A pyrane based fluorescence probe for noninvasive prediction of cerebral β-amyloid fibrils

A potential fluorescence probe for in vivo detection of cerebral β-amyloid fibrils, (E)-2-(2-(2-(5-(dimethylamino)thiophen-2-yl)vinyl)-6-methyl-4H-pyran-4-ylidene)malononitrile (PT-1), was synthesized and evaluated. In experiments in vitro, PT-1 exhibited clear labeling of β-amyloid fibrils and significant fluorescence changes upon binding to aggregated β-amyloid fibrils. It also showed favorite kinetics in the brain, which is critical for cerebral imaging. In vivo fluorescence imaging with PT-1 and semi-quantitative analysis of the images further confirmed noninvasive visualization of cerebral β-amyloid fibrils in vivo and obvious distinction between APP/PS1 transgenic mice and wild-type controls. The results demonstrate the potential of PT-1 as a novel fluorescence probe for noninvasive prediction of cerebral β-amyloid fibrils.