ABSTRA CT Software automated genomic engineering (SAGE) enables arbitrary genetic modification of bacteria on a fluidic platform that implements the multiplex automated genomic engineering (MAGE) process [1]. Electrowetting-ondielectric (EWD) digital microfluidics is well suited for SAGE because of its inherent reconfigurability, small reagent volumes, and parallel processing capability [2]. We report on the first demonstration of bulk cell transformation of E. coli by an electroporation device integrated with an EWD microfluidics system, which achieved up to 9.8% transformation efficiency (evaluated as the ratio of transformed cells to survived cells) while maintaining fluid transport capability. Toward the goal of enabling efficient MAGE cycling with real time feedback control, monitoring of cell recovery and growth was implemented via reflectance spectroscopy with a limit of detection of about 10 cells/ml. Furthermore, simulated MAGE cycles showed that bacteria remained viable for at least 90 cycles (27 days) on-chip.

L'invention porte sur un procede, qui consiste en la reception d'un signal de tension de sortie produit par une alimentation superposant un signal d'excitation sur le signal de tension de sortie afin de produire un signal superpose ; la connexion du signal superpose a une electrode dans un actionneur de gouttelettes ; la suppression du signal de tension de sortie lors de la detection d'une impedance de l'electrode ; et la mesure de l'impedance de l'electrode produite par le signal d'excitation, l'impedance indiquant une presence de liquide au niveau de l'electrode.

The feasibility of implementing pyrosequencing chemistry within droplets using electrowetting-based digital microfluidics is reported. An array of electrodes patterned on a printed-circuit board was used to control the formation, transportation, merging, mixing, and splitting of submicroliter-sized droplets contained within an oil-filled chamber. A three-enzyme pyrosequencing protocol was implemented in which individual droplets contained enzymes, deoxyribonucleotide triphosphates (dNTPs), and DNA templates. The DNA templates were anchored to magnetic beads which enabled them to be thoroughly washed between nucleotide additions. Reagents and protocols were optimized to maximize signal over background, linearity of response, cycle efficiency, and wash efficiency. As an initial demonstration of feasibility, a portion of a 229 bp Candida parapsilosis template was sequenced using both a de novo protocol and a resequencing protocol. The resequencing protocol generated over 60 bp of sequence with 100% sequence accuracy based on raw pyrogram levels. Excellent linearity was observed for all of the homopolymers (two, three, or four nucleotides) contained in the C. parapsilosis sequence. With improvements in microfluidic design it is expected that longer reads, higher throughput, and improved process integration (i.e., "sample-to-sequence" capability) could eventually be achieved using this low-cost platform.

Three innovations address the needs of the medical world with regard to microfluidic manipulation and testing of physiological samples in ways that can benefit point-of-care needs for patients such as premature infants, for which drawing of blood for continuous tests can be life-threatening in their own right, and for expedited results. A chip with sample injection elements, reservoirs (and waste), droplet formation structures, fluidic pathways, mixing areas, and optical detection sites, was fabricated to test the various components of the microfluidic platform, both individually and in integrated fashion. The droplet control system permits a user to control droplet microactuator system functions, such as droplet operations and detector operations. Also, the programming system allows a user to develop software routines for controlling droplet microactuator system functions, such as droplet operations and detector operations. A chip is incorporated into the system with a controller, a detector, input and output devices, and software. A novel filler fluid formulation is used for the transport of droplets with high protein concentrations. Novel assemblies for detection of photons from an on-chip droplet are present, as well as novel systems for conducting various assays, such as immunoassays and PCR (polymerase chain reaction). The lab-on-a-chip (a.k.a., lab-on-a-printed-circuit board) processes physiological samples and comprises a system for automated, multi-analyte measurements using sub-microliter samples of human serum. The invention also relates to a diagnostic chip and system including the chip that performs many of the routine operations of a central labbased chemistry analyzer, integrating, for example, colorimetric assays (e.g., for proteins), chemiluminescence/fluorescence assays (e.g., for enzymes, electrolytes, and gases), and/or conductometric assays (e.g., for hematocrit on plasma and whole blood) on a single chip platform.

Advanced MaterialsVolume 21, Issue 35 Cover Picture Artificial Vasculature: Rapid Fabrication of Bio-inspired 3D Microfluidic Vascular Networks (Adv. Mater. 35/2009) Jen-Huang Huang, Jen-Huang Huang Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorJeongyun Kim, Jeongyun Kim Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorNitin Agrawal, Nitin Agrawal Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorArjun P. Sudarsan, Arjun P. Sudarsan Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorJoseph E. Maxim, Joseph E. Maxim National Center for Electron Beam Research, Texas A&M University College Station, TX 77845 (USA)Search for more papers by this authorArul Jayaraman, Corresponding Author Arul Jayaraman arulj@tamu.edu Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA) Department of Biomedical Engineering, Texas A&M University College Station TX 77843 (USA)Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA).Search for more papers by this authorVictor M. Ugaz, Corresponding Author Victor M. Ugaz ugaz@tamu.edu Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA).Search for more papers by this author Jen-Huang Huang, Jen-Huang Huang Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorJeongyun Kim, Jeongyun Kim Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorNitin Agrawal, Nitin Agrawal Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorArjun P. Sudarsan, Arjun P. Sudarsan Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Search for more papers by this authorJoseph E. Maxim, Joseph E. Maxim National Center for Electron Beam Research, Texas A&M University College Station, TX 77845 (USA)Search for more papers by this authorArul Jayaraman, Corresponding Author Arul Jayaraman arulj@tamu.edu Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA) Department of Biomedical Engineering, Texas A&M University College Station TX 77843 (USA)Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA).Search for more papers by this authorVictor M. Ugaz, Corresponding Author Victor M. Ugaz ugaz@tamu.edu Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA)Artie McFerrin Department of Chemical Engineering, Texas A&M University College Station, TX 77843 (USA).Search for more papers by this author First published: 15 September 2009 https://doi.org/10.1002/adma.200990132AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract The cover depicts a 3D microchannel network embedded inside an acrylic polymer substrate. The network is created using an electrostatic discharge method that instantaneously vaporizes and fractures the substrate, leaving behind a tree-like fractal arrangement of microchannels bearing a remarkable similarity to naturally occurring vasculature. The ability to rapidly construct microchannel networks incorporating a wide range of diameters (∼10–500 µm) may help enable production of organ-sized engineered tissue scaffolds containing embedded vasculature, as reported by Arul Jayaraman, Victor Ugaz, and co-workers on p. 3567. Volume21, Issue35September 18, 2009 RelatedInformation

A new method to embed branched 3D microvascular fluidic networks inside plastic substrates by harnessing electrostatic discharge phenomena is introduced. This nearly instantaneous process reproducibly generates highly branched tree-like microchannel architectures that bear remarkable similarity to naturally occurring vasculature. This method can be applied to a variety of polymers, and may help enable production of organ-sized tissue scaffolds containing embedded vasculature.