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Lipoamido-dPEG®₈-acid (QBD-10807)



Lipoamido-dPEG®8-acid, product number QBD-10806, is a single molecular weight, discrete PEG (dPEG®) surface modification reagent for metal surfaces, especially gold and silver. The hydrophilic dPEG®8 spacer is 36 atoms (41.2 Å) long. The lipoamide moiety rapidly forms stable dative bonds with gold or silver. Using a carbodiimide such as EDC and an acylating agent such N-hydroxysuccinimide (NHS), the propionic acid group will react with free amines to form amide bonds. The water-soluble, non-immunogenic dPEG® spacer adds hydrodynamic volume to conjugates made with this product. For circulating nanoparticles, the increased hydrodynamic volume reduces or eliminates opsonization and facilitates a longer circulation time in vivo.

Lipoic acid, also known as thioctic acid and alpha-lipoic acid (ALA), is an organosulfur compound used by cells as an essential cofactor. The sulfur atoms at positions C6 and C8 form a disulfide bond in a five (5)-membered ring. Like other thiol products, lipoic acid readily forms dative bonds with gold, silver, and other metals. Because two dative bonds form for each molecule of lipoic acid, the thiol-metal dative bond is more stable than dative bonds formed with compounds containing one free thiol atom. Lipoic acid exists typically in an oxidized (closed ring) state. It is readily reduced to an open ring state called dihydrolipoic acid (DHLA) using tris(2-carboxyethyl)phosphine (TCEP) or other reducing agents.


Unit Size100mg, 1000mg
Molecular Weight629.82; single compound
Chemical formulaC₂₇H₅₁NO₁₁S₂
Purity> 98%
SpacersdPEG® Spacer is 36 atoms and 41.2 Å
Typical solubility properties (for additional information contact Customer Support)Methylene chloride, DMAC, DMSO and limited solubility in acetonitrile.
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, 2nd Edition, Elsevier Inc., Burlington, MA 01803, April, 2008 (ISBN-13: 978-0-12-370501-3; ISBN-10: 0-12-370501-0), pp 188-190, 458-497, 924-935.

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.

Site-Specific Conjugation of Antibody on Gold Nanoparticle Surface for One-Step Diagnosis of Prostate Specific Antigen with Dynamic Light Scattering. Nur Mustafaoglu, Tanyel Kiziltepe, and Basar Bilgicer. Nanoscale. 2017, pp 1-32. May 18, 2017. DOI: 10.1039/C7NR03096G.

Single-wavelength-excited flurogenic nanoprobe for accurate realtime ratiometric analysis of broad pH fluctuations in mitophagy. Xin Zhang, Juan Chen, Jiwen Hu, Anna du Rietz, Xiongyu Wu, Ruilong Zhang, Zhongping Zhang, Kajsa Uvdal & Zhangjun Hu. SpringerLink. 2022. May 11, 2022.

Applicable patents and legal notices are available at legal notices.

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