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Thiol-dPEG®₄-acid (QBD-10247)



Thiol-dPEG®4-acid, product number QBD-10247, contains a short, monodisperse polyethylene glycol (PEG) linker functionalized with a sulfhydryl group on one end and a propionic acid moiety on the other.The sulfhydryl forms dative bonds with gold and silver and reacts with thiol-reactive functional groups such as maleimide, bromoacetyl, SPDP, and thiol. The carboxylic acid end of the molecule couples to free amines using EDC or any suitable carbodiimide. An acylating agent such as N-hydroxysuccinimide (NHS) or 2,3,5,6-tetrafluorophenol (TFP) can enhance coupling efficiency. The carboxylate must react after the sulfhydryl conjugation.

Thiol-dPEG®4-acid forms dative bonds with gold surfaces and provides a non-immunogenic, hydrophilic spacer between the gold coat and the environment surrounding the gold. The terminal carboxylic acid can be left unmodified, or it can react with amines to crosslink other molecules to the gold.

In published scientific literature, Thiol-dPEG®4-acid in a mixed monolayer has prevented opsonization of gold nanoparticles. Other published uses for this product include coating nanoparticles, coating gold electrodes used in ion channel recording, developing aptamer-based sensors, and developing a chemical detector with nanometer-scale spatial resolution.


Unit Size100 mg, 1000 mg
Molecular Weight282.35; single compound
Chemical formulaC₁₁H₂₂O₆S
Purity> 98%
SpacersdPEG® Spacer is 16 atoms and 18.3 Å
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, Acetonitrile, DMAC, DMSO or moderate solubility in water.
Storage and handling-20°C; Always let come to room temperature before opening; be careful to limit exposure to moisture and restore under an inert atmosphere; stock solutions can be prepared with dry solvent and kept for several days (freeze when not in use). dPEG® pegylation compounds are generally hygroscopic and should be treated as such. This will be less noticeable with liquids, but the solids will become tacky and difficult to manipulate, if care is not taken to minimize air exposure.


Greg T. Hermanson, Bioconjugate Techniques, 3rd Edition, Elsevier, Waltham, MA 02451, 2013, ISBN 978-0-12-382239-0; See Chapter 18, Discrete PEG Reagents, pp. 787-821, for a full overview of the dPEG® products.

Short-Chain PEG Mixed Monolayer Protected Gold Clusters Increase Clearance and Red Blood Cell Counts. Carrie A. Simpson, Amanda C. Agrawal, Andrzej Balinski, Kellen M. Harkness, and David E. Cliffel. ACS Nano. 2011, 5 (5), pp 3577-3584. April 7, 2011. DOI: 10.1021/nn103148x.

CdSe nano-particles coated with thiol-terminated oligo(ethylene oxide) for protein targeting reagent. Yukari Ito and Hiromori Tsutsumi. NSTI-Nanotech. 2009, 2. 2009.

A Simple Method for Ion Channel Recordings Using Fine Gold Electrode. Daichi Okuno, Minako Hirano, Hiroaki Yokota, Yukiko Onishi, Junya Ichinose, and Toru Ide. Analytical Sciences. 2016, 32 (12) pp 1353-1357. December 10, 2016.

The combination of computational and biosensing technologies for selecting aptamer against prostate specific antigen. Pi-Chou Hsieh, Hui-Ting Lin, Wen-Yih Chen, Jeffrey J.P. Tsai, and Wen-Pin hu. 2017, pp 1-36.

Spatially Resolved Chemical Detection with a Nanoneedle-Probe-Supported Biological Nanopore. Kan Shoji, Ryuji Kawano, and Ryan J. White. ACS Nano, 2019, 13 (2), pp 2606–2614. February 6, 2019. DOI: 10.1021/acsnano.8b09667.

Milk protein-shelled gold nanoparticles with gastrointestinally active absorption for aurotherapy to brain tumor. Hyung Shik Kim, Seung JaeLee, Dong Yun Lee. Bioactive Materials. 2022, Volume 8. 02/2022. DOI: 10.1016/j.bioactmat.2021.06.026

A novel therapeutic strategy of multimodal nanoconjugates for state-of-the-art brain tumor phototherapy. Hyung Shik Kim, Minwook Seo, Tae-Eun Park, and Dong Yun Lee. SpringerLink. 2022. January 4, 2022.

Applicable patents and legal notices are available at legal notices.

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