Lab on a Chip Blog

Hydrocyclones are widely used in industries such as petrochemicals and mining for the separation of particulates from fluids at the macro- and mesoscale.  This is the first report of microscale hydrocyclone, tested on polystyrene microbeads suspended in PBS, providing continuous separation with exceptional flow rates and without clogging.  Microfluidic applications potentially include chemical analysis, materials research, point-of-care and blood sample preparation.

Microfluidic device based on a micro-hydrocyclone for particle–liquid separation
P. Bhardwaj, P. Bagdi and A. K. Sen
DOI: 10.1039/C1LC20606K

Cyclic olefin copolymer has been used to create a whole microfluidic device through microinjection moulding with the aim of bridging the gap between lab techniques and mass production of lab on a chip devices.  The team that successfully developed the platform have also come up with a dimensionless number μ_f to provide an insight into the physics of microinjection moulding.

Sustainable fabrication of micro-structured lab-on-a-chip
Hwa Jin Oh, Jae Hong Park, Seok Jae Lee, Byeong Il Kim, Young Seok Song and Jae Ryoun Youn
DOI: 10.1039/C1LC20441F

Broadband cavity-enhanced absorption spectroscopy has been used to increase the effective optical pathlengths in optical detection applied to microfluidic systems.  The BBCEAS method was capable of in situ analyte detection quickly (273 Hz/3.66 ms acquisition time) and with high sensitivity (α_min < 10⁻² cm⁻¹).

Broadband cavity-enhanced absorption spectroscopy for real time, in situ spectral analysis of microfluidic droplets
Simon R. T. Neil, Cathy M. Rushworth, Claire Vallance and Stuart R. Mackenzie
DOI: 10.1039/C1LC20854C

The production of clinical-scale quantities of droplet emulsions for in vivo therapy uses, such as gas embolotherapy, has been achieved by researchers from the universities of California and North Carolina.  Highly monodisperse liquid perfluoropentane droplets in the 3–6 μm range necessary for clinical phase-change droplets were produced at rates exceeding 10⁵ droplets per second.

High-speed, clinical-scale microfluidic generation of stable phase-change droplets for gas embolotherapy
David Bardin, Thomas D. Martz, Paul S. Sheeran, Roger Shih, Paul A. Dayton and Abraham P. Lee
DOI: 10.1039/C1LC20615J

The power generated by streaming potential from multiphase flow has been improved by the use of two phase flow in a microscale system.  A two phase microfluidic system, which converts mechanical energy to electrical energy, was devised and the addition of bubbles to the device produced a significant increase in the power and energy conversion over a single phase system.

Strong enhancement of streaming current power by application of two phase flow
Yanbo Xie, John D. Sherwood, Lingling Shui, Albert van den Berg and Jan C. T. Eijkel
DOI: 10.1039/C1LC20423H