Application of enzyme/zeolite sensor for urea analysis in serum

A Novel Conductometric Urea Biosensor with Improved Analytical Characteristic Based on Recombinant Urease Adsorbed on Nanoparticle of Silicalite

“…The zeolites are slightly toxic and highly resistant to mechanical, chemical, and thermal injuries [23]; therefore, the zeolite-based biosensors can be used for multicomponent biological samples. This method of immobilization demonstrated promising results in a number of enzyme biosensors [24][25][26].…”

Development of Multi-parameter Analyser based on Electrochemical Urea Biosensors and Electrolyte Electrodes for Monitoring of Hemodialysis Patients

“…Alternative technologies for urea measurements being developed are based on biosensor electrodes. They have different design approaches such as potentiometric (Kuralay et al, 2005, Liu et al, 1993Ahuja et al, 2011;Boubriak et al, 1995), conductometric (Soldatkin et al, 2014;Chen et al, 1994;Sangodkar et al, 1996) and amperometric (Sangodkar et al, 1996;Tiwari et al, 2009), they usually employ urease (EC 3.5.1.5) as a catalyst for urea breakdown, which is immobilized by a number of methods on electrode surface (Dhawan et al, 2009). The urease catalyses the hydrolysis of urea to yield ammonia and carbamic acid (equation 1) which spontaneously decomposes into carbonic acid and a second ammonia molecule (equation 2) (Carter et al, 2009), as shown below:…”

“…The electrodes and bioelectrodes (biosensors) used in such equipment should be accurate, not expensive, stable, simple to use in field measurement, etc. In case of possible urea biosensor, our scientific group until recently has been developing several types of urea biosensors (Boubriak et al, 1995;Soldatkin et al, 2014;Mc Causland et al, 2012;Laurinavicius et al, 2013). In this case a specific attention is paid to previously developed and published potentiometric (Kulys et al, 1986) and amperometric (Mc Causland et al, 2012) urea biosensors that were further developed, as described in this work.…”

A high-performance nonenzymatic piezoelectric sensor based on molecularly imprinted transparent TiO2 film for detection of urea

“…A physiological urea level is in a range from 2.5 to 7.5 mM, depending on the build and relative health of the body (Dhawan et al, 2009). A decreased urea level can be associated with severe liver disease or insufficient protein intake, and a high urea concentration can cause renal dysfunction, urinary tract obstruction, dehydration, shock and gastrointestinal bleeding (Soldatkin et al, 2014;Ahmad et al, 2014). Therefore, it is very important to monitor the level of urea to determine the health of the livers and kidneys in the human body.…”