Thermoelectric Properties of Fe0.2Co3.8Sb12-xTex ... - Physics

Bio – sensors based on electrical and optical properties of
Carbon nanotubes & Graphene oxide
K. S. Vasu a , S. Sridevi b , S. Asokan b , N. Jayaraman c and A. K. Sood a
a Department of Physics, Indian Institute of Science, Bangalore
b Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore
c Department of Organic Chemistry, Indian Institute of Science, Bangalore.
We show that single walled carbon nanotubes (SWNTs) decorated with sugar functionalized
poly (propyl ether imine) (PETIM) dendrimer (DM) is a very sensitive platform to quantitatively
detect carbohydrate recognizing proteins, namely, lectins. The mannose attached PETIM
dendrimers undergo charge – transfer interactions with the SWNT. The changes in the
conductance of the dendritic sugar functionalized SWNT after addition of lectins in varying
concentrations were found to follow the Langmuir type isotherm, giving the concanavalin A
(Con A) – mannose affinity constant to be 8.5 x 10 6 M -1 [1].
We have recently shown that etched Fiber Bragg Gratings (eFBGs) coated with nano – carbon
materials can be used as potential biochemical sensors. The shift in the Bragg wavelength (∆λ B )
with respect to the λ B values of SWNT (or GO) – DM coated eFBG for various concentrations of
lectin follows Langmuir type adsorption isotherm and quantitatively analyzed to establish the
detection limit [2].
References:
1) K. S. Vasu, K. Naresh, R. S. Bagul, N. Jayaraman and A. K. Sood, Appl. Phys. Lett. 101,
053701 (2012).
2) S. Sridevi, K.S. Vasu, N. Jayaraman, S. Asokan and A.K. Sood (2013).