW 2,000 | Broadpharm |1387.620 | C66H100N4NaO20PS2 | 98.000 | [Na+].CCCCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCCNC(=O)COCCNC(=O)c1ccc(c(c1)C(O)=O)-c1c2ccc(N)c(c2oc2c(c(=[NH2+])ccc12)S([O-])(=O)=O)S(O)(=O)=O)OC(=O)CCCCCCCCCCCCCCCCC | 5mg | 798870817
Medchemexpress LLC Dbco-PEG4-VA-PBD | 2241644-09-5 | MFCD00012576 | 99.7% | 1430.60 g·mol⁻1 | C80H87N9O16 | 5 MG
DBCO-PEG4-VA-PBD is a click chemistry reagent and drug-linker conjugate used to attach pyrrolobenzodiazepine (PBD) payloads to biomolecules via strain-promoted alkyne-azide cycloaddition (SPAAC). It contains a DBCO moiety, a PEG4 spacer, and a valine-alanine cleavable linker designed for antibody-drug conjugate (ADC) assembly.
- Functions as a SPAAC-compatible click chemistry reagent.
- Contains a PEG4 spacer and a valine-alanine cleavable linker.
- Includes a pyrrolobenzodiazepine (PBD) cytotoxic payload.
- High purity suitable for research applications.
- Contains a single defined molecular formula and molecular weight for characterization.
- Intended for research use in bioconjugation and ADC development.
Medchemexpress LLC Methyltetrazine-PEG4-amine hydrochloride | 2245150-18-7 | MFCD31813569 | 99.5% | C17H26ClN5O4 | 10MG
Methyltetrazine-PEG4-amine hydrochloride is a PEG4-linked primary amine functionalized with a methyltetrazine group, provided as the hydrochloride salt. It functions as a click-chemistry reagent that undergoes rapid inverse-electron-demand Diels-Alder (iEDDA) reactions with trans-cyclooctene (TCO) partners, enabling bioorthogonal labeling and site-specific conjugation in bioconjugation workflows. Supplied as a solid (purplish red to red) with high purity; store sealed at 4°C.
- Enables rapid iEDDA click reactions with TCO partners.
- PEG4 spacer improves solubility and flexibility.
- Terminal primary amine allows straightforward conjugation chemistry.
- Hydrochloride salt form enhances stability for storage.
- High purity (~99.5%) suitable for labeling and conjugation.
- Solid form, easy to handle and store at 4°C.
Medchemexpress LLC Mal-amido-PEG2-NHS ester | 955094-26-5 | MFCD11041137 | 99.3% | 425.39 g/mol | C18H23N3O9 | 50 MG
Mal-amido-PEG2-NHS ester is a noncleavable ADC linker containing a maleimide reactive group and an N-hydroxysuccinimide (NHS) ester. The NHS ester labels primary amines (-NH2) to form stable amide bonds, while the maleimide enables thiol conjugation for bioconjugation and linker chemistry applications.
- Noncleavable ADC linker with maleimide and NHS ester.
- Reacts with primary amines to form stable amide bonds.
- Enables thiol conjugation via the maleimide functionality.
- High purity suitable for research-grade bioconjugation.
- Supplied as a solid for easy handling and storage.