Biosensors & Bioelectronics

In medical and health care applications it was always desirable to perform pre-processing and conditioning on the sensor raw output before data acquisition. Based on this requirement, biosensor was proposed and designed using conducting polymers and nano - materials which was having In- situ Signal Conditioning Electronics that eliminates need for additional on board hardware circuitry. This advanced signal-conditioning circuit mainly consists of an ASIC with associated components that process the raw output from bio-sensor. The ASIC works with lowvoltage and low-current, with wide operating temperature range. The bio-sensor, which was designed very much sensitive to room temperature and pressure. Nano-bio sensor ASIC operates at +5V input and provides an output of 0 to 500 mV for absolute sensor output of 0 to 500 nano-amps or pico-amps. Further efforts were initiated to incorporate high resolution ADC with the signal conditioning electronics that gives a serial digital output directly using SPI interface on Mixed-Signal Processor (MSP). This research work aimed at suitable signal-conditioning and processing electronics using ASIC on MSP. The ASIC designed expected to have various on-chip programmable features for enabling interface compatibility with wide variety of (sample/analyte) sensors and to achieve process variations using mixed signal processor (MSP). The work is focussed on Optimised Design of Smart Sensor using Conducting Polymer and Gold/Silver/CNT Nanocomposites .Polyaniline (PANY) has been selected as the Conducting polymer on which surface CNT thin layer will be deposited using Sol-Gel technique.Here more emphasis is given to Bio-Signal (which was generated or simulated by the electronic circuit in the laboratory) Conditioning and processing using MSP for biological real time applications.Further the synthesis and characterization of the thin film or the designed sensor will be carried out at IISC Nano-FAB lab under INUP programme.

All biological molecules and cell organelles are chemo mechanically controlled systems known to every biologist. The control signals governing them are electrical. The influence of an electric field in them makes a disturbance such that they behave as an electronic distributed network. It is an interdisciplinary art to activate them and work as an electronic device. Modeling the biological molecules as per the devices is by understanding their stability and work functions. Here a micro tubule (MT) molecule is modeled to function as a diode in electronic parameters, there by not disturbing its biological function. The MT is similar to its other cytoskeleton filament. In its two dimers alpha and beta, in the tunneling effect of the ions, can establish the diode characteristics in its conductivity of electric ionic current.