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Microfluidic Analogue of the 4-Roll Mill



Steven D. Hudson, Frederick R. Phelan Jr., Matthew D. Handler, J Cabral, Kalman D. Migler, Eric J. Amis


Microfluidic technology promises to revolutionize analytical (bio)chemistry, because molecular separations are faster, less expensive and more efficient than in traditional large scale equipment. Materials and complex-fluid sciences can likewise benefit, becuase flow conditions can be controlled precisely, and microscopic probes are compatible with the technology. Here we report the development of a versatile instrument for this purpose: a microfluidic trap (cf. an optical trap) that simulates the function of a four-roll mill, a rheological tool with adjustable flow type and rate, characteristics which are measured here by micro-particle-image-velocimetry (υPIV). This new device has two important advantages over the traditional machine: its small size is amenable to high-resolution microscopic measurements and manipulations (e.g., of single molecules, nanotubes, cells, particles and drops), and it is capable of a wider range of flow types, including simple shear. This and similar devices may be used to promote and direct the assembly and reaction of suspended particles and molecules.


4-roll mill, microfluidics, particle image velocimetry, rheology


Hudson, S. , Phelan, F. , Handler, M. , Cabral, J. , Migler, K. and Amis, E. (2004), Microfluidic Analogue of the 4-Roll Mill, Nature, [online], (Accessed April 24, 2024)
Created January 1, 2004, Updated February 17, 2017