Oleyl group-functionalized insulating gate transistors for measuring extracellular pH of floating cells. Issue 1 (1st January 2016)

• Record Type: Journal Article
• Authors: Imaizumi, Yuki; Goda, Tatsuro; Toya, Yutaro; Matsumoto, Akira; Miyahara, Yuji
• Is Part Of: Science and technology of advanced materials. Volume 17:Issue 1(2016)
• Page Start: 337
• Page End: 345
• Publication Date: 2016-01-01
• Subjects: Ion-sensitive field-effect transistors -- self-assembled monolayer -- biocompatible anchor for cell membrane -- T lymphocytes -- hemolysis -- plasma membrane injury; 30 Bio-inspired and biomedical materials -- 101 Self-assembly/Self-organized materials -- 201 Electronics/Semiconductor/TCOs -- 208 Sensors and actuators -- 212 Surface and interfaces -- 502 Electron spectroscopy; Materials -- Technological innovations -- Periodicals; 620.112
• DOI: 10.1080/14686996.2016.1198217
• Languages: English
• ISSNs: 1468-6996

Abstract

Abstract: The extracellular ionic microenvironment has a close relationship to biological activities such as by cellular respiration, cancer development, and immune response. A system composed of ion-sensitive field-effect transistors (ISFET), cells, and program-controlled fluidics has enabled the acquisition of real-time information about the integrity of the cell membrane via pH measurement. Here we aimed to extend this system toward floating cells such as T lymphocytes for investigating complement activation and pharmacokinetics through alternations in the plasma membrane integrity. We functionalized the surface of tantalum oxide gate insulator of ISFET with oleyl-tethered phosphonic acid for interacting with the plasma membranes of floating cells without affecting the cell signaling. The surface modification was characterized by X-ray photoelectron spectroscopy and water contact angle measurements. The Nernst response of −37.8 mV/pH was obtained for the surface-modified ISFET at 37 °C. The oleyl group-functionalized gate insulator successfully captured Jurkat T cells in a fluidic condition without acute cytotoxicity. The system was able to record the time course of pH changes at the cells/ISFET interface during the process of instant addition and withdrawal of ammonium chloride. Further, the plasma membrane injury of floating cells after exposure by detergent Triton™ X-100 was successfully determined using the modified ISFET with enhanced sensitivity as compared with conventional hemolysis assays. Abstract : UF0001