Protein Modification Reagents
Medchemexpress LLC N-(2-(4-(3,5-dioxo-1,2,4-triazolidin-4-yl)-2-methoxyphenoxy)ethyl)-4,7,10,13-tetraoxahexadec-1-5-ynamide | 99.3% | 508.52 g/mol | C23H32N4O9 | 5 MG
PTAD-PEG4-alkyne is a cleavable four-unit polyethylene glycol (PEG) linker bearing an alkyne group for click chemistry and antibody-drug conjugate synthesis. It enables conjugation to azide-functionalized molecules via copper-catalyzed azide-alkyne cycloaddition and provides a hydrophilic, cleavable spacer for payload attachment.
- Contains terminal alkyne for CuAAC (click) conjugation.
- Four-unit PEG spacer provides hydrophilicity and cleavability for ADC applications.
- High purity (99.3%) and molecular weight approximately 508.52 g/mol.
- Available in small research pack sizes, for example 5 mg.
- Storage: powder at -20°C; in solvent: -80°C up to 6 months, -20°C up to 1 month.
Medchemexpress LLC Mal-PEG4-propargyl | 1262681-30-0 | 99.7% | 311.33 | 50 MG
Mal-PEG4-propargyl is a PEG-based PROTAC linker used in the synthesis of PROTACs. It acts as a click chemistry reagent, featuring an Alkyne group that allows it to participate in copper-catalyzed azide-alkyne cycloaddition (CuAAc) with molecules containing Azide groups. PROTACs are composed of two distinct ligands joined by a linker; one ligand targets an E3 ubiquitin ligase, while the other targets a specific protein, leveraging the intracellular ubiquitin-proteasome system for selective degradation of target proteins.
- PEG-based PROTAC linker
- Used in the synthesis of PROTACs
- Functions as a click chemistry reagent
- Contains an Alkyne group
- Enables copper-catalyzed azide-alkyne cycloaddition (CuAAc)
- Reacts with molecules possessing Azide groups
- Facilitates protein degradation through the ubiquitin-proteasome system
Medchemexpress LLC Dspe-peg-oh | 99.89% | 100 MG
DSPE-PEG-OH (MW 2000) is a hydroxyl-terminated PEGylated phospholipid. Its hydrophobic tail allows for the encapsulation and aggregation of other hydrophobic drugs, and its hydroxyl terminus is suitable for further reactions. DSPE-PEG-OH (MW 2000) can be used to prepare liposomes or lipid nanoparticles.
- Hydroxyl-terminated PEGylated phospholipid.
- Hydrophobic tail enables encapsulation and aggregation of other hydrophobic drugs.
- Hydroxyl terminus suitable for further reactions.
- Can be used to prepare liposomes or lipid nanoparticles.
Medchemexpress LLC Bis-PEG4-TFP ester | 1446282-42-3 | MFCD21363292 | 98.0% | 590.41 | C24H22F8O8 | 25 MG
Bis-PEG4-TFP ester is a bifunctional PEG-based linker bearing tetrafluorophenyl (TFP) activated esters at both ends, designed for conjugation to amine-containing ligands during PROTAC and bioconjugation synthesis. Supplied as a liquid in small research-scale quantities, it is intended for research use only and should be stored under recommended conditions to maintain stability.
- Provides bifunctional TFP-activated esters for efficient amide coupling.
- PEG4 spacer offers a flexible, hydrophilic linker with defined length.
- High purity suitable for laboratory research and synthesis.
- Liquid form facilitates accurate handling and aliquoting.
- Storage recommendations support extended stability when protected from light and moisture.
Medchemexpress LLC TCO-PEG2-amine | 2141981-87-3 | ≥97.0% | C15H28N2O4 | 50 MG
TCO-PEG2-amine is a PEG-based PROTAC linker. This compound is used in the synthesis of PROTACs.
- Purity of ≥97.0%
- Molecular formula C15H28N2O4
- Molecular weight 300.39
- Appears as a colorless to light yellow liquid
- Recommended storage at 4°C, protected from light
- Suitable for PROTAC synthesis
Medchemexpress LLC PTAD-PEG8-alkyne | 684.73 | 5 MG
PTAD-PEG8-alkyne is a cleavable ADC linker used in the synthesis of antibody-drug conjugates (ADCs).
- Used as a cleavable ADC linker
- Target: ADC linker
- Pathway: Antibody-drug conjugate/ADC related
- Storage: Pure form: -20°C for 3 years
- Storage: In solvent: -80°C for 6 months, -20°C for 1 month
Medchemexpress LLC Cyclooct-4-en-1-yl (2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethyl)carbamate | 1800507-93-0 | 95.0% | C17H32N2O5 | 10MG
TCO-PEG3-amine is a trans-cyclooctene (TCO)-functionalized PEG3 linker terminating in a primary amine, designed for bioconjugation and linker assembly in targeted degrader and chemical biology workflows. It combines a hydrophilic PEG spacer with a fast-reacting TCO handle for bioorthogonal labeling and a free amine for conventional coupling chemistries.
- Provides a trans-cyclooctene handle for rapid bioorthogonal click reactions.
- Contains a PEG3 spacer to improve solubility and reduce steric hindrance.
- Features a terminal primary amine for amide bond formation and conjugation.
- Suitable for PROTAC linker assembly, bioconjugation, and labeling applications.
- Offered as a high-purity research reagent with defined molecular properties.
eMolecules Combi-Blocks Acetylene-PEG4-biotin conjugate 250mg 415498461 QG-7572 95 000 1458576-00-5 MFCD22380755 457 590 C21H35N3O6S
Combi-Blocks Acetylene-PEG4-biotin conjugate 250mg 415498461 QG-7572 95 000 1458576-00-5 MFCD22380755 457 590 C21H35N3O6S
Medchemexpress LLC M-PEG4-PFP ester | 2952895-31-5 | 98.0% | 402.31 | 25 MG
M-PEG4-PFP ester is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs.
- Molecular weight: 402.31
- Formula: C16H19F5O6
- Appearance: Liquid
- Color: Colorless to light yellow
- Solubility in DMSO: ≥ 100 mg/mL (248.56 mM)
![eMolecules Broadpharm / Biotin-PEG4-STP Ester / 5mg / 795362059 / BP-40302 / / / [null] / 719.720 / C27H37F4N3O11S2](https://assets.fishersci.com/TFS-Assets/CCG/product-images/502466200.JPG-250.jpg)
eMolecules Broadpharm / Biotin-PEG4-STP Ester / 5mg / 795362059 / BP-40302 / / / [null] / 719.720 / C27H37F4N3O11S2
Broadpharm / Biotin-PEG4-STP Ester / 5mg / 795362059 / BP-40302 / / / [null] / 719.720 / C27H37F4N3O11S2
Medchemexpress LLC NHS-PEG2-SS-PEG2-NHS | 96.7% | 580.63 g/mol | C22H32N2O12S2 | 5 MG
NHS-PEG2-SS-PEG2-NHS is a cleavable four-unit polyethylene glycol (PEG) linker with N-hydroxysuccinimide (NHS) ester end groups and a disulfide (SS) cleavable junction, supplied for use in antibody-drug conjugate synthesis and other bioconjugation applications.
- Cleavable disulfide bond enables reductive release of payloads.
- Hydrophilic PEG spacer improves solubility and reduces aggregation.
- NHS ester end groups provide rapid amine coupling to proteins.
- Moderate molecular weight supports spacer function without excessive steric bulk.
- Available in small research sizes suitable for conjugation optimization.
![eMolecules Broadpharm / 14-(Amide-PEG4-ethylcarbamoyl)tridecanoic t-butyl ester / 100mg / 784455750 / BP-40053 / 95.000 / / [null] / 532.763 / C28H56N2O7](https://assets.fishersci.com/TFS-Assets/CCG/product-images/502473268.JPG-250.jpg)
eMolecules Broadpharm / 14-(Amide-PEG4-ethylcarbamoyl)tridecanoic t-butyl ester / 100mg / 784455750 / BP-40053 / 95.000 / / [null] / 532.763 / C28H56N2O7
Broadpharm / 14-(Amide-PEG4-ethylcarbamoyl)tridecanoic t-butyl ester / 100mg / 784455750 / BP-40053 / 95.000 / / [null] / 532.763 / C28H56N2O7
Medchemexpress LLC m-PEG20-alcohol 25mg
m-PEG20-alcohol is a PEG-based PROTAC linker that can be used in the synthesis of PROTACs[1]
Medchemexpress LLC Bromoacetamido-PEG4-NHS ester | 1260139-70-5 | 98.69% | C17H27BrN2O9 | 250 MG
Bromoacetamido-PEG4-NHS ester is a PEG-based PROTAC linker utilized in the synthesis of PROTACs. PROTACs consist of two distinct ligands joined by a linker; one ligand targets an E3 ubiquitin ligase, and the other targets the protein of interest. PROTACs function by leveraging the intracellular ubiquitin-proteasome system to selectively degrade target proteins.
- PROTAC linker
- Suitable for the synthesis of PROTACs
- Intended for research use only