Abbreviations: Iot, internet of things; ELISA, enzyme-linked immuno sorbent assay; WB, western blot; IHC, immunohistochemistry; ICC, immunocytochemistry; FACS, fluorescence-activated cell sorting; IP, immuno precipitation; ELISPOT, enzyme-linked immuno spot; PSA, prostate specific antigen; IDEs, interdigitated electrodes; HPV, human papilloma virus IntroductionBiosensors have been mostly used in the food industry, medical and biological fields, among others, where physical and chemical sensors cannot accurately measure all variables. Biosensors are usually comprised by a biological recognition element and a transducer.1,2 Among the different commercial biosensors, the most common recognition elements are DNA, 3 enzymes, 4 aptamers 5,6 and antibodies.7,8 DNA-based biosensors detect specific analytes by their cleavage and ligation to a functionalized DNA strand.9 Enzymatic biosensors immobilize an enzyme to an electrode to facilitate the transport of electrons from the enzyme to the electrode, produced by specific reactions at the active site of the enzyme.2 Aptamers are chemically synthesized oligonucleotides 10 that provide high specificity and sensitivity towards a specific target. Antibody-based biosensors recognize a specific antigen from the immobilization of a monoclonal or polyclonal antibody.8 In general, transducers vary according to the end user towards which the sensor is thought. Among others, transducers include electrochemical responses, mass changes, optical absorption or transmission, and thermal readings. During the last decades, several immunoassay techniques have appeared as a response to the need of having specific and sensitive tests for antigen recognition. The methods by which the recognition is perform varies from one to another, but the presence of at least one recognition antibody remains as a constant. Among others, the most common immune tests used in laboratories and medical facilities are the enzyme-linked immuno sorbent assay (ELISA), western blot (WB), immunohistochemistry (IHC), immunocytochemistry (ICC), fluorescence-activated cell sorting (FACS), immuno precipitation (IP), and enzyme-linked immuno spot (ELISPOT). Figure 1 shows a general diagram of these immunoassays.ELISA is a widely used technique for the recognition of antibodies' antigens within a sample by means of the biochemical recognition of an enzyme.11 In this technique, specific antibodies are conjugated to an enzyme that catalyzes a colorimetric molecule. Spectrophotometric measurements are used to determine the antigen concentration in the sample. ELISA tests can be performed in a qualitative way, in which the results are positive or negative by statistical methods; or quantitative, in which a standard curve from spectrophotometric measurements can be used to quantify the concentration of the antigen. 12WB is a technique for the detection of specific proteins in a sample through the electrophoretic transfer from a separating gel to a blotting matrix.13 WB uses available monoclonal or polyclonal antibodies for the d...