Laminated, microfluidic-integrated carbon nanotube based biosensors

Abstract

In this communication, a laminated, flexible, microfluidic-integrated, all CNT based liquid-gated transistor and biosensor are reported that comprises single walled CNTs for both the semiconducting channel as well as the contact electrodes. The proposed architecture eliminates the need for lithography, electrode definition processes, and also circumvents substrate surface compatibility issues. Real-time detection of 1 pM poly-L-lysine in a liquid-gated transistor comprising only two materials, single walled CNTs and polydimethoxysilane substrate with microfluidic channel, is demonstrated.

Nanotubes-/nanowires-based, microfluidic-integrated transistors for detecting biomolecules

“…4). Of these possible mechanisms, a series of studies have shown that the predominant sensing mechanism in LGFET comes from electrostatic gating (Curreli et al 2008;Li et al 2005;Maehashi et al 2006;Tey et al 2009;Wijaya et al 2009) and/or Schottky barrier modulation (Gui et al 2007;Byon and Choi 2006).…”

“…However, the use of planar substrate instead of the nanostructured material as the sensing element might limit the achievable sensitivity of the platform. Figure 6c shows another approach using a two-step lamination process for LGFET fabrication (Tey et al 2009), in which the use of silicon substrate is no longer required. The detailed fabrication process of this laminated CNT-LGFET is exemplified in Fig.…”

Sensors at the micro-scale

“…Carbon nanotubes (CNTs) have attracted interest in biosensing applications [32][33][34][35]. For example, CNT biosensors were used for real-time detection of poly-L-lysine with a detection limit of ∼1 pM [32]. In [34], CNT FET device networks were found to be extremely sensitive to the addition of ultralow concentrations of DNA, down to 0.1 fM, which is equivalent to ∼100 DNA molecules.…”

“…Carbon nanotubes (CNTs) have attracted interest in biosensing applications [32][33][34][35]. For example, CNT biosensors were used for real-time detection of poly-L-lysine with a detection limit of ∼1 pM [32].…”

Detection of sugar-lectin interactions by multivalent dendritic sugar functionalized single-walled carbon nanotubes

“…In electronic impedance spectroscopy method, the carbohydrate modified boron doped diamond surfaces have been used to investigate carbohydrate-protein interactions [15]. Due to the excellent electronic properties of the SWNTs, the field effect transistor (FET) 3 made of SWNTs and chemically modified SWNTs were used as protein biosensors [16,17].…”