Chemiresistor urea sensor

Patent · Tue Dec 31 23:00:00 EST 1996

OSTI ID:871276

Glass, Robert S ^[1]

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1. Livermore, CA

A sensor to detect and quantify urea in fluids resulting from hemodialysis procedures, and in blood and other body fluids. The sensor is based upon a chemiresistor, which consists of an interdigitated array of metal fingers between which a resistance measured. The interdigitated array is fabricated on a suitable substrate. The surface of the array of fingers is covered with a coating containing the enzyme urease which catalyzes the hydrolysis of urea to form the ammonium ion, the bicarbonate ion, and hydroxide-chemical products which provide the basis for the measured signal. In a typical application, the sensor could be used at bedside, in conjunction with an appropriate electronics/computer system, in order to determine the hemodialysis endpoint. Also, the chemiresistor used to detect urea, can be utilized with a reference chemiresistor which does not contain urease, and connected in a differential measurement arrangement, such that the reference chemiresistor would cancel out any fluctuations due to background effects.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• DOE Contract Number: W-7405-ENG-48
• Assignee: Regents of University of California (Oakland, CA)
• Patent Number(s): US 5698083
• OSTI ID: 871276
• Country of Publication: United States
• Language: English

Related Subjects

/204/422/435/436/
ammonium
application
appropriate
appropriate electronics
arrangement
array
background
based
basis
bedside
bicarbonate
blood
cancel
catalyzes
chemical product
chemical products
chemiresistor
coating
coating containing
computer
conjunction
connected
consists
contain
containing
covered
detect
determine
differential
differential measurement
due
effects
electronics
endpoint
enzyme
fabricated
fingers
fluctuations
fluids
fluids resulting
form
hemodialysis
hemodialysis procedures
hydrolysis
hydroxide-chemical
interdigitated
measured
measured signal
measurement
metal
procedures
products
provide
quantify
reference
resistance
resistance measured
resulting
sensor
signal
substrate
suitable
suitable substrate
surface
typical
typical application
urea
urea sensor
urease
utilized