BIOSENSORSBy Dominic Lanni

Overview of Biosensors

Part One

Introduction

What are biosensors? A device that uses a living organism or

biological molecule to detect things Usually chemicals, heavy metals,

pathogens

Famous Person

Pioneer of technology is Anthony P. F. Turner

Introduced screen-printing techniques

Developed blood-glucose sensors for diabetics

Types of Biosensors

Can be Electrochemical

(Amperometry)Electrical (Conductivity)Optical (Fluorescence)Mass Sensitive

(Piezoelectric frequency)Thermal (Heat of

reaction/adsorption)

Design ProposalPart Two

Purpose

Dysentery-not fun (duh) Caused by an amoeba or a

bacterium called Shigella No vaccine available

(although there are treatments)

Proposal: a Mass-Sensitive BiosensorWill detect bacteria in water

Competing Technologies

Conventional bacterial cultures

Immunological methods

Molecular microbiological methods

The Design Mass-sensitive

Utilizes piezoelectric quartz crystal

DNA probe attached to crystal

Water sample put through DNA isolation process, and heated to denature strandsPCR may also be performed

The Design DNA is pipetted in, and

heated to 50 degrees Celsius

Strands anneal to probe, increasing mass of crystal

Change in mass creates change in frequency

Change in frequency signals presence of Shigella

Expected Results

If the frequency emitted by the crystal changes, then DNA has bound to probe

If DNA binds to probe, then Shigella bacteria are present in water sample

Knowledge of contamination prevents spreading and contraction of dysentery

Advantages

No lack of supplies, as in bacterial cultures

Can be extremely fast Crystals are cheap

Potential Problems Could be difficult to assemble on a large scale PCR would slow down process if necessary for

success Portable power source for whole system necessary, as

finding an outlet may be difficult Crystals can degrade in quality over time

Testing

Tests to determine how accurate device is

Tests to determine if PCR is necessary or not

Environmental tests to determine hardiness of device and crystals

THIS CONCLUDES THE

PRESENTATIONHope you learned something.

I don’t care what.

Anything is great.