Page 237 - Polymer-based Nanocomposites for Energy and Environmental Applications

Polymer nanocomposites for sensor devices 209

Fig. 7.2 Schematic representation of the fabrication of L-MMT/ITO electrode for
cholesterol sensor.
Reproduced from Joshi N, Rawat K, Solanki PR, Bohidar HB. Enzyme-free and biocompatible
nanocomposites based cholesterol sensor. Biochem Eng J 2015;102,69–73, with permission
from Elsevier Science.

The preparation of nanocomposites is carried by gelation process by mixing clay
laponite (L)-montmorillonite (MMT) in aqueous dispersion in equimolar proportion
(L/MMT¼1:1). The nanocomposite film produced from homogeneous gel was
transparent and had good thermomechanical properties. The sensor electrodes were
prepared by drop casting method by the deposition of indium tin oxide (ITO) on glass
plates. By cyclic voltammetry method, the detection of ascorbic acid (AA), oxalic acid
(OA), glucose (Glu), and cholesterol (ChO) in the concentration range of 1–20 mM.
In this process, the prepared electrode of nanocomposites was used. However, it was
observed that the sensor was more sensitive toward cholesterol detections. Schematic
representation of the fabrication of L-MMT/ITO electrode for cholesterol sensor is
represented in Fig. 7.2. The advantages for using nanoclay were due to its stability,
the presence of anisotropic charged particles, high surface charge density, and its
controlled structure.

7.4.2 Development of the flexible pressure sensor

Aligned carbon nanotube (A-CNT)-based pressure sensor was developed for the mea-
surement of blood pressure. Which can be attached to a stent graft and deployed during
an endovascular aneurysm repair procedure [20]? Fabrication of capacitive sensors
was done by embodiment of A-CNT flexible substrate with PDMS. The growth