“…Furthermore, some other optical imaging platforms such as chemiluminescence, tissue-auto-fluorescence, brush biopsy, optical coherence, and toluidine blue staining are utilized for early-stage screening of oral cancer biomarkers [121,122]. Moreover, the major challenges of the early diagnosis are the presence of low quantities of biomarkers in a clinical sample, which is hard to diagnose, and quantify and predict the clinical stage [3,123]. Among these diagnostic platforms, the electrochemical biosensors for the diagnosis of oral cancer biomarkers have been widely used because these are robust, user-friendly, easy to miniaturize, and offer wider detection limits even when a little volume of analytes are present.…”