Based on the detection mechanism, we recently proposed an analytical model for the detection of DNA molecules in which the DNA concentration BAY 11-7082 in vivo was modelled by a gate voltage [2]. Although there

are lots of works presented on the experimental progress, however, far too little attention has been paid to the detection mechanism quantitatively. For supporting this, modelling and simulation using partial differential equations (PDE) play a critical role in determining the current-voltage characteristics, sensitivity and the behaviour of the sensing devices www.selleckchem.com/products/fosbretabulin-disodium-combretastatin-a-4-phosphate-disodium-ca4p-disodium.html exposing to DNA molecules. Our proposed model is capable of performing the electrical detection of DNA molecules by modelling the conductance of the graphene sheets. Based on the sensing mechanism inspired by the experiment to investigate the effect of

DNA adsorption on graphene, DNA concentration as a function of gate voltage is assumed and ARN-509 chemical structure sensing factor (α) is defined. High carrier mobility reported from experiments in the graphene leads to assume a completely ballistic carrier transportation in the graphene [31]. Subsequently, FET modelling was employed to obtain relevance between current versus voltage of gate sensor. The DNA concentration model is employed as a function of gate voltage and the ideal current-voltage relation for the n-channel FET in the non-saturation region from reference [32] is obtained as: (1) Where q is the electron charge, a = 1.42Å denotes carbon-carbon Benzatropine (C - C) bond length, t = 2.7 eV is the nearest

neighbour C - C tight binding overlap energy, k B is the Boltzmann’s constant, T represents temperature and h is the Planck’s constant. L shows the length of conducting channel, V gs donates the gate-source voltage and V t refers to the threshold voltage. Furthermore, ȷ -0.5(η) and ȷ -0.5(-η) are the Fermi-Dirac integrals of orders -0.5 which can be solved numerically. Its value depends on η which measures the location of the Fermi level with respect to the conduction band edge. The Fermi-Dirac distribution function has different forms in degenerate and non-degenerate states which are attributed by (η ≫ 0) and (η ≪ 0), respectively [5, 32]. α is DNA sensing factor and different concentration of DNA molecules were presented in the form of F parameter. Thus, the DNA molecules adsorbed on graphene surface by iteration method was modelled as (2) A = 13, B = 50 and C = 4,070 are the parameters calculated based on the extracted data. The current-voltage characteristic of SGFET according to the proposed model of DNA sensor using nanostructured graphene layer is obtained as: (3) It is concluded that the sensor model with the suggested parameters represents the same trend as experimental data [2, 6].