SENSOR AND SCREENING METHODS

The contents of the course are an overview of the main chemical sensors and their mechanisms of signal transduction. Are also addressed and depth aspects concerning the materials used as substrates for the development of sensors, the theoretical principles on which their working principle is based, and the methods used for their characterization.
The course is articulated into the following points:
-Definitions, characterization, quality parameters of the sensors.
-Transduction mechanisms.
-Potentiometric Sensors: Basic thermodynamics of electrochemical interphase potentials; ion-selective electrodes based on solid and liquid membranes; ionic receptors and ionophores, calibration procedures and assessment of quality parameters. Practical examples: automatic analyzers of electrolytes and gases dissolved in the blood samples; glass electrode for pH measurement, "Lambda" probe for the combustion control in the engines and for the management of the operation of catalytic converters.
-ISFET and MOSFET Sensors: Retrieve on the properties of semiconductors; “n-p" junctions; diodes and photodiodes; principle of operation of the field effect transistors (FET); combination of FET with ion-selective membranes (ISFET) and with films of metal mixed oxides ( MOSFET).

-Amperometric Sensors: Elements of electrodic thermodynamics and kinetics, mechanisms for mass transport and electronic transfer; reversibility of a response; Butler-Volmer equation and its graphical representation; instrumentation; electrodes modified with composites and nanocomposites active materials; conducting polymers and processes of modification of the electrode surface; miniaturization of electrodes and instrumentation, "screen printed" electrodes; applications in environmental, food and clinical samples
-Biosensors: Properties of bioreceptors as antibodies, enzymes and conjugates haptens; operating principle of competitive and non-competitive immunosensors; immobilization of bioreceptors of nanomaterials for the production of nanobiocomposite substrates; redox mediators, applications in clinical, environmental and food samples.
-Screening Techniques: General Principles; difference between methods of analysis and screening; immunochemical and immunoenzymatic assays, working principle of the "ELISA" kits (Enzyme Linked Immunosorbent Assay) "Lateral flow" ELISA test on disposable strips; applications in clinical field; examples; clinical analyses, determination of antibodies and biomarkers related to disease in blood samples, pregnancy and ovulation tests etc.