Protein Modification Reagents
Medchemexpress LLC 4-imidazolidinehexanamide, n-(14-amino-3,6,9,12-tetraoxatetradec-1-yl)-5-methyl-2-oxo-, (4R,5S)- | 2306109-91-9 | 99.2% | C20H40N4O6 | 10MG
Amine-PEG4-Desthiobiotin is a PEG-based linker bearing a primary amine and a desthiobiotin moiety used to assemble proteolysis-targeting chimeras (PROTACs), affinity probes, and bioconjugates. The reagent supplies a hydrophilic spacer and a reactive handle to link target-binding ligands to recruiting ligands, supporting modular synthesis and downstream affinity-based workflows.
- Provides a primary amine for straightforward conjugation using standard amide-coupling chemistries.
- Contains a desthiobiotin moiety for reversible affinity capture with streptavidin-based systems.
- PEG4 spacer imparts hydrophilicity and flexible linkage between functional groups.
- High reported purity supports reproducible synthesis and analytical characterization.
- Stable when stored frozen and in solution under recommended conditions.
Medchemexpress LLC Dspe-peg-fitc | 1000788-53-3 | 25 MG
DSPE-PEG-FITC (MW 10,000) is a fluorescein-labeled PEGylated phospholipid designed for incorporation into lipid bilayers and nanoparticle surfaces to enable fluorescence imaging and tracking. The amphiphilic conjugate self-assembles in aqueous environments and is commonly used in liposome and micelle formulation for research applications.
- Provides fluorescent labeling for liposomes and nanoparticles.
- Amphiphilic structure enables incorporation into bilayers and micelles.
- Average PEG molecular weight of approximately 10,000 Da.
- Facilitates visualization and tracking in imaging assays.
- Supplied as a solid that is light sensitive; store protected from light.
Medchemexpress LLC Mal-PEG-mal (MW 2000) | 98.4% | 100 MG
Mal-PEG-mal (MW 2000) is a PEG-based PROTAC linker used in the synthesis of PROTACs. These compounds contain two different ligands connected by a linker; one targets an E3 ubiquitin ligase, and the other targets a specific protein. PROTACs leverage the intracellular ubiquitin-proteasome system to selectively degrade target proteins.
- PEG-based PROTAC linker
- Used in the synthesis of PROTACs
- Contains two different ligands connected by a linker
- Ligands target E3 ubiquitin ligase and target protein
- Utilizes the intracellular ubiquitin-proteasome system
- Selectively degrades target proteins
Medchemexpress LLC Endo-BCN-PEG3-maleimide | 2141976-33-0 | MFCD31811466 | 98.5% | 519.59 g/mol | C26H37N3O8 | 5 MG
endo-BCN-PEG3-maleimide is a heterobifunctional PEG3 linker that pairs an endo-bicyclononyne (BCN) for strain-promoted azide-alkyne cycloaddition with a maleimide for thiol-selective conjugation. The short PEG3 spacer improves solubility and flexibility, making the reagent suitable for bioconjugation, PROTAC linker assembly, and crosslinking in research applications. Supplied as a colorless to light yellow oil with high reported purity and recommended cold storage.
- Strain-promoted azide-alkyne cycloaddition reactivity (BCN).
- Maleimide-based thiol conjugation for cysteine targeting.
- PEG3 spacer improves solubility and flexibility.
- High purity suitable for research use.
- Stable under low-temperature storage conditions.
- Soluble in common organic solvents such as DCM, THF, ACN, DMF, and DMSO.
Medchemexpress LLC Biotin-PEG-azide | 956494-20-5 | MFCD21363314 | 98.7% | 2000 Da | C58H112N6O25S | 25 MG
Biotin-PEG-azide (MW 2000) is a biotin-labeled polyethylene glycol derivative with a terminal azide group designed for efficient azide-alkyne click conjugation. It improves solubility and reduces nonspecific binding while providing a biotin handle for affinity capture and detection. Supplied as a powder, it is commonly used to label proteins, peptides, and probes for biochemical and analytical workflows.
- Biotin tag for streptavidin-based capture and detection.
- Terminal azide for click chemistry conjugation.
- Average molecular weight 2000 Da for spacer and solubility.
- High purity (~98.7%) for reliable labeling.
- Powder form with recommended storage at -20°C.
- Suitable for labeling proteins, peptides, and probes.
eMolecules 2601437-72-1 | SPDP-PEG12-NHS ester | Broadpharm | MFCD13185005 | 912.070 | C39H65N3O17S2 | 95.000 | O=C(CCSSc1ccccn1)NCCOCCOCCOCCOCCOCCOCCOCCOCCOCCOCCOCCOCCC(=O)ON1C(=O)CCC1=O | 100mg | 229582557
SPDP-PEG12-NHS ester | Broadpharm | 2601437-72-1 | MFCD13185005 | 912.070 | C39H65N3O17S2 | 95.000 | O=C(CCSSc1ccccn1)NCCOCCOCCOCCOCCOCCOCCOCCOCCOCCOCCOCCOCCC(=O)ON1C(=O)CCC1=O | 100mg | 229582557
(=O)=O)c3ccc(cc3C2(C)CCCCCC(=O)NCCCNC(=O)OCCOCCN)S([O-])(=O)=O)N(CCCS(O)(=O)=O)c2ccc(cc12)S(O)(=O)=O | 5mg | 798871050](https://assets.fishersci.com/TFS-Assets/CCG/product-images/502472792.JPG-250.jpg)
eMolecules Amine-PEG-Fluor-647 TEA salts, MW 2,000 | Broadpharm |1046.250 | C44H63N5O16S4 | 95.000 | CC1(C)\C(=C/C=C/C=C/C2=[N+](CCCS(O)(=O)=O)c3ccc(cc3C2(C)CCCCCC(=O)NCCCNC(=O)OCCOCCN)S([O-])(=O)=O)N(CCCS(O)(=O)=O)c2ccc(cc12)S(O)(=O)=O | 5mg | 798871050
Amine-PEG-Fluor-647 TEA salts, MW 2,000 | Broadpharm |1046.250 | C44H63N5O16S4 | 95.000 | CC1(C)\C(=C/C=C/C=C/C2=[N+](CCCS(O)(=O)=O)c3ccc(cc3C2(C)CCCCCC(=O)NCCCNC(=O)OCCOCCN)S([O-])(=O)=O)N(CCCS(O)(=O)=O)c2ccc(cc12)S(O)(=O)=O | 5mg | 798871050
![eMolecules 2093197-98-7 | BDP FL-PEG5-acid | Broadpharm | MFCD30723280 | 583.440 | C27H40BF2N3O8 | 95.000 | CC1=CC(C)=[N+]2C1=Cc1ccc(CCC(=O)NCCOCCOCCOCCOCCOCCC(O)=O)n1[B-]2(F)F | 1mg | 340376963](https://assets.fishersci.com/TFS-Assets/CCG/product-images/502458130.PNG-250.jpg)
eMolecules 2093197-98-7 | BDP FL-PEG5-acid | Broadpharm | MFCD30723280 | 583.440 | C27H40BF2N3O8 | 95.000 | CC1=CC(C)=[N+]2C1=Cc1ccc(CCC(=O)NCCOCCOCCOCCOCCOCCC(O)=O)n1[B-]2(F)F | 1mg | 340376963
BDP FL-PEG5-acid | Broadpharm | 2093197-98-7 | MFCD30723280 | 583.440 | C27H40BF2N3O8 | 95.000 | CC1=CC(C)=[N+]2C1=Cc1ccc(CCC(=O)NCCOCCOCCOCCOCCOCCC(O)=O)n1[B-]2(F)F | 1mg | 340376963
Medchemexpress LLC Mal-PEG4-Val-Cit-PAB-MMAE | 98.0% | 1450.76 | 25 MG
Mal-PEG4-Val-Cit-PAB-MMAE is a drug-linker conjugate designed for Antibody-Drug Conjugate (ADC) research. It comprises a degradable ADC linker and a potent tubulin inhibitor.
- Contains a degradable ADC linker, Mal-PEG4-Val-Cit-PAB
- Contains a potent tubulin inhibitor, MMAE
eMolecules 1191064-81-9 | FMOC-NH-PEG9-CH2CH2COOH | MFCD28385470 | 1g
1-(5-Bromo-6-methoxy-pyridin-3-yl)-ethanone | Chemcia | 1256837-15-6 | MFCD18258545 | 230.061 | C8H8BrNO2 | 97.000 | COc1ncc(cc1Br)C(C)=O | 1g | 322910615
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![eMolecules Folate-PEG-amine, MW 2,000 | Broadpharm |527.542 | C23H29N9O6 | 0.000 | NCCOCCNC(=O)CCC(NC(=O)c1ccc(NCc2cnc3nc(N)[nH]c(=O)c3n2)cc1)C(O)=O | 50mg | 649281325](https://assets.fishersci.com/TFS-Assets/CCG/product-images/502475583.JPG-250.jpg)
eMolecules Folate-PEG-amine, MW 2,000 | Broadpharm |527.542 | C23H29N9O6 | 0.000 | NCCOCCNC(=O)CCC(NC(=O)c1ccc(NCc2cnc3nc(N)[nH]c(=O)c3n2)cc1)C(O)=O | 50mg | 649281325
Folate-PEG-amine, MW 2,000 | Broadpharm |527.542 | C23H29N9O6 | 0.000 | NCCOCCNC(=O)CCC(NC(=O)c1ccc(NCc2cnc3nc(N)[nH]c(=O)c3n2)cc1)C(O)=O | 50mg | 649281325
Cayman Chemical ANTIBODY DBCO-amIn 50mg
A copper-free click chemistry reagent; has been used in the synthesis of clickable fluorescent probes
eMolecules 1609651-90-2 | ChemScene | Alkyne-PEG4-maleimide | 100mg | 686120423 | CS-0118065 | MFCD22380740 | 382.413 | C18H26N2O7
Medchem Express | BAY 2416964 | 5mg | 527574132 | HY-135829 | 2242464-44-2 | 387.820 | C18H18ClN5O3
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eMolecules 1835759-82-4 | t-Boc-Aminooxy-PEG3-acid | Broadpharm | MFCD29052175 | 337.369 | C14H27NO8 | 97.000 | CC(C)(C)OC(=O)NOCCOCCOCCOCCC(O)=O | 100mg | 296213224
t-Boc-Aminooxy-PEG3-acid | Broadpharm | 1835759-82-4 | MFCD29052175 | 337.369 | C14H27NO8 | 97.000 | CC(C)(C)OC(=O)NOCCOCCOCCOCCC(O)=O | 100mg | 296213224