Alzheimer disease (AD) is a severe neurodegenerative disease threating health of human being. Still, the treatment of AD is limited to conventional drug delivery pathway which failed to deliver an adequate amount of the drug in the brain. Intranasal drug administration pathway, given its proximity to the brain, provides a great opportunity for AD treatment. Also, olfactory dysfunction has been reported to be an early symptom of AD. Many researches have indicated olfactory bulb (OB) is the first region of the olfactory system to be damaged in AD. And olfactory bulb is where AD drugs must pass to get into the brain for intranasal delivery. Therefore, olfactory bulb biosensor based on MEA was established to monitor the effect of AD drugs in real-time, hopefully contributing to the intranasal administration of AD individual-based treatment.