High-sensitivity detector for molecular sensing using magnetic particles

Authors

Damien Le Roy, University of Nebraska-LincolnFollow
W. Yang, Nebraska Center for Materials and Nanoscience
X. Yin, Nebraska Center for Materials and Nanoscience
R. Y. Lai, Nebraska Center for Materials and NanoscienceFollow
Sy_Hwang Liou, University of Nebraska-LincolnFollow
David J. Sellmyer, Nebraska Center for Materials and NanoscienceFollow

Document Type

Article

Date of this Version

2011

Citation

JOURNAL OF APPLIED PHYSICS 109, 07E532 (2011); doi:10.1063/1.3564951

Comments

Copyright 2011 American Institute of Physics

Abstract

A scheme for molecular sensing using magnetic tracer particles and a microcantilever torsional magnetometer is investigated. The present report deals with the example of explosive 2,4,6- trinitrotoluene (TNT) detection. The sensors consist of silicon microcantilevers functionalized with TNT aptamers that are weakly bonded to magnetic particles via TNT-analog molecules. When exposed to TNT, the magnetic signal, initially maximum, is expected to undergo a steplike decrease as the TNT molecules replace the magnetic particles on the TNT receptors. We demonstrate the feasibility of this detection technique in terms of chemical reactions and our magnetometer sensitivity that reaches the range of 10^‒11 emu at room temperature with commercial atomic force microcopy cantilevers.