Potentiometric Urea Biosensor Based on an Immobilised Fullerene-Urease Bio-Conjugate
Open Access
- 6 December 2013
- Vol. 13 (12), 16851-16866
- https://doi.org/10.3390/s131216851
Abstract
A novel method for the rapid modification of fullerene for subsequent enzyme attachment to create a potentiometric biosensor is presented. Urease was immobilized onto the modified fullerene nanomaterial. The modified fullerene-immobilized urease (C60-urease) bioconjugate has been confirmed to catalyze the hydrolysis of urea in solution. The biomaterial was then deposited on a screen-printed electrode containing a non-plasticized poly(n-butyl acrylate) (PnBA) membrane entrapped with a hydrogen ionophore. This pH-selective membrane is intended to function as a potentiometric urea biosensor with the deposition of C60-urease on the PnBA membrane. Various parameters for fullerene modification and urease immobilization were investigated. The optimal pH and concentration of the phosphate buffer for the urea biosensor were 7.0 and 0.5 mM, respectively. The linear response range of the biosensor was from 2.31 × 10−3 M to 8.28 × 10−5 M. The biosensor’s sensitivity was 59.67 ± 0.91 mV/decade, which is close to the theoretical value. Common cations such as Na+, K+, Ca2+, Mg2+ and NH4+ showed no obvious interference with the urea biosensor’s response. The use of a fullerene-urease bio-conjugate and an acrylic membrane with good adhesion prevented the leaching of urease enzyme and thus increased the stability of the urea biosensor for up to 140 days.Keywords
This publication has 25 references indexed in Scilit:
- Potentiometric urea biosensor based on multi-walled carbon nanotubes (MWCNTs)/silica composite materialMaterials Science and Engineering: C, 2011
- An amperometric urea biosensor based on covalently immobilized urease on an electrode made of hyperbranched polyester functionalized gold nanoparticlesTalanta, 2009
- Recent developments in urea biosensorsBiochemical Engineering Journal, 2009
- Polymer Based Urea Biosensors: A Brief OverviewSensor Letters, 2008
- Amperometric enzyme electrode for urea determination using immobilized urease in poly(vinylferrocenium) filmSensors and Actuators B: Chemical, 2006
- An amperometric urea biosensor based on covalent immobilization of urease onto an electrochemically prepared copolymer poly (N-3-aminopropyl pyrrole-co-pyrrole) filmBiomaterials, 2004
- Optical biosensor for urea with improved response timeBiosensors and Bioelectronics, 2002
- Conductometric uric acid and urea biosensor prepared from electroconductive polyaniline–poly(n-butyl methacrylate) compositesSensors and Actuators B: Chemical, 2002
- An Integrated Thermal Biosensor Array for Multianalyte Determination Demonstrated with Glucose, Urea and PenicillinAnalytical Letters, 1996
- Thermal enzyme probe with differential temperature measurements in a laminar flow-through cellAnalytical Chemistry, 1980