Aptamer Technology in the Detection of Salivary Biomarkers

Saliva is a crucial bodily fluid that protects the oral cavity from infections. The composition of saliva also changes dynamically depending on conditions such as illness, stress, and diet. Thus, the organic substances in saliva, particularly enzymes, proteins, and hormones, reflect overall health status and are increasingly valued as non-invasive diagnostic tools. Aptamers, which are short single-stranded DNA or RNA molecules with high affinity and specificity, have gained attention as novel biomarker detection tools. This study explores the feasibility of employing aptamers as an innovative diagnostic technique for detecting salivary biomarkers. Specifically, we discuss the development and application of aptamers tailored to detect key salivary biomarkers, such as salivary alpha-amylase, secretory immunoglobulin A (sIgA), human beta-defensin, C-reactive protein, and lactate dehydrogenase. Our group used base-appended bases to achieve high affinity and stability against targets. For instance, cortisol and sIgA in saliva are useful for assessing chronic stress and fatigue, thereby enabling objective evaluations of diseases. Enhanced techniques for measuring salivary biomarkers promise non-invasive and cost-effective diagnostic methods that can significantly contribute to early infection detection, chronic disease monitoring, and psychological stress assessment. This review underscores the extensive applicability of salivary biomarkers and provides critical insights that could improve future public health and medical care quality.