Plasmonic optical fiber biosensor development for point-of-care detection of malondialdehyde as a biomarker of oxidative stress

• Published in: Free radical biology & medicine 2023-04, Vol.199, p.177-188
• Main Authors: Bencivenga, Debora, Arcadio, Francesco, Piccirillo, Angelantonio, Annunziata, Marco, Della Ragione, Fulvio, Cennamo, Nunzio, Borriello, Adriana, Zeni, Luigi, Guida, Luigi
• Format: Article
• Language: English
• Subjects: Biomarker; Biomarkers; Biosensing; Biosensing Techniques; Humans; Malondialdehyde; Optical Fibers; Oxidative Stress; Periodontitis; Point-of-Care Systems; Point-of-care tests; Redox homeostasis; Surface plasmon resonance
• ISSN: 0891-5849; 1873-4596
• DOI: 10.1016/j.freeradbiomed.2023.02.020

Numerous pieces of evidence demonstrate that oxidative stress impairs biological functions, speeds up aging, and has a role in a variety of human diseases, including systemic and oral inflammatory disorders, and even cancer. Therefore, technologies providing accurate measures of oxidative stress indicators or biomarkers appear essential in the identification/prevention of such diseases, and in their management. Particularly advantageous is the employement of point-of-care tests based on affordable and small biochips since they can quickly process biological samples and deliver results near the point of care for a prompt therapeutic intervention. Malondialdehyde (MDA) is a key byproduct of oxidative reaction and has been identified as an effective marker of oxidative stress. Herein, we describe the detection of MDA in buffer and in a complex matrix such as saliva, using a plasmonic optical fiber device combined with a highly selective anti-MDA antibody. The experimental results highlight the excellent performance of the proposed biosensor, as well as its ability to provide a low-cost point-of-care test (PoC-T) to be used in real life situations. We demonstrated that a single saliva dilution step and a short incubation time are required for the accurate detection of low concentrations of total MDA (free and conjugated). As a proof-of-concept of future biomedical applications, the method has been tested to determine MDA concentration in saliva of a periodontitis patient compared to that of a healthy control. The obtained findings represent the basis for developing PoC-Ts to be employed in monitoring oral diseases like periodontitis, oral cancers or systemic oxidative-stress associated pathologies. Conclusively, our study puts the ground for an oxidative stress biosensor widely-applicable to different scenarios. [Display omitted] •A portable surface plasmon resonance-based optical fiber biosensor is proposed to monitor MDA in biological fluids.•An anti-MDA antibody self-assembled monolayer (SAM) on a gold surface was utilized as probe.•No derivation strategies, described as potentially increasing MDA levels in vitro, were used for measurements.•The limit of free MDA detection was 14 pM in buffer solution.•Satisfactory recovery in complex matrix like saliva was obtained, with a limit of total MDA detection of 60 pM.