SPR chip could provide early warning of Alzheimer’s disease

They are hoping to make a handheld or a small desktop device using surface plasmon resonance (SPR) — a relatively new technology — coupled with high-sensitivity complementary metal-oxide semiconductor (CMOS) imaging.

While diagnostic chips are starting to find their way into the clinic for certain applications, other conditions present a significant challenge, as project collaborator Prof Mike Somekh, an optical engineer at Nottingham University, explained.

‘With some diseases, there are single markers or chemicals that will actually give you a good indication of the diagnosis.

‘But a lot of other diseases such as Alzheimer’s and other neurodegenerative conditions are represented by a pattern of markers, so you have to see how they are interrelated to each other to get a good, accurate diagnosis. That then imposes a constraint on the engineer to develop a platform with multiple sites for analysis.’ 

With this in mind, Somekh turned to SPR — a complex process that essentially measures the adsorption of two molecules based on their evanescent wave refractive index.