Abstract

The development of biosensors to measure the concentration of dissolved oxygen in the blood began. This sensor is also called COBD because it covers the surface of the electrode with an enzyme whose constituent is sometimes called (electro-calorie). Later, it helped oxidize glucose. This sensor was used to measure blood sugar. In the same Bapvshandn electrode, an enzyme that has the ability to convert urea into ammonium carbonate in the electrode material ++ ion, NH4, was used to create biosensors that could measure the urea in the blood or urine. Each of these two early biosensors used a different transducer in its signal conversion section . In the first type, blood sugar was measured by measuring the electric current generated (ammetric),while in the urea sensor, the urea concentration was measured based on the electric charge created sensors are made (.Potentiometric) may someday the patient without having to visit a doctor and only on the basis of information that a COBD or Doctor-Board-on-Chip provides, the type of disease has been detected. And then injected into the blood. This will drastically reduce the dosage of the required drugs directly from the side effects of the Effect-Side drug , because the drug is very low and is also sent to the required place in the body. The drug acts directly on a biosensor that converts the biological response into an electrical signal and consists of two main components: the receptor and the detector. The ability to select one biosensor is determined by the receiving section. Enzymes, antibodies, and lipid layers are good examples of receptors. The task of the detector is to convert the physical or chemical changes by detecting the material to be analyzed into an obvious factor that the detectors can select in the type of reaction of the electrical signal. They do not have the perfect .They are electrochemical, optical, piezoelectric, and thermal. In the type of electrochemistry the action takes place in one of the following ways: amperometric, potentiometric, and impedance. The most common electrodes used in the potentiometric type include: the Glass electrode, the Selective-Ion ion electrode, and the FET sensitive-Ion ion field-effect transistor or ISFET. In general, a biosensor consists of an immobilized static biological system, such as a cell bundle, a micro enzyme, or an antibody, and a measuring. In the presence of a certain molecule, the biological system changes the properties of the environment.