MSc thesis project proposal

Suspended microchannel resonators for weighting nanoparticles in liquid.

The characterization of nanoparticles with respect to their mass is a very attractive field of study with multiple applications in biology, chemistry or medicine. We are developing new sensing methods based on the fusion of resonating structures with microfluidics. Through the shift in the resonance frequency of a resonator, particles suspended in liquid can be detected with mass values down to the attogram, leading to the characterization of single bacteria [1]. This is achieved by embedding a microchannel inside a resonator and making the liquid flow through it.

Current microfluidic cantilevers involve complex microfabrication processes that prevent their widespread application. Recently, 3D printed cantilevers have been demonstrated thanks to the development of 2-photon polymerization, a 3D printing technique that allows for nanometer resolution. Nevertheless, this technology is based on polymers with poor mechanical performance. In this project, a hybrid approach will be followed consisting in the implementation of microfluidic channels with 2PP on silicon beams fabricated by standard cleanroom etching. The result will combine good mechanical characteristics provided by the silicon substrate with the design flexibility on the microfluidic part provided by the 3D printing technique.

[1] Burg, Thomas P., et al. "Weighing of biomolecules, single cells and single nanoparticles in fluid." nature 446.7139 (2007): 1066.


  • Carry out a literature review on existing devices to characterize the mass of nanoparticles, with focus on mechanical resonators.
  • Fabricate suspended silicon beams by cleanroom processing.
  • 3-D print microfluidic channels on the silicon beams by 2-photon polymerization
  • Perform vibrometry measurements to characterize the device resonance frequency and quality factor before and after printing the microchannels.
  • Test the flow of liquid through the microchannels, to detect problems like clogging or leaking.


You must be motivated to learn and apply different techniques for fabricating new devices. The project will be developed in EEMCS and 3mE Faculties.


dr. Tomás Manzaneque

Electronic Instrumentation Group

Department of Microelectronics

Last modified: 2022-10-10