Gd.1

Gd.1 is a dual-modal magnetic resonance (MR) and fluorescent zinc-sensing probe developed for the in vivo imaging of pancreatic beta-cell mass and function. Chemically, it consists of a gadolinium(III) complex of a DO3A (1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid) macrocycle conjugated to an amidoquinoline (AQA) zinc-sensing fluorophore. Upon binding to zinc ions (Zn2+), which are highly concentrated in the secretory granules of pancreatic beta cells, Gd.1 undergoes a ratiometric fluorescent Stokes shift from 410 nm to 500 nm and exhibits an increase in longitudinal relaxivity (r1) from 4.2 to 4.9 mM-1 s-1 (and up to 6.6 mM-1 s-1 at 9.4 T). This dual-modal capability enables high-resolution anatomical MRI combined with sensitive optical detection of zinc-rich secretory granules, offering a potential diagnostic tool for monitoring beta-cell mass changes in diabetes.

Other names

Gd-DO3A-AQAGd-DO-3A-AQAGd-DO 3A-AQAGd.1(AQA)gadolinium-DO3A-AQA complexgadolinium-DO-3A-AQA complexgadolinium-DO 3A-AQA complex