3. Background Microfluidic Devices serve many purposes Many advantages to this technology Limited by throughput and detection methodology
4. Literature Reviews High-throughput Lens-Free Imaging and Characterization of a Heterogeneous Cell Solution Polymer Lab-on-a-Chip System with Electrical Detection
5. High-throughput Lens-Free Imaging and Characterization of a Heterogeneous Cell Solution Goal: Replace Flow Cytometry with microfluidic detection device Built off of previous work (LUCAS) Focus on decision algorithm
6. Experiment Imaged polystyrene beads and a variety of cells No external fluid flow during imaging Depth of field was 4 mm Area of field was 10 cm2 “White” light source used to generate cell shadow images
7. Results Algorithm is limited by detection of overlapping cells and plane gaps Proven detection and separate characterization of three micro particles Methods developed to characterize undetectable cells
8. Polymer Lab-on-a-Chip System with Electrical Detection Goal: Present new materials and methods for Lab-on-a-chip devices Supports the use of PEEK for fabrication Demonstrates CCD (C4D) detection method Developed “MinCE”
9. Experiment Food and beverage analysis Biological analysis Medical analysis DNA applications
10. Results Successful in all experiments as a “proof of concept” Demonstrated advantages to using PEEK Proven use of CCD for DNA analysis
11. Conclusion New material and detection methods Expanded applications for devices Research shows promise for breaking limitations
12. References Ting-Wei Su, SungkyuSeo, Anthony Erlinger, AydoganOzcan, "High-Throughput Lensfree Imaging and Characterization of a Heterogeneous Cell Solution On a Chip", Biotechnology and Bioengineering 102 (2009) 856-868 Holger Muhlberger, Wonhee Hwang, Andreas E. Guber, Volker Saile, Werner Hoffmann, "Polymer Lab-on-a-Chip System with Electrical Detection", IEEE Sensors Journal, 8 (2008) 572-579
Purposes:-Point-of-care Medical Applications-Cell characterization-Disease Detection-Biological SeparationAdvantages:-Cost effective in a large variety of circumstances-Can operate with minimal support (all on-chip)-High surface-area-to-volume ration (catalysis)Limitations:-Field of View problems for detection-Usually require fluorescence-Decision Algorithms could be improved
The proposed detection method was faster and cheaper than flow cytometry for characterizing micro particles.LUCAS = Lensless, Ultra-wide Cell Monitoring Array platform based on Shadow Imaging
Equation was developed for characterizing overlapping cells, which wasn’t a problem below 50,000 cells/second flow. Plane gaps between cells were required to be 100 micrometer or greater.Proven for both Homogeneous mixtures of different sizes and heterogeneous mixtures.Methods developed include: Surface Chemistry, Dielectric Micro Bead, and Fluorescent particle labeling
PEEK = Polyether Ether Ketone. Throughout the paper, they talk about the advantages and disadvantages of using PEEK, including the development of a new bonding process to overcome disadvantages. C4D = Capacitively Coupled Contactless Conductivity Measurements, which uses a signaling and detection electrode.MinCE = Completely Minimized Capillary Electrophoresis Device encompassing entire experimental apparatus in hand-held form.
Food and Beverage – Characterized organic acids in wine and saccharides in fruit juices.Biological Analysis – Detection of 13 amino acids in acidic media.Medical Analysis – Detection of Lithium levels in blood, which Li+ is used as a treatment for manic-depressives.DNA Applications – Two separate DNA fragments were detected in electrophoresis gel medium.
The use of PEEK, higher through-put designs, complex detection algorithms, and electrical detection methods opens the door for expanded applications. Applications include: DNA detection, Biological Analysis, Point-of-care Medical Analysis, and Food/Beverage Analysis to name a few.The literature shows that researchers are overstepping the limiting factors of microdevices. Expanded through-put and more complex detection methods are developing to create the next generation of microdevices.