SPDP-PEG24-acid
Cat No.: BP-501739
4.5 
SPDP-PEG24-acid is a heterobifunctional polyethylene glycol (PEG) linker bearing an acid-terminated PEG chain and a pyridyl disulfide (SPDP) reactive group. Structurally, it combines a flexible, hydrophilic PEG spacer with a disulfide electrophile that can undergo thiol–disulfide exchange to form a stable thioether linkage after reaction with primary amines or engineered cysteines, depending on the conjugation strategy used. In PROTAC and targeted protein degradation workflows, this linker is used to spatially separate the binding ligand and the E3-recruiting module, improving effective reach and reducing steric interference at the ternary complex interface. The PEG chain length and terminal carboxylate support aqueous solubility and enable subsequent coupling handles (e.g., amide formation) for assembling multi-component degraders. Overall, it provides a practical, experimentally validated platform for constructing degraders with tunable geometry and robust conjugation chemistry.
Assurance
Delivery
Support
* For research and manufacturing use only. Not for human or clinical use.
| Size | Price | Stock | Quantity |
|---|---|---|---|
| -- | $-- | In stock |
Looking for different specifications? Click to request a custom quote!
Capabilities & Facilities
- Comprehensive PROTAC Platform
- Scientific Expertise & Technical Support
- Custom Synthesis & Design Service
- Extensive Product Coverage
- Cutting-Edge Innovation
- Fast Delivery & Global Support
- 24/7 customer service
- 100% quality assurance
Popular Publications Citing BOC Sciences Products
SPDP-PEG24-acid is a PEG-based heterobifunctional linker designed for constructing PROTACs and related targeted degradation conjugates through thiol-reactive and amine-reactive coupling strategies. Its flexible poly(ethylene glycol) segment supports favorable linker solvation and spacing, which can improve conjugate accessibility and reduce steric constraints during target engagement. The subsequent sections describe its structural features and practical reactivity considerations for assembly of degraders.
Structure: The linker contains a PEG chain terminating in a carboxylic acid handle, providing hydrophilicity and a polar, flexible spacer. It incorporates an activated disulfide-containing motif typical of SPDP-type chemistry, enabling site-specific conjugation via thiol exchange while preserving the PEG backbone’s conformational flexibility.
Reactivity: For PROTAC assembly, the SPDP-derived disulfide is commonly reacted with primary thiols under mild, aqueous-compatible conditions to form a new disulfide-linked conjugate via thiol–disulfide exchange. The carboxylic acid can be used for subsequent amide coupling or other carboxyl-derivatization steps using standard peptide-coupling chemistries. Typical workflows employ buffered aqueous media with controlled pH and inert atmosphere when disulfide stability is critical.
* Our calculator is based on the following equation:
Concentration (start) x Volume (start) = Concentration (final) x Volume (final)
It is commonly abbreviated as: C1V1 = C2V2
Related Product Recommendations
Please contact us with any specific requirements and we will get back to you as soon as possible.
