| Abstract: | Solution‐processable organic semiconductors have been investigated not only for flexible and large‐area electronics but also in the field of biotechnology. In this paper, we report the design and fabrication of biosensors based on completely organic thin‐film transistors (OTFTs). The active material of the OTFTs is poly(9,9‐dioctylfluorene‐co‐bithiophene) (F8T2) polymer functionalized with biotin hydrazide. The relationship between the chemoresistive change and the binding of avidin‐biotin moieties in the polymer is observed in the output and on/off characteristics of the OTFTs. The exposure of the OTFTs to avidin causes a lowering of ID at VD = ‐40 V and VG = ‐40 V of nearly five orders of magnitude. |
