TY - JOUR
T1 - Highly sensitive urea sensing with ion-irradiated polymer foils
AU - Fink, Dietmar
AU - Muñoz Hernandez, Gerardo
AU - Alfonta, Lital
N1 - Funding Information:
D.F. thanks the Universidad Autónoma Metropolitana, Iztapalapa, México City, for the guest professorship within the Catedra Marcos Menzer Mazari framework. We are especially obliged to Profs. S.A. Cruz and Mr. N. Camarillo from UAM-Iztapalapa and J.C. Terán from UAM-Cuajimalpa, for their continuous help and discussions and for providing us with adequate working facilities. We are further obliged to Dr. P. Apel from JNRI Dubna, Russia for providing us with the ion-irradiated foils. L.A. acknowledges the support of the Edmond J. Safra Center for the Design and Engineering of Functional Biopolymers at Ben-Gurion University.
PY - 2012/2/15
Y1 - 2012/2/15
N2 - Recently we prepared urea-sensors by attaching urease to the inner walls of etched ion tracks within thin polymer foil. Here, alternative track-based sensor configurations are examined where the enzyme remained in solution. The conductivities of systems consisting of two parallel irradiated polymer foils and confining different urea/urease mixtures in between were examined. The correlations between conductivity and urea concentration differed strongly for foils with unetched and etched tracks, which points at different sensing mechanisms - tentatively attributed to the adsorption of enzymatic reaction products on the latent track entrances and to the enhanced conductivity of reaction product-filled etched tracks, respectively. All examined systems enable in principle, urea sensing. They point at the possibility of sensor cascade construction for more sensitive or selective sensor systems.
AB - Recently we prepared urea-sensors by attaching urease to the inner walls of etched ion tracks within thin polymer foil. Here, alternative track-based sensor configurations are examined where the enzyme remained in solution. The conductivities of systems consisting of two parallel irradiated polymer foils and confining different urea/urease mixtures in between were examined. The correlations between conductivity and urea concentration differed strongly for foils with unetched and etched tracks, which points at different sensing mechanisms - tentatively attributed to the adsorption of enzymatic reaction products on the latent track entrances and to the enhanced conductivity of reaction product-filled etched tracks, respectively. All examined systems enable in principle, urea sensing. They point at the possibility of sensor cascade construction for more sensitive or selective sensor systems.
KW - Biosensors
KW - Polymers
KW - Tracks
KW - Urea
KW - Urease
UR - http://www.scopus.com/inward/record.url?scp=84856102569&partnerID=8YFLogxK
U2 - 10.1016/j.nimb.2011.07.066
DO - 10.1016/j.nimb.2011.07.066
M3 - Article
AN - SCOPUS:84856102569
SN - 0168-583X
VL - 273
SP - 164
EP - 170
JO - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
JF - Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
ER -