Jonathan Sayago

By Zhihui Yi and Jonathan Sayago

The impressive improvement in biomolecular detection has gone from simple chemical methods to sophisticated high throughput laboratory machines capable of accurately measuring the complex biological components and interactions. In the following chapter, we focus our attention on transistor‐based devices as an emerging platform for easy‐to‐use, portable amplified biodetection for preventive personalized medical applications and point‐of‐care testing. Electronic sensing devices comprise biosensors based on field‐effect transistors (bio‐FETs) and organic electrochemical transistors (OECTs). Transistor sensing devices can transduce electronic and ionic signals thereby creating an effective human‐machine communication channel. In this chapter, we survey the progress done on the development of transistor innovative concepts to examine biological processes, i.e., biosensors integrated with textiles, flexible substrates, and biocompatible materials. Electrochemical and field‐effect transistors can operate at low voltages possibly serving for highly sensitive, selective, and real‐time sensing devices. The exploration of biosensors integrates different disciplines such as organic electronics, biology, electrochemistry, and materials science.

Part of the book: Different Types of Field-Effect Transistors

By Irina Valitova, Zhihui Yi and Jonathan Sayago

Accurate, quantitative measurements of ionizing radiation, commonly employed in medical diagnostic and therapeutic applications are essential prerequisites to minimize exposure risks. Common examples of radiation detectors include ionization chambers, thermoluminescent dosimeters, and various semiconductor detectors. Semiconductor dosimeters such as p/n type silicon diodes and MOSFETs have found widespread adoption due to their high sensitivity and easy processing. A significant limitation of these devices, however, is their lack of tissue equivalence. The high atomic number (relative to soft tissue) of silicon causes these devices to over-respond to photon beams that include a significant low energy component, for example, 1–10 kV, due to an enhanced photoelectric interaction coefficient. Organic field effect transistors (OFETs) are capable of providing tissue equivalent response to ionizing radiation in order to monitor more accurately the risk of exposure in medical treatments. This chapter presents the possibility to use different types of OFETs as ionizing and X-ray radiation dosimeters in medical applications.

Part of the book: Integrated Circuits/Microchips