Surface-modified Diamond Field-effect Transistors for Enzyme-immobilized Biosensors

Abstract

The enzyme sensors using electrolyte-solution-gate diamond field effect transistors (SGFETs) have been developed for the first time. The hydrogen-terminated surface channel of the FETs was modified into partially aminated and oxygen-terminated (H-A-O-terminated) with irradiation of ultraviolet in an ammonia environment. The pH response of that is obtained about 50 mV/pH at pH 2–10. The concentration of substrates (urea or glucose) in the electrolyte solution has been detected by the pH change due to the bio-catalyzed effect of enzyme (urease or glucose oxidase), which is immobilized on the channel of SGFETs. The sensitivity of urea and glucose is approximately 30 mV/decade and 20 mV/decade respectively.

Diamond‐based DNA sensors: surface functionalization and read‐out strategies

“…The diamond surface has been functionalized successfully with various biomolecules: not only with DNA as was already discussed, but also with immunoglobulins G and M (IgG and IgM) [70], and enzymes such as catalase [71], urease, glucose, oxidase [72], and horse radish peroxidase [73].…”

Characterisation of capacitive field-effect sensors with a nanocrystalline-diamond film as transducer material for multi-parameter sensing

“…For instance, the potential use of diamond for direct electrical sensing of biological binding events such as DNA hybridisation and antibody-antigen binding was demonstrated in (Yang and Hamers, 2004;Song et al, 2006a;Yang et al, 2006;. An enzyme-modified diamond-based field-effect transistor (FET) has been realised for the detection of urea and glucose (Song et al, 2004). The pH-and ion-sensitive properties of an electrolyte-gate FET with monocrystalline and polycrystalline diamond surfaces have been investigated in (Song et al, , 2006bKanazawa et al, 2003;Kawarada et al, 2001;Denisenko et al, 2007;Garrido et al, 2005;Rezek et al, 2006Rezek et al, , 2007Nebel et al, 2006aNebel et al, , 2006bDankerl et al, 2008).…”

Penicillin detection with nanocrystalline‐diamond field‐effect sensor

“…The possibility of application of diamond for a direct electrical sensing of molecular binding events such as DNA hybridisation and antibody-antigen affinity reaction was demonstrated in [4,5]. An enzyme-modified diamondbased field-effect transistor (FET) has been realised for the detection of urea and glucose [6]. The pH-and ionsensitive properties of an electrolyte-gate FET with monocrystalline and polycrystalline diamond surfaces have been investigated in [7][8][9][10][11][12][13][14][15].…”