Suspended Microchannel Resonators

Particles are weighed in real-time with the suspended microchannel resonator (SMR) as they flow through a hollow cantilever. In addition to weighing particles with femtogram precision, the SMR can also measure mass density with a resolution of 10-4 g/mL. This is possible since the microchannel resonant frequency is determined by the difference in mass of the particle with respect to that of the displaced fluid. Thus, the particle's density is determined by measuring its mass in two fluids of different densities.

The SMR can measure the growth of single cells as well as the absorption of biomolecules to microchannel walls. Scaling the current SMR design by ten-fold will result in a thousand-fold improvement in mass resolution (attogram) and thereby enable single viruses to be weighed with high precision.

T.P. Burg, M.Godin, S.M. Knudsen, W. Shen, G. Carlson, J.S. Foster, K. Babcock, and S.R. Manalis. Weighing of Biomolecules, Single Cells, and Single Nanoparticles in Fluid. Nature, 446 1066 (2007). Download PDF. See also News & Views.

T.P. Burg, J.E. Sader, S.R. Manalis. Nonmonotonic Energy Dissipation in Microfluidic Resonators. Physical Review Letters (2009). Download PDF.

J.E. Sader, T.P. Burg, S.R. Manalis. Energy Dissipation in Microfluidic Beam Resonators. Journal of Fluid Mechanics (2010). Download PDF.

J. Lee, W. Shen, K. Payer, T.P. Burg , S.R. Manalis. Toward attogram mass measurements in solution with suspended nanochannel resonators, Nano Letters (2010). Download PDF.

S. Olcum, N. Cermak, S.C. Wasserman, K.S. Christine, H. Atsumi, K.R. Payer, W. Shen , J. Lee, A.M. Belcher, S.N. Bhatia, S.R. Manalis. Weighing nanoparticles in solution at the attogram scale, Proceedings of the National Academy of Sciences (2014). Download PDF and Suppl. Info. See also MIT News.