Growth and Structure of ZnO Nanorods on a Sub-Micrometer Glass Pipette and Their Application as Intracellular Potentiometric Selective Ion Sensors

Muhammad H Asif; Omer Nur; Magnus Willander; Peter Strålfors; Cecilia Brännmark; Fredrik Elinder; Ulrika H Englund; Jun Lu; Lars Hultman

doi:10.3390/ma3094657

Growth and Structure of ZnO Nanorods on a Sub-Micrometer Glass Pipette and Their Application as Intracellular Potentiometric Selective Ion Sensors

Materials (Basel). 2010 Sep 9;3(9):4657-4667. doi: 10.3390/ma3094657.

Authors

Muhammad H Asif¹, Omer Nur², Magnus Willander³, Peter Strålfors⁴, Cecilia Brännmark⁵, Fredrik Elinder⁶, Ulrika H Englund⁷, Jun Lu⁸, Lars Hultman⁹

Affiliations

¹ Department of Science and Technology, Campus Norrköping, Linköping University, SE-60174 Norrköping Sweden. muhas@itn.liu.se.
² Department of Science and Technology, Campus Norrköping, Linköping University, SE-60174 Norrköping Sweden. omeno@itn.liu.se.
³ Department of Science and Technology, Campus Norrköping, Linköping University, SE-60174 Norrköping Sweden. magwi@itn.liu.se.
⁴ Department of Clinical and Experimental Medicine, Division of Cell Biology, Linköping University, SE-58185 Linköping, Sweden. peter.stralfors@liu.se.
⁵ Department of Clinical and Experimental Medicine, Division of Cell Biology, Linköping University, SE-58185 Linköping, Sweden. cecilia.brannmark@gmail.com.
⁶ Department of Clinical and Experimental Medicine, Division of Cell Biology, Linköping University, SE-58185 Linköping, Sweden. fredrik.elinder@liu.se.
⁷ Department of Clinical and Experimental Medicine, Division of Cell Biology, Linköping University, SE-58185 Linköping, Sweden. ulrika.englund@liu.se.
⁸ Department of Physics (IFM), Linkoping University, SE-581 83 Linköping, Sweden. junlu@ifm.liu.se.
⁹ Department of Physics (IFM), Linkoping University, SE-581 83 Linköping, Sweden. larhu@ifm.liu.se.

Abstract

This paper presents the growth and structure of ZnO nanorods on a sub-micrometer glass pipette and their application as an intracellular selective ion sensor. Highly oriented, vertical and aligned ZnO nanorods were grown on the tip of a borosilicate glass capillary (0.7 µm in diameter) by the low temperature aqueous chemical growth (ACG) technique. The relatively large surface-to-volume ratio of ZnO nanorods makes them attractive for electrochemical sensing. Transmission electron microscopy studies show that ZnO nanorods are single crystals and grow along the crystal's c-axis. The ZnO nanorods were functionalized with a polymeric membrane for selective intracellular measurements of Na⁺. The membrane-coated ZnO nanorods exhibited a Na⁺-dependent electrochemical potential difference versus an Ag/AgCl reference micro-electrode within a wide concentration range from 0.5 mM to 100 mM. The fabrication of functionalized ZnO nanorods paves the way to sense a wide range of biochemical species at the intracellular level.

Keywords: HRTEM; ZnO nanorods; functionalization; intracellular sensor; membrane.