Hostname: page-component-594f858ff7-wfvfs Total loading time: 0 Render date: 2023-06-09T01:58:41.764Z Has data issue: false Feature Flags: { "corePageComponentGetUserInfoFromSharedSession": true, "coreDisableEcommerce": false, "corePageComponentUseShareaholicInsteadOfAddThis": true, "coreDisableSocialShare": false, "useRatesEcommerce": true } hasContentIssue false

Prediction of the Mass Sensitivity of Phage-Coated Magnetoelastic Biosensors for the Detection of Single Pathogenic Bacteria

Published online by Cambridge University Press:  18 April 2011

Shin Horikawa
Materials Research and Education Center, Auburn University, AL 36849, U.S.A.
Suiqiong Li
Materials Research and Education Center, Auburn University, AL 36849, U.S.A.
Yating Chai
Materials Research and Education Center, Auburn University, AL 36849, U.S.A.
Valerly A. Petrenko
Department of Pathobiology, Auburn University, AL 36849, U.S.A.
Bryan A. Chin
Materials Research and Education Center, Auburn University, AL 36849, U.S.A.
Get access


Freestanding, strip-shaped magnetoelastic (ME) biosensors are a class of wireless, mass-based biosensors that are being developed for the real-time detection of pathogenic bacteria for food safety and bio-security. The mass sensitivity of these biosensors operating in longitudinal-vibration modes is known to be largely dependent on the position of masses attached to the sensor surfaces. Hence, considering this dependence is crucial to the detection of low-concentration target pathogens, including single pathogenic bacteria, because their local attachment may cause varying sensor responses. In a worst case scenario, the resultant sensor responses (i.e., mass-induced resonance frequency changes of the sensor) may be too small to be detected despite the attachment of the target pathogenic masses. To address the issue, phage-coated ME biosensors (magnetostrictive strips (4 mm × 0.8 mm × 30 μm) coated with a phage probe specifically binding streptavidin protein) with localized masses (streptavidin-coated polystyrene beads) were fabricated, and mass-position-dependence of the sensor’s sensitivity under the fundamental-mode vibration was experimentally measured. In addition, three-dimensional finite element (FE) modal analysis was performed using the CalculiX software to simulate the phenomena. The experimental and theoretical results show close agreement: (1) the mass sensitivity was low when the mass was positioned in the middle of the sensor’s longest dimension and (2) a much higher mass sensitivity was, by contrast, obtained for the equivalent masses placed at both ends of the strip-shaped sensor. Furthermore, FE models were constructed for differently sized, phage-coated ME biosensors (100 – 500 μm in length with different widths and thicknesses) loaded with a single bacterial mass (2 μm × 0.4 μm × 0.4 μm, 1.05 g/cm3) at varying longitudinal positions. The mass sensitivity was found to be approximated by a mass-position-dependent Boltzmann function whose amplitude is inversely proportional to the length squared, width, and thickness of the sensor.

Research Article
Copyright © Materials Research Society 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)



1. Grimes, C. A., Mungle, C. S., Zeng, K., Jain, M. K., Dreschel, W. R., Paulose, M., and Ong, K. G., Sensors, 2, 294 (2002).CrossRefGoogle Scholar
2. Liang, C., Morshed, S., and Prorok, B. C., Appl. Phys. Lett., 90, 221912 (2007).CrossRefGoogle Scholar
3. Huang, S., Hu, J., Wan, J., Johnson, M., Shu, H., and Chin, B., Mater. Sci. Eng., C, 28, 380 (2008).CrossRefGoogle Scholar
4. Rai, U. and Singh, R., Materials Letters, 58, 235 (2003).CrossRefGoogle Scholar
5. Gupta, A. and Akin, D., J. Vac. Sci. Technol., B, 22, 2785 (2004).CrossRefGoogle Scholar
6. Yao, X., Jericho, M., Pink, D., and Beveridge, T., J. Bact., 181, 6865 (1999).Google Scholar