Simulation of perforated rectangular cantilever immunosensor for estimation of bacterial pathogens

J. Sakthi Swarrup, K. Govardhan, V. Velmurugan

.

DOI: 10.4236/health.2010.211184                

Abstract

Micro fabricated and multilayered perforated cantilever beam immunosensor was modeled using CoventorWare for the estimation of bacterial antigens of Bacillus Anthrax, Pseudomonas aeruginosa, Coryne Bacterium Diptheria and Treponema pallidum. A rectangular cantilever beam with perforations was simulated with dimensions as length-200 µm, width-10 µm and thickness-0.5 µm. Each perforation is rectangular with length-10 µm, width-5 µm and thickness-0.5 µm. The theoretical and FEM simulations were carried out with five immunoglobulin antibodies, IgA, IgD, IgE, IgG and IgM for the estimation of bacterial antigens. The effect of perforation in cantilever beam and molecular size of antibody and antigen on the performance of the sensor has been studied. The cantilever beam without perforation showed a deflection of 1.8 e + 02 µm whereas the cantilever beam with perforation showed an increase deflection of 1.9 e + 02 µm. With IgG, the difference between analytical and simulation values is positive and low especially with low molecular weight antigens Pseudomonas aeruginosa and Treponema pallidum. The low molecular weight IgG influences the antigen-antibody interaction more fvourably. The simulated perforated rectangular cantilever beam with IgG antibody is a more promising model for the fabrication of a sensor for the estimation of highly motile Pseudomonas aeruginosa and Treponema pallidum.

Keywords

Modeling; Perforated Rectangular Cantilever Beam; Immunosensor; Immunoglobulin Antibodies; Estimation of Bacterial Pathogen Antigen

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Hagan, M.F. and Chakraborty, A.K. (2004) Hybridization dynamics of surface immobilized DNA. Journal of Physical Chemistry, 120, 4958-4968.
[2]	Hagan, M.F., Majumdar, A. and Chakraborty, A.K. (2002) Nanomechanical forces generated by surface-grafted DNA. Journal of Physical Chemistry B, 106, 10163-10173.
[3]	Stachowiak, J.C., Yue, M., Castelino, K., Lacevic, N., Chakraborty, A.K. and Majumdar, A. (2006) Chemomechanics of surface stresses induced by biomolecular reactions. Langmuir, 22, 263-268.
[4]	Fritz, J., Baller, M.K., Lang, H.P., Rothuizen, H., Vettiger, P., Meyer, E., Güntherodt, H.J., Gerber, C. and Gimzewski, J.K. (2000) Translating biomolecular recognition into nanomechanics. Science, 288, 316-318.
[5]	Wu, G., Ji, H., Hansen, K., Thundat, T., Datar, R., Cote, R., Hagan, M.F., Chakraborty, A.K. and Majumdar, A. (2001) Origin of nanomechanical cantilever motion generated from biomolecular interactions. Proceedings of National Academy of Science, 98, 1560-1564.
[6]	Wu, G., Datar, R., Hansen, K., Thundat, T., Cote, R. and Majumdar, A. (2001) Bioassay of prostate specific antigen using microcantilevers. Nature Biotechnology, 19, 856-860.
[7]	Ramos, D., Tamayo, J., Mertens, J., Calleja, M. and Zaballos, A. (2006) Origin of the response of nanomechanical resonators to bacteria adsorption. Journal of Applied Physics, 100, 106105.
[8]	Ramos, D., Calleja, M., Mertens, J., Zaballos, A. and Tamayo, J. (2007) Measurement of the mass and rigidity of adsorbates on a microcantilever sensor. Sensors, 7, 1834-1845.
[9]	Craighead, H. (2007) Nanomechanical systems-measureing more than mass. Nature Nanotechnology, 2, 18-19.
[10]	Schnell, S. and Turner, T.E. (2004) Reaction kinetics in intracellular environments with macromolecular crowd- ing: Simulations and rate laws. Progress in Biophysics and Molecular Biology, 85, 235-260.