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Phthalimidooxy-dPEG®4-NHS ester

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Empirical Formula (Hill Notation):
Molecular Weight:
MDL number:
PubChem Substance ID:




solid or viscous liquid

reaction suitability

reactivity: amine reactive
reagent type: cross-linking reagent
reactivity: thiol reactive

functional group

NHS ester

polymer architecture

shape: linear
functionality: heterobifunctional

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Features and Benefits

Phthalimidooxy-dPEG®4-NHS ester allows introduction of an oxyamine function onto a target molecule for cross-linking proteins or for creating stable conjugates with the target molecule. The oxyamine function is protected by a phthalimido protecting group on one end of the spacer arm, and the spacer is installed on the target molecule with the amine-reactive N-hydroxysuccinimide (NHS) group on the other end of the spacer. The single molecular weight dPEG® spacers have precise length for spatial control. They are hydrophilic and non-immunogenic. The dPEG® spacers improve water solubility and reduce aggregation and precipitation of proteins. The phthalimido protecting group can be removed using hydrazine. The oxyamine group exposed after deprotection can be reacted with an aldehyde- or ketone-containing molecule to form an oxime bond linking the two molecules. These reagents can be used with any protein, peptide, or small molecule that has a free amine.

Legal Information

Products Protected under U.S. Patents # 7,888,536 B2
dPEG is a registered trademark of Quanta BioDesign

Storage Class

11 - Combustible Solids




Not applicable


Not applicable

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