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dPEG®₄-SATA (S-acetyl-dPEG®₄-NHS ester) (QBD-10181)


dPEG®4-SATA, product number QBD-10181, is a hydrophilic, water-soluble version of the highly popular thiolation and crosslinking reagent known as SATA. Using straightforward, easy reactions, this reagent can be used to thiolate or crosslink biomolecules.


dPEG®4-SATA, also known as S-acetyl-dPEG®4-NHS ester, product number QBD-10181, is one of Quanta BioDesign’s versions of the widely popular thiolation reagent N-succinimidyl-S-acetylthioacetate (SATA). The acetyl-protected thiol is separated from the N-hydroxysuccinimidyl (NHS) ester by an amphiphilic, discrete polyethylene glycol (dPEG®) spacer. The dPEG® spacer adds water solubility to the product.

Thiolation is the process of adding a sulfhydryl group to a molecule. Bioconjugation frequently employs thiolation because the reactions to install thiol groups on molecules or to react molecules with sulfhydryl groups are simple and often chemoselective.

The widely popular SATA reagent thiolates molecules with available amines via the NHS ester. Removal of the acetyl protecting group from the sulfhydryl permits crosslinking between the SATA-modified compound and a target molecule of interest that contains a thiol-reactive group, such as maleimide. Unfortunately, SATA is hydrophobic. Consequently, before use, SATA must be dissolved in a dry, water-miscible organic solvent.

Vector Laboratories’ dPEG®4-SATA inserts a single molecular weight tetraethylene glycol (dPEG®4) spacer between the protected thiol and the NHS ester. The dPEG® spacer imparts water solubility to the molecule, allowing dPEG®4-SATA to be dissolved and reacted in water without the need for an organic solvent. Also, the dPEG®4 spacer adds hydrodynamic volume to the molecule to which it is conjugated.

Increasing the hydrodynamic volume reduces aggregation and precipitation of proteins conjugated to dPEG®4-SATA. Hydroxylamine hydrochloride (CAS number 5470-11-1) easily removes the acetyl protecting group, exposing the sulfhydryl moiety for further reaction. Any application that can be carried out with a traditional, non-PEGylated SATA reagent can be carried out with our SATA containing a dPEG® spacer.


Unit Size100 mg, 1000 mg
Molecular Weight421.46; single compound
Chemical formulaC₁₇H₂₇NO₉S
Purity> 98%
SpacersdPEG® Spacer is 16 atoms and 18.3 Å
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, Acetontrile, DMAC or DMSO.
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.


  1. Greg T. Hermanson, Bioconjugate Techniques, 2nd Edition, Elsevier Inc., Burlington, MA 01803, April, 2008 (ISBN-13: 978-0-12-370501-3; ISBN-10: 0-12-370501-0). References to SATA which can be directly applied to the dPEG® pegylation versions: a) general description and use, p 71; b) modification of antibodies, pp 759; c)modification of amines on nucleus and DNA probes, p. 984 and d) modification of enzymes, avidin and streptavidin with pp. 90, 909 and 919.
  2. 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.
  3. Elongated plant virus-based nanoparticles for enhanced delivery of thrombolytic therapies. Andrzej Stanislaw Pitek, Yunmei Wang, Sahil Gulati, Huiyun Gao, Phoebe L Stewart, Daniel I. Simon, and Nicole F Steinmetz. Molecular Pharmaceutics. 2017, pp 1-9. September 7, 2017. DOI: 10.1021/acs.molpharmaceut.7b00559.
  4. Biodegradable Polydisulfide Dendrimer Nanoclusters as MRI Contrast Agents. Ching-Hui Huang, Kido Nwe, Ajlan Al Zaki, Martin W. Brechbiel, and Andrew Tsourkas. ACS Nano. 2012, 6 (11) pp 9416–9424. October 25, 2012. DOI: 10.1021/nn304160p.
  5. Silica-Shelled Single Quantum Dot Micelles as Imaging Probes with Dual or Multimodality. Rumiana Bakalova, Zhivko Zhelev, Ichio Aoki, Hideki Ohba, Yusuke Imai, and Iwao Kanno. Anal. Chem. 2006, 78 (16) pp 5925–5932. July 14, 2006. DOI: 10.1021/ac060412b.
  6. Robust IgG responses to nanograms of antigen using a biomimetic lipid-coated particle vaccine. Anna Bershteyn, Melissa C. Hanson, Monica P. Crespo, James J. Moon, Adrienne V. Li, Heikyung Suh, Darrell J. Irvine. Journal of Controlled Release. 2011, 157 (3) pp 354-365. July 24, 2011. DOI: 10.1016/j.jconrel.2011.07.029.
  7. Synthesis and Function of Bioactive, Block Copolymer Surfactant Constructs
    as Relevant to the Preparation of Anticoagulant and Antibacterial Medical Implant Surfaces. Pranav R. Joshi. Doctor of Philosophy in Chemical Engineering. 2006, November 17, 2006.
  8. Immobilization of His-tagged endoglucanase on gold via various Ni-NTA self-assembled monolayers and its hydrolytic activity. Nakamura I, Makino A, Ohmae M, Kimura S. Macromolecular Bioscience. 2010, 10 (10) pp1265-1272. October 8, 2010. DOI: 10.1002/mabi.201000189.
  9. Array-based fluorescence assay for serine/threonine kinases using specific chemical reaction. Shoji Akita, Naoki Umezawa, Nobuki Kato, Tsunehiko Higuchi. Bioorganic & Medicinal Chemistry. 2008, 16 (16) pp 7788-94. July 1, 2008. DOI: 10.1016/j.bmc.2008.07.007.
  10. Serum albumin ‘camouflage’ of plant virus based nanoparticles prevents their antibody recognition and enhances pharmacokinetics. Andrzej S. Pitek, Slater A. Jameson, Frank A. Veliz, Sourabh Shukla, and Nicole F. Steinmetz. Biomaterials. 2016, 89 pp 89-97, February 23, 2016. DOI: 10.1016/j.biomaterials.2016.02.032.
  11. Mapping of Molecular Structure of the Nanoscale Surface in Bio-nanoparticles. Luciana M Herda, Delyan R Hristov, Maria Cristina Lo Giudice, Ester Polo, and Kenneth A Dawson. Journal of the American Chemical Society. 2017. 139(1), 111-114. DOI: 10.1021/jacs.6b12297.

Applicable patents and legal notices are available at legal notices.

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