A Label-free Electrochemiluminescent Biosensor Of Glycogen Synthase Kinase-3 Beta For Investigation Of Alzheimer's Disease

Alzheimer's disease(AD)is a serious neurodegenerative disease,but there is no clinically definitive diagnosis currently.The high phosphorylation of ?-protein is one of the typical pathological changes,and glycogen synthase kinase-3 beta(GSK-3?)was a central kinase for ?-protein phosphorylation,and also directly linked to the increasement of A? production and deposition which would damage the synapses of AD patients.But in recent years,some people think solid data on the physiological and pathological aspects of GSK-3 in healthy human brain and in neurological diseases and dementia are rare and far apart.Therefore,the detection of this kinase is not only a potential choice for the prevention and treatment of AD,but also provides a new tactic to clarify the specific pathogenesis of AD.This paper reports a novel label-free electrochemiluminescent(ECL)biosensor for the detection of GSK-3?.The simpler and more feasible sensor was made with a two-step process.The sensory hosting matrix is a polymeric coordination layer of phosphorylated poly-vinyl with Zr4+ because of the formation of tile complex between them.The exterior Zr4+ ions can further combine with other two phosphates througn the coordination,here the GSK-3? catalyzes the phosphorylation of protein molecules.Thus,the biosensor can detect GSK-3? by using luminol as ECL probe.The ECL intensity on resultant sensor,under a direct immersion mode,is proportional to the concentration of GSK-3? and owned a linear response to its logarithm ranged from 0.5 ng L"1 to 91.5 ng L-1,with a detection limit of 0.0546 ng L-1.This biosensor exhibits excellent specificity,reproducibility and stability,while this method has simple preparation,low cost,and is suitable for disposable use.It showed important value for the clinic-chemistry for investigations of Alzheimer's disease(AD).