MAL-dPEG®₁₂-Tris(-dPEG®₂₄-acid)₃

MAL-dPEG®12-Tris(-dPEG®24-acid)3, product number QBD-11451, is a thiol- and amine-reactive, four-arm, monodispersed PEG with one arm shorter than the other three. MAL-dPEG®12-Tris(-dPEG®24-acid)3 is a monodispersed branched PEG compound built around a tris core. From the maleimide olefin to carbonyl carbon immediately before the tris core is 46 atoms. From the tris core to the carbonyl carbon on each branch is 83 atoms. The total linker length is 129 atoms. The maleimido group that terminates the short arm of this product reacts with sulfhydryl groups to form thioether bonds. It conjugates directly to target biomolecules.

This product is useful for charge modulation and elimination of renal clearance in drug delivery and imaging applications, among others. The dPEG® spacer length is from the maleimide olefin to the carbonyl carbon on each of the three long arms. The terminal carboxylic acid groups can be modified with various functional or reactive groups (e.g., NHS, TFP esters) or used as-is for charge modulation. In a peer-reviewed scientific publication, this product was shown to alter the biodistribution of the conjugate when used as a charge modulator on the antibody CC49, leading to improved microPET/CT imaging in mice.