Nanostructured ZnO films: A study of molecular influence on transport properties by impedance spectroscopy

SAPPIA, L.; RICARDO M TRUJILLO; LORITE, ISRAEL; MADRID, ROSSANA ELENA; TIRADO, MÓNICA; TIRADO, MÓNICA; COMEDI, DAVID; ESQUINAZI, PABLO

MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015 vol. 200 p. 124 - 131

0921-5107

Nanomaterials based on ZnO have been used to build glucose sensors due to its high isoelectric point,which is important when a protein like Glucose Oxidase (GOx) is attached to a surface. It also createsa biologically friendly environment to preserve the activity of the enzyme. In this work we study theelectrical transport properties of ZnO thin films (TFs) and single crystals (SC) in contact with differentsolutions by using impedance spectroscopy. We have found that the composition of the liquid, by meansof the charge of the ions, produces strong changes in the transport properties of the TF. The enzyme GOxand phosphate buffer solutions have the major effect in the conduction through the films, which canbe explained by the entrapment of carriers at the grain boundaries of the TFs. These results can help todesign a new concept in glucose biosensing.