Fluorescein-PEG-CH2CH2COOH

Fluorescein-poly(ethylene glycol)-carboxylic acid (Fluorescein-PEG-COOH) is a functional dye combining a fluorescein chromophore, a defined-length PEG spacer, and a carboxyl conjugation terminus. The PEG spacer is available in discrete chain lengths with different degrees of polymerization. The carboxyl group can be activated for amide coupling with primary-amine-containing molecules, retaining a handle for subsequent ligand or carrier attachment. The PEG spacer separates the chromophore from the target attachment site. Chain length can be selected in relation to labeling position, local environment, and conjugate dispersion.

Customization available.