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Lab on a Chip Industry Workshop
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August 2-3 2014 in Dalian, China
This workshop focuses on the innovative developments in Lab-on-a-Chip technology and the applications of microfluidics in diagnostics, biological, material, pharmaceutical, and environmental sciences. For more information, please visit the official webpage.
A microfluidic chip with channels that can be programmed then reset and reconfigured has been developed by scientists from France and Japan.
In recent years, scientists from across of the globe have developed a plethora of microfluidic chips to perform a variety of tasks, from PCR to cell sorting. However, a serious drawback of microfluidic technologies is that each application requires a unique arrangement of inlets, outlets and microchannels, so microfluidic chips are usually specific to one particular purpose. This, combined with the time-consuming and costly manufacturing processes required to construct microfluidic devices, makes the idea of a reprogrammable chip very attractive.
Read the full article here at Chemistry World.
Programmable and reconfigurable microfluidic chip
Raphaël Renaudot, et al.
Lab Chip, 2013, Accepted Manuscript
DOI: 10.1039/C3LC50850A, Paper
We are very pleased to announce that Lab on a Chip will once again Co-host the third EU-Korea Workshop on microfluidics, focusing on “Emerging Microfluidic Platform Technologies: From Biosciences to Applications”.
Please come along and see us at the meeting, which will be held in Postech International Centre, Pohang, Korea. The workshop takes place on October 3rd to 5th, 2013.
Meet the Editor and International speakers:
Jean-Louis Viovy, Institute Curie, France
Andreas Manz, KIST, Europe
Dongpyo Kim, Pohang, Koreas
Chris Abell, Cambridge, UK
Noo Li Jeon, Seoul, Korea
Sabeth Verpoorte, Groningen, Netherlands
Hywel Morgan, Southampton, UK
Petra Dittrich, ETH Zurich, Switzerland
Sanghyun Lee, FEMTOLAB, Korea
Samuel Sanchez, Max-Planck, Germany
Yoon Kyoung Cho, UNIST, Korea
Francois Leblanc, CEO Fluigent
Lab-on-a-Chip would like to present the most cited articles of 2010 and 2011! We would like to use this opportunity to highlight some of the excellent work that the miniaturisation community is producing right now, and to congratulate our authors on their fantastic achievements.
As of now, all of the below articles will be free for 4 weeks (until Monday 16th Sept),* so make the most of this opportunity to download the full papers!
Top 3 Cited Reviews:
- CN Baroud et. al.: Dynamics of microfluidic droplets (DOI: 10.1039/c001191f).
A critical review on the current understanding of the formation, transport and merging of drops in microfluidics. Baroud and colleagues discuss the physical ingredients that differentiate droplet microfluidics from single-phase microfluidics.
- YK Cho et. al.: Centrifugal microfluidics for biomedical applications (DOI: 10.1039/b924109d).
A critical review on the biomedical applications of centrifugal microfluidics. Cho and colleagues review current sample-to-naswer systems and the challenges that must be faced before the centrifugal platform can be used as a new diagnostic platform.
- GB Lee et. al.: Microfluidic cell culture systems for drug research (DOI: 10.1039/b921695b).
A tutorial review on microfluidic cell cultures and their use in drug research. The review covers the issues of cell immobilisation, medium pumping and gradient generation, as well as providing examples of practical applications.
Top 10 Cited Research Papers:
- GM Whitesides et. al.: Electrochemical sensing in paper-based microfluidic devices (DOI: 10.1039/b917150a).
A paper on the fabrication and performance of microfluidic paper-based sensing devices. Whitesides and colleagues demonstrated that their paper-based electrochemical devices are capable of quantifying concentrations of various analytes, including heavy metal ions and glucose.
- D Di Carlo et. al.: Sheathless inertial cell ordering for extreme throughput flow cytometry (DOI: 10.1039/b919495a).
A paper which demonstrates the use of a microfluidic device for flow-cytometry with extreme throughput. Di Carlo and colleagues demonstrated 86-97% cell counting sensitivity and specificity.
- A Ozcan et. al.: Compact, light-weight and cost-effective microscope based on lensless incoherent holography for telemedicine applications (DOI: 10.1039/c000453g).
Ozcan and colleagues demonstrate a lensless on-chip microscope weighing only approx. 46 g and dimensions smaller than 5 cm3. The microscope achieves subcellular resolution and may offer a cost-effective tool in the development of portable medicine.
- D Di Carlo et. al.: Deformability-based cell classification and enrichment using inertial microfluidics (DOI: 10.1039/c0lc00595a)
- BJ Kirby et. al.: Capture of circulating tumor cells from whole blood of prostate cancer patients using geometrically enhanced differential immunocapture (GEDI) and a prostate-specific antibody (DOI: 10.1039/b924420d)
- A Ozcan et. al.: Lensfree microscopy on a cellphone (DOI: 10.1039/c003477k)
- CF Carlborg et. al.: A packaged optical slot-waveguide ring resonator sensor array for multiplex label-free assays in labs-on-chips (DOI: 10.1039/b914183a)
- T Franke et. al.: Surface acoustic wave actuated cell sorting (SAWACS) (DOI: 10.1039/b915522h)
- JL Osborn et. al.: Microfluidics without pumps: reinventing the T-sensor and H-filter in paper networks (DOI: 10.1039/c004821f)
- LG Griffith et. al.: Perfused multiwell plate for 3D liver tissue engineering (DOI: 10.1039/b913221j)
*free through an RSC publishing personal account
Richard Crooks and colleagues, researchers at the University of Texas, Austin developed a way to locally concentrate and move analytes using internal bipolar electrodes (bypassing the need for an outside driver of fluid flow). Electrodes printed on the bottom of the microfluidic channels create controllable gates which balance the convective and electrokinetic forces acting on charged sample molecules. A single DC power supply and controller box is needed to open/close these gates to deliver analytes to different regions of the chip.
Crooks and his group have extensively investigated bipolar electrochemistry theory and in this paper demonstrate the use of bipolar electrodes to separate, enrich, and transport bands of analytes in microfluidic channels. Electric potentials applied across a channel induce an electric field within the buffer whilst conductive substrates present on the floor of the microchannel also adopt a potential between their two poles. H+ ions within the buffer are partially neutralized by electrogenerated OH- and thus regions of ion depletion appear. These depletion zones attract charged analytes from the solution to maintain the charge gradient induced by the electric field (the speed of electromigration of analytes to the depletion zone is proportional to the electric field). Bipolar electrodes on the channel bottom contain their own local field and so analytes concentrate in these areas, leading to enrichment near the electrodes.
In this work, Crooks and his team demonstrate separation and enrichment of two common fluorescent dyes: BODIPY2- and MPTS3-. The two dye bands are then directed to two separate reservoirs. In previous papers, the group focused on optimizing enrichment and achieved enrichment rates of up to 0.57 BODIPY2 1, . The current extension and integration of online separation and enrichment achieves comparable rates of enrichment, 0.11 and 0.31 fold/second for BODIPY and MPTS, respectively, while also enabling control over separating analytes of different electromobility (μep) and transporting these bands to designated areas of the device.
To create the devices presented, the group used conventional photolithography techniques to pattern gold bipolar passive electrodes (BPEs) on glass and bonded PDMS channels on top of the regions. This method can be easily multiplexed as additional BPEs can be activated to guide separated and enriched analytes to different areas of the chip.
1 R. K. Anand, E. Sheridan, D. Hlushkou, U. Tallarek and R. M. Crooks, Lab on a Chip, 2011, 11, 518-527.
Electrochemically-gated delivery of analyte bands in microfluidic devices using bipolar electrodes
Karen Scida, Eoin Sheridan and Richard M. Crooks, Lab Chip, 2013, 13, 2292-2299.
View the new videos on the Lab on a Chip YouTube site using the links below:
Repeated biopsies of tumours can be a painful and distressing procedure for cancer patients. A new biochip developed by researchers in Singapore can isolate tumour cells from blood samples, and may one day be an alternative to more invasive methods for tracking later stage cancers.
Slanted spiral microfluidics for the ultra-fast, label-free isolation of circulating tumor cells
E W Majid et al, Lab Chip, 2013, Accepted manuscript, Paper
View the new videos on the Lab on a Chip YouTube site using the links below:
Today, calling is not the only function of the cell-phone, but in some cases just a nice side function. A new function developed by Aydogan Ozcan and co-workers is the ability to perform a rapid blood analysis using your cell phone.
In a previous article the group at University of California, Los Angeles, USA, showed that a cell-phone with some add-on components can be used to test for the presence of peanuts in cookies1. In this new article, a module is demonstrated which can be used to measure characteristics of blood. Three variables which can be tested with their system are the haemoglobin content and white and red blood cell concentrations.
After connecting a base attachment to the cell phone (in this case an Android phone), three different add-on components can then be attached. Each component consists of a lens, light source and chamber for the sample. For the white blood cell count, the cells are first fluorescently labelled and placed in a chamber with known volume. Subsequently the sample is excited and the fluorescence is measured in the perpendicular direction. In case of the red blood cell count, unlabelled cells in a specific volume are optically detected using bright field illumination. For the last application, the measurement of the haemoglobin content, the absorbance of the lysed blood sample is determined, which is directly related to the concentration of haemoglobin. The user-friendly phone app allows you to choose one of the three analyses and input parameters, such as the sample dilution factor. It subsequently processes the captured images to generate the test results, which can be uploaded to a database or sent on to clinicians
Although some sample pre-processing is necessary, the blood analysis will take about 10 seconds for each image taken. The results of the cell phone module are in good agreement with a standard test, thereby making it applicable for blood analysis at point of care.
1. Ahmet F. Coskun, Justin Wong, Delaram Khodadadi et al. A personalized food allergen testing platform on a cellphone. Lab Chip, 2013, 13, 636–640
Cost-effective and rapid blood analysis on a cell-phone
Hongying Zhu, Ikbal Sencan, Justin Wong, Stoyan Dimitrov, Derek Tseng, Keita Nagashima and Aydogan Ozcan
Loes Segerink is a Post-Doctoral researcher in the BIOS Lab on a Chip group, University of Twente, The Netherlands