Smartphone based, portable optical biosensor utilizing surface plasmon resonance

A portable low cost biosensor suited for future medical diagnostic application is presented. The device comprises a custom designed scaffold, a disposable polymeric chip for surface plasmon resonance (SPR) sensing, and a smartphone. This commercial telecommunication device provides both, the optical illumination required for triggering of the SPR phenomenon and established by its active-matrix of organic light-emitting diodes (i.e., the smartphone display), whereas optical detection is obtained by means of its 1.9 Mpx CMOS image sensor that serves as the front camera. This concept does not require any additional optical device, except the SPR-chip itself and mechanical scaffold. The so-called angular interrogation mode has been employed for detection of the SPR feature. Employing appropriate data extraction algorithms, the sensitivity of the instrument approaches 10^-5 RIU. This value compares well with existing laboratory style SPR-instruments, confirming feasibility of this technical approach.