A nano-biosensor for chair side monitoring of salivary MMP-8 in periodontitis

Objectives: Chair-side monitoring of inflammatory mediators of periodontitis can provide immediate information about disease activity, which can inform patient management. For this purpose, we aimed to develop a novel prototype device, which can effectively measure salivary MMP-8, an established biomarker of periodontitis.
Methods: Surface acoustic wave (SAW) biosensor chips were coated with MMP-8-specific capture antibody. The detection of soluble MMP8 in saliva samples was carried out by application of the sample to the biosensor chips followed by signal enhancement with a second MMP-8 specific antibody. The analytical performance of the SAW biosensor was compared to standard ELISA (Quantikine, R&D Systems) using unstimulated saliva samples obtained from patients with untreated periodontitis (N=58), gingivitis (N=54) and periodontally healthy volunteers (N=65).
Results: In agreement with the published literature, levels of salivary MMP-8 detected using both analytical approaches were significantly higher in periodontitis as compared to gingivitis (p< 0.001) and healthy controls (p< 0.001). Receiver operator characteristic analysis for distinguishing periodontitis from health revealed an almost identical performance (area under curve values: ELISA 0.93; SAW 0.89). The assay time for our prototype device is ~20 minutes.
Conclusions: The prototype SAW biosensor represents a promising development towards effective chair side monitoring of periodontitis. Further developments will focus on the refinement and clinical efficacy of the novel biosensors.