PRODUCT AND THEIR APPLICATION

As the product has been designed with the sole aim of monitoring urea levels in body fluid,it will be of direct applied value,in paramedical sciences,to medical practitioners,common man and chronic patients.It can also be used as an analytical tool for routine laboratory estimations of urea concentration in different solutions.An important application is in the area of agriculture and hydroponics where the precise estimation of urea can be performed in soil samples.statisticl evidence can thus be obtained on the role of urea based fertilizers on crop yield.The sensor will enable rapid experimentation and thereby provide an indispensible tool for crop management.

DEMAND POTENTIAL

The need for a fast sensing urea probe is an absolute requirement of the present-day society with the increasing problem of diabetes and malfunctioning of kidney and liver due to air pollution and in take of toxic compounds.The sensor will also serve as a bedside tool for rapid monitoring of urea in suspected patients and will help medical practioners for providing preventive medicine.As the quantity of sample required is only one drop of blood,it is practically a user friendly technology and will befriend even a layman. Secondly it would serve an important requirement in the agricultural sector where a rapid analytical tool for measurement of urea content in soils and fertilizers is an absolute necessity.The interesting features of this device,its low cost,ease of operation and quick results.An additional feature would be the display of messages advising the patient on his blood urea status.

MANUFACTURING PROCESS

The manufacturing process consists of two stages 1)the synthesis and charcterization of membrane containing immobilized urease(the enzyme for specific detection of urea)and 2) the calibration of the P? probe for monitoring P? changes related to urea concentration.

Presently the method of detection is based on on the principle of potentiometry.This can however be made amperomtric by suitably modifying the measurement techniques using conducting polymers.In the potentiometric mode of detection the change in the potential at the working electrode tha contains the immoblized emzyme and which is the site of the reaction is monitored with respect to a standard reference electrode. The change in potential is measured as a function of time and the value of potential at a given time is used for developing a calibration curve. .However ,for the amperometric mode of detection the integration of the sensing electrode with the reaction products is systematically investigated.Results obtained so far indicate that a plausible model for amperometric mode of urea detection can be used for realtime monitoring of urea.The important aspect is the standardization of the PH Probe to be used for the detection of the PH changes due to the breakdown of molecule in the presence of urease.The following reaction essentially occurs:

UREASE

Urea + H2O --------------- Ammounium ions + Bicarbonate ions.The urea can be montiored either in the buffer solution,in blood serum or in whole blood. The PH probe is calibrated using standard buffer,to an accuracy of+/– 0.01 units.It may be mentioned that in the reaction of urease with urea it generates ammonia and carbon dioxide as the end products.The ammonia in the aqueous medium gets converted to ammonium ions whereas the carbondioxide dissolves in the aqueous medium and gets converted to bicarbonate ions.However bicarbonate being a weakly dissociating acid,contributes very little to PH changes,but the ammonium ions are strongly alkaline and hence the net PH shifts towards the alkaline side.