DOTA-tris(TBE)-amido-dPEG®₂₄-TFP ester (QBD-11158)

Description

DOTA-tris(TBE)-amido-dPEG®24-TFP ester, product number QBD-11158, contains a DOTA-tris(TBE) group conjugated to a long (76 atoms, 88.8 Å), discrete polyethylene glycol (dPEG®) spacer and functionalized with 2,3,5,6-tetrafluorophenyl (TFP) ester. The TFP ester reacts specifically and efficiently with amines at an optimal pH range of 7.5 – 8.0.

The macrocycle 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) is a popular, effective bifunctional chelator used in radiopharmaceutical applications (radioimaging, radiotherapeutics) that require trivalent radioisotopes of yttrium or lanthanides. This form of DOTA has the four acetate groups protected with tert-butyl esters (TBE) and is not an effective chelator. However, it is useful in situations where the DOTA needs to be incorporated into the molecule at an early stage of development. The DOTA moiety becomes an effective chelator after the removal of the TBE protecting groups.

The long, amphiphilic, flexible dPEG® linker between the DOTA and the TFP ester moieties increases the hydrodynamic volume and water solubility of conjugate molecules. The increased hydrodynamic volume can act to reduce renal clearance of the conjugate, thereby increasing serum half-life and reducing the dosage of the conjugate required for efficacy. Moreover, dPEG® is non-immunogenic, and its large hydrodynamic volume helps reduce the immunogenicity of conjugated molecules.

Specifications

Documents

References

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). Specifically see pp. 726-729 in his Chapter 18 on discrete PEG compounds for pegylation applications.

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.