Plasmon resonance biosensor for interleukin-1 point-of-care determination: A tool for early periodontitis diagnosis

Among pro-inflammatory cytokines, Interleukin-1b is crucially involved in several inflammatory-based diseases and even cancer. Increased Interleukin-1b levels in oral fluids have been proposed as an early marker of periodontitis, a broadly diffused chronic inflammatory condition of periodontal-supporting tissues, leading eventually to tooth loss. We describe the development of a portable surface-plasmon-resonance-based optical fiber probe suitably coated with an anti-Interleukin-1b antibody monolayer. A piconanomolar linear range of determination was obtained in both buffer solution and saliva with a rapid (3 min) incubation and high selectivity in presence of interferents. Higher Interleukin-1b concentration in the saliva of a periodontitis patient compared to a healthy control was determined. These measurements were validated by an automated ELISA system. Our results sustain the potential applicability of the proposed SPR-POF as diagnostic point-of-care device for real-time monitoring of salivary Interleukin-1b, that can support early detection of oral inflammatory-based pathologies and rapid and timely therapeutic decisions.