This letter reports a new technique that enables simultaneous detection of concentrations of the organic and inorganic substances in a hybrid fluidic solution. The technique is based on a coplanar microwave distributed MEMS transmission line. Measurement results show that a hybrid aqueous solution with a mixture of 0 M -- 0.2 M NaCl and 0 mg/ml -- 350 mg/ml glucose can be easily detected simultaneously from measured one-port scattering parameter (S11).
2. Norgren, M., "On the problem with intermodal dispersion when using multiconductor transmission lines as distributed sensors," Progress In Electromagnetic Research, Vol. 56, 129-150, 2006.
3. Shaforost, E. N., N. Klein, S. A. Vitusevich, A. A. Barannik, and N. T. Cherpak, "High sensitivity microwave characterization of organic molecule solutions of nanoliter volume," Applied Physics Letters, Vol. 94, 112901, 2009.
4. Dimitrakis, G. A., M. George, M. Poliakoff, I. Harrison, J. Robinson, S. Kingman, E. Lester, A. P. Gregory, and K. Lees, "A system for traceable measurement of the microwave permittivity of liquids at high pressures and temperatures," Measurement Science and Technology, Vol. 20, 045901, 2009.
5. Garcia-Banos, B., F. Cuesta-Soto, A. Griol, J. M. Catala-Civera, and J. Pitarch, "Enhancement of sensitivity of microwave planar sensors with EBG structures," IEEE Sensors Journal, Vol. 6, 1518-1522, 2006.
6. Li, L. and D. Uttamchandani, "Flip-chip distributed MEMS transmission lines (DMTLs) for biosensing applications," IEEE Transactions on Industrial Electronics, Vol. 56, No. 4, 986-990, 2009.
7. Li, L. and D. Uttamchandani, "A microwave dielectric biosensor based on suspended distributed MEMS transmission lines," IEEE Sensors Journal, Vol. 9, No. 12, 1825-1830, Dec., 2009.