Showing papers on "Biochip published in 2012"
TL;DR: A droplet-routing method that avoids cross-contamination in the optimization of droplet flow paths and targets disjoint droplet routes and minimizes the number of cells used for droplet routing is proposed.
Abstract: Recent advances in digital microfluidics have enabled droplet-based biochip devices for DNA sequencing, immunoassays, clinical chemistry, and protein crystallization. Since cross-contamination between droplets of different biomolecules can lead to erroneous outcomes for bioassays, the avoidance of cross-contamination during droplet routing is a key design challenge for biochips. We propose a droplet-routing method that avoids cross-contamination in the optimization of droplet flow paths. The proposed approach targets disjoint droplet routes and synchronizes wash-droplet routing with functional droplet routing, in order to reduce the duration of droplet routing while avoiding the cross-contamination between different droplet routes. In order to avoid cross-contamination between successive routing steps, an optimization technique is used to minimize the number of wash operations that must be used between successive routing steps. Two real-life biochemical applications are used to evaluate the proposed droplet-routing methods.
100 citations
TL;DR: It is demonstrated that a common laboratory filter paper uniformly adsorbed with biofunctionalized plasmonic nanostructures can serve as a highly sensitive transduction platform for rapid detection of trace bioanalytes in physiological fluids.
Abstract: We demonstrate that a common laboratory filter paper uniformly adsorbed with biofunctionalized plasmonic nanostructures can serve as a highly sensitive transduction platform for rapid detection of trace bioanalytes in physiological fluids. In particular, we demonstrate that bioplasmonic paper enables rapid urinalysis for the detection of kidney cancer biomarkers in artificial urine down to a concentration of 10 ng/mL. Compared to conventional rigid substrates, bioplasmonic paper offers numerous advantages such as high specific surface area (resulting in large dynamic range), excellent wicking properties (naturally microfluidic), mechanical flexibility, compatibility with conventional printing approaches (enabling multiplexed detection and multimarker biochips), and significant cost reduction.
94 citations
07 Oct 2012
TL;DR: This paper proposes a top-down architectural synthesis methodology for the flow-based biochips, in which the flow of liquid is manipulated using integrated microvalves, and synthesizes architectures for real-life applications as well as synthetic benchmarks.
Abstract: Microfluidic biochips are replacing the conventional biochemical analyzers and are able to integrate the necessary functions for biochemical analysis on-chip. In this paper we are interested in flow-based biochips, in which the flow of liquid is manipulated using integrated microvalves. By combining several microvalves, more complex units, such as micropumps, switches, mixers, and multiplexers, can be built. The manufacturing technology, soft lithography, used for the flow-based biochips is advancing faster than Moore's law, resulting in increased architectural complexity. However, the designers are still using full-custom and bottom-up, manual techniques in order to design and implement these chips. As the chips become larger and the applications become more complex, the manual methodologies will not scale, becoming highly inadequate. Therefore, for the first time to our knowledge,we propose a top-down architectural synthesis methodology for the flow-based biochips. Starting from a given biochemical application and a microfluidic component library, we are interested in synthesizing a biochip architecture, i.e., performing component allocation from the library based on the biochemical application, generating the biochip schematic (netlist) and then performing physical synthesis (deciding the placement of the microfluidic components on the chip and performing routing of the microfluidic channels), such that the application completion time is minimized. We evaluate our proposed approach by synthesizing architectures for real-life applications as well as synthetic benchmarks.
77 citations
07 Oct 2012
TL;DR: It is shown that a virtual topology, which constrains the allowable locations of assay operations such as mixing, dilution, sensing, etc., in lieu of traditional placement, can significantly speed up the synthesis process without significantly lengthening assay execution time.
Abstract: We introduce an online synthesis flow for digital microfluidic biochips, which will enable real-time response to errors and control flow. The objective of this flow is to facilitate fast assay synthesis while minimally compromising the quality of results. In particular, we show that a virtual topology, which constrains the allowable locations of assay operations such as mixing, dilution, sensing, etc., in lieu of traditional placement, can significantly speed up the synthesis process without significantly lengthening assay execution time.
60 citations
TL;DR: Current aspects in cell array technology with emphasis on microbial sensor arrays are reviewed, various techniques for patterning live cells on solid surfaces are considered, different array-based applications and devices are described, and recent efforts for live cell storage are highlighted.
59 citations
TL;DR: The capacity of the biochip to study biological processes is demonstrated by applying the method to explore the enzymatic activity of the T7 bacteriophage exonuclease by shedding new light on its behaviour that had only been examined in bulk assays previously.
Abstract: Tethered particle motion (TPM) monitors the variations in the effective length of a single DNA molecule by tracking the Brownian motion of a bead tethered to a support by the DNA molecule. Providing information about DNA conformations in real time, this technique enables a refined characterization of DNA–protein interactions. To increase the output of this powerful but time-consuming single-molecule assay, we have developed a biochip for the simultaneous acquisition of data from more than 500 single DNA molecules. The controlled positioning of individual DNA molecules is achieved by self-assembly on nanoscale arrays fabricated through a standard microcontact printing method. We demonstrate the capacity of our biochip to study biological processes by applying our method to explore the enzymatic activity of the T7 bacteriophage exonuclease. Our single molecule observations shed new light on its behaviour that had only been examined in bulk assays previously and, more specifically, on its processivity.
58 citations
12 Mar 2012
TL;DR: A “physical-aware” system reconfiguration technique that uses sensor data at checkpoints to dynamically reconfigure the biochip, thereby deriving new schedules, module placement, and droplet routing pathways, with minimum impact on the time-to-response.
Abstract: Droplet-based "digital" microfluidics technology has now come of age and software-controlled biochips for healthcare applications are starting to emerge. However, today's digital microfluidic biochips suffer from the drawback that there is no feedback to the control software from the underlying hardware platform. Due to the lack of precision inherent in biochemical experiments, errors are likely during droplet manipulation, but error recovery based on the repetition of experiments leads to wastage of expensive reagents and hard-to-prepare samples. By exploiting recent advances in the integration of optical detectors (sensors) in a digital microfluidics biochip, we present a "physical-aware" system reconfiguration technique that uses sensor data at checkpoints to dynamically reconfigure the biochip. A re-synthesis technique is used to recompute electrode-actuation sequences, thereby deriving new schedules, module placement, and droplet routing pathways, with minimum impact on the time-to-response.
58 citations
TL;DR: The investigation demonstrated that combining the transcriptomic and proteomic analyses obtained from a cell “on chip” culture would provide a pertinent new tool in the mechanistic interpretation of cellular mechanisms for predicting kidney cell toxicity and renal clearance in vitro.
Abstract: We have evaluated the influence of the microfluidic environment on renal cell functionality. For that purpose, we performed a time lapse transcriptomic and proteomic analysis in which we compared gene and protein expressions of Madin–Darby canine kidney cells after 24 h and 96 h of culture in both microfluidic biochips and plates. The transcriptomic and proteomic integration revealed that the ion transporters involved in calcium, phosphate, and sodium homoeostasis and several genes involved in H+ transporters and pH regulation were up-regulated in microfluidic biochips. Concerning drug metabolism, we found Phase I (CYP P450), Phase II enzymes (GST), various multidrug resistance genes (MRP), and Phase III transporters (SLC) were also up-regulated in the biochips. Furthermore, the study shows that those inductions were correlated with the induction of the Ahr and Nrf-2 dependent pathways, which results in a global cytoprotective response induced by the microenvironment. However, there was no apoptosis situation or cell death in the biochips. Microfluidic biochips may thus provide an important insight into exploring xenobiotic injury and transport modifications in this type of bioartificial microfluidic kidney. Finally, the investigation demonstrated that combining the transcriptomic and proteomic analyses obtained from a cell “on chip” culture would provide a pertinent new tool in the mechanistic interpretation of cellular mechanisms for predicting kidney cell toxicity and renal clearance in vitro. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2012
58 citations
TL;DR: A diffusion-restriction model was applied to a miniaturized biochip nanovolume reactor to accurately characterize DNA hybridization events that contribute to shifts in both charge transfer resistance and diffusional resistance, and this highly functional microfluidic biosensor enables the detection of ssDNA targets selectively.
57 citations
TL;DR: It is shown that a silicon dioxide grid can be modified into a biochip to combine in situ protein synthesis, assembly and imaging at the nanoscale and this biochip could be used to create spatial patterns of proteins assembled on surfaces.
Abstract: Biologically active complexes such as ribosomes and bacteriophages are formed through the self-assembly of proteins and nucleic acids. Recapitulating these biological self-assembly processes in a cell-free environment offers a way to develop synthetic biodevices. To visualize and understand the assembly process, a platform is required that enables simultaneous synthesis, assembly and imaging at the nanoscale. Here, we show that a silicon dioxide grid, used to support samples in transmission electron microscopy, can be modified into a biochip to combine in situ protein synthesis, assembly and imaging. Light is used to pattern the biochip surface with genes that encode specific proteins, and antibody traps that bind and assemble the nascent proteins. Using transmission electron microscopy imaging we show that protein nanotubes synthesized on the biochip surface in the presence of antibody traps efficiently assembled on these traps, but pre-assembled nanotubes were not effectively captured. Moreover, synthesis of green fluorescent protein from its immobilized gene generated a gradient of captured proteins decreasing in concentration away from the gene source. This biochip could be used to create spatial patterns of proteins assembled on surfaces.
55 citations
TL;DR: The one-step, cost-effective DNA-linking method on non-modified polymers significantly simplifies microarray fabrication procedures and permits great flexibility to plastic material selection, thus making it convenient to integrate microarrays into plastic microfluidic systems.
Abstract: DNA microarrays have become one of the most powerful tools in the field of genomics and medical diagnosis. Recently, there has been increased interest in combining microfluidics with microarrays since this approach offers advantages in terms of portability, reduced analysis time, low consumption of reagents, and increased system integration. Polymers are widely used for microfluidic systems, but fabrication of microarrays on such materials often requires complicated chemical surface modifications, which hinders the integration of microarrays into microfluidic systems. In this paper, we demonstrate that simple UV irradiation can be used to directly immobilize poly(T)poly(C)-tagged DNA oligonucleotide probes on many different types of plastics without any surface modification. On average, five- and fourfold improvement in immobilization and hybridization efficiency have been achieved compared to surface-modified slides with aminated DNA probes. Moreover, the TC tag only costs 30% of the commonly used amino group modifications. Using this microarray fabrication technique, a portable cyclic olefin copolymer biochip containing eight individually addressable microfluidic channels was developed and used for rapid and parallel identification of Avian Influenza Virus by DNA hybridization. The one-step, cost-effective DNA-linking method on non-modified polymers significantly simplifies microarray fabrication procedures and permits great flexibility to plastic material selection, thus making it convenient to integrate microarrays into plastic microfluidic systems.
TL;DR: DEP is useful in biosensor and biochips platforms for enhancing antibody capture efficiency in both flow-through and non-flow-through microdevices, and has the potential to improve the detection of bacterial cells.
Abstract: This paper reviews the functions of dielectrophoresis (DEP) that have been applied to biosensor and biochip platforms for bacteria detection, including concentration of bacterial cells from continuous flows, separation of target bacterial cells from non-target cells, as well as the enhancement of antibody capture efficiency on biosensor and biochip surfaces. DEP could provide effective concentration and separation simultaneously in well-designed microfluidic biosensor and biochip systems. The integration of DEP with a detection system allows the integration of sample preparation and enrichment steps with detection, which has the potential to eliminate the traditionally used time-consuming culture-based enrichment steps and other multiple off-chip sample preparation steps. DEP is also useful in biosensor and biochips platforms for enhancing antibody capture efficiency in both flow-through and non-flow-through microdevices. The enhanced antibody capture efficiency could allow the sensor capture more cells a...
01 Oct 2012
TL;DR: An open source DMFB synthesis framework is introduced and a common interface is introduced to encourage collaboration between researchers working in the area, and a number of high-quality 2D and 3D debugging tools are presented that provide graphical output for each stage of synthesis.
Abstract: Synthesis of digital microfluidic biochips (DMFBs) is a crucial to the advancement and realization of miniaturized, automated, programmable biochemistry solutions; synthesis is performed in three steps: scheduling, placement and routing. In principle, algorithms for specific steps should be interchangeable with one another; however, different research groups typically develop algorithms for each step in isolation from one another. Thus, it is difficult to compare algorithms against one another, or to determine which algorithms for different steps share synergies. We introduce an open source DMFB synthesis framework to encourage collaboration between researchers working in the area. We introduce a common interface and describe the internal data structures that must be updated to ensure that the interfaces are adhered to. We also present and describe a number of high-quality 2D and 3D debugging tools that provide graphical output for each stage of synthesis.
TL;DR: The ability of RTgill-W1 biochips to maintain monolayer integrity without media replenishments for 78weeks, combined with their chemical sensitivity and rapid response time, make them excellent candidates for use in low cost, maintenance-free field-portable biosensors.
Proceedings Article•
25 Apr 2012
TL;DR: In this paper, the authors proposed an online synthesis strategy to determine the appropriate recovery actions at the moment when faults are detected, which can capture both time and space-redundant and space redundant recovery operations.
Abstract: Microfluidic-based biochips are replacing the conventional biochemical analyzers, and are able to integrate on-chip all the necessary functions for biochemical analysis using microfluidics. The digital microfluidic biochips are based on the manipulation of liquids not as a continuous flow, but as discrete droplets. Researchers have presented approaches for the synthesis of digital microfluidic biochips, which, starting from a biochemical application and a given biochip architecture, determine the allocation, resource binding, scheduling, placement and routing of the operations in the application. The droplet volumes can vary erroneously due to parametric faults, thus impacting negatively the correctness of the application. Researchers have proposed approaches that synthesize offline predetermined recovery subroutines, which are activated online when errors occur. In this paper, we propose an online synthesis strategy, which determines the appropriate recovery actions at the moment when faults are detected. We have also proposed a biochemical application model which can capture both time-redundant and space-redundant recovery operations. Experiments performed on three real-life case studies show that, by taking into account the biochip configuration when errors occur, our online synthesis is able to reduce the application times.
TL;DR: The recently developed "metabolomics-on-a-chip" approach with metabolic flux analysis is combined to model the metabolic network of the hepatoma HepG2/C3A cell line and to infer the distribution of intracellular metabolic fluxes in standard Petri dishes and microfluidic biochips.
Abstract: In vitro microfluidic systems are increasingly used as an alternative to standard Petri dishes in bioengineering and metabolomic investigations, as they are expected to provide cellular environments close to the in vivo conditions. In this work, we combined the recently developed "metabolomics-on-a-chip" approach with metabolic flux analysis to model the metabolic network of the hepatoma HepG2/C3A cell line and to infer the distribution of intracellular metabolic fluxes in standard Petri dishes and microfluidic biochips. A high pyruvate reduction to lactate was observed in both systems, suggesting that the cells operate in oxygen-limited environments. Our results also indicate that HepG2/C3A cells in the biochip are characterized by a higher consumption rate of oxygen, presumably due to a higher oxygenation rate in the microfluidic environment. This leads to a higher entry of the ultimate glycolytic product, acetyl-CoA, into the Krebs cycle. These findings are supported by the transcriptional activity of HepG2/C3A cells in both systems since we observed that genes regulated by a HIF-1 (hypoxia-regulated factor-1) transcriptional factor were over expressed under the Petri conditions, but to a lesser extent in the biochip.
TL;DR: A simple and effective polydiacetylene-based, label-free multiplex DNA chip for the detection of various pathogenic microorganisms that was effective in detecting multiple pathogenic bacteria easily and accurately without rigorous purification, amplification, and labeling of their genetic components.
TL;DR: The novel method established by a specially designed giant magnetoresistive (GMR) biochip combined with magnetic nanoclusters, PCR and line probe assay has great potential application in clinical HBV genotyping diagnosis, and can be easily extended to other biomedical applications based on molecular recognition.
Abstract: Genotyping of human hepatitis B virus (HBV) can be used to direct clinically effective therapeutic drug-selection. Herein we report that a quick genotyping method for human HBV was established by a specially designed giant magnetoresistive (GMR) biochip combined with magnetic nanoclusters (MNCs), PCR and line probe assay. Magnetic nanoclusters of around 180 nm in diameter were prepared and modified with streptavidin, and resultant streptavidin-modified magnetic nanoclusters were used for capturing biotin-labeled hybrid products on the detection interface of the sensor. The gene fragments of HBV’s B and C gene types were obtained by PCR based on a template of B- and C-type plasmids. After gene fragments were hybridized with captured probes, streptavidin-modified magnetic nanoclusters could bind with biotin-conjugated gene fragments, and the resultant hydride products could be quickly detected and distinguished by the GMR sensor, with a detection sensitivity of 200 IU mL−1 target HBV DNA molecules. The novel method has great potential application in clinical HBV genotyping diagnosis, and can be easily extended to other biomedical applications based on molecular recognition.
TL;DR: The work presented here shows the application of L-DPN for the generation of arrays of the ligand 2,4-dinitrophenyl[1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N] onto glass surfaces as a model system for detection of allergen-specific Immunoglobin E (IgE) antibodies and for mast cell activation profiling.
Abstract: Multiple-allergen testing for high throughput and high sensitivity requires the development of miniaturized immunoassays that allow for a large test area and require only a small volume of the test analyte, which is often available only in limited amounts. Developing such miniaturized biochips containing arrays of test allergens needs application of a technique able to deposit molecules at high resolution and speed while preserving its functionality. Lipid dip-pen nanolithography (L-DPN) is an ideal technique to create such biologically active surfaces, and it has already been successfully applied for the direct, nanoscale deposition of functional proteins, as well as for the fabrication of biochemical templates for selective adsorption. The work presented here shows the application of L-DPN for the generation of arrays of the ligand 2,4-dinitrophenyl[1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine-N-[6-[(2,4-dinitrophenyl)amino]hexanoyl] (DNP)] onto glass surfaces as a model system for detection of allergen-specific Immunoglobin E (IgE) antibodies and for mast cell activation profiling.
TL;DR: A combination of domain decomposition and balanced truncation model reduction which allows explicit error bounds for the error between the reduced order and the fine-scale optimization problem gives rise to a significant reduction of the problem size while maintaining the accuracy of the approximation.
TL;DR: In this article, a low pressure plasma polymerized acrylic acid (exposing COOH groups) thin coating was applied to a low-density microarray biochip for the efficient grafting of suitable NH2 terminated probes able to match complementary DNA oligonucleotides of Listeria monocytogenes by means of a novel hybridization protocol and a commercial simple and low-cost colorimetric detection method compatible with POC applications.
Abstract: The rapid detection of enteropathogens with high sensitivity and selectivity continues to be a significant challenge, especially in order to transfer laboratory analyses to the Point-Of‐Care (POC) by developing simple and reliable diagnostic kits. Bacterial infections are already detected, in analytical labs, by means of high-density microarray biochips based both on RNA/DNA fragments and antibodies as probes and antigens receptors, respectively, immobilized on the chip surface. Many efforts to obtain a high efficiency of the surface chemical properties for a stable probes grafting in order to avoid unspecificity or non-selectivity of the bio-recognition are still under way. The aim of this work is to show the advantages of applying a low pressure plasma polymerized acrylic acid (exposing COOH groups) thin coating to a low-density microarray biochip for the efficient grafting of suitable NH2 terminated probes able to match complementary DNA oligonucleotides of Listeria monocytogenes by means of a novel hybridization protocol and a commercial simple and low-cost colorimetric detection method compatible with POC applications. The chemical properties of the obtained polyacrylic acid thin films are characterized by means of ATR FT-IR spectroscopy, XPS and contact angle (OCA) measurements. The surface density of the carboxylic functionalities is quantified by colorimetric titration with Toluidine Blue O (TBO). The optimized functional thin film is shown to provide good advantages for DNA microarray diagnostics in terms of chemical stability, density of readily accessible COOH groups and at the same time low hydrophilicity, crucial for reducing the dilution of spotted probes on the surface and thus resulting in higher and satisfying intensity of the detect signals in the microarray test.
TL;DR: An algorithm based on a Greedy Randomized Adaptive Search Procedure (GRASP) is developed and it is shown that routing-based synthesis leads to significant improvements in the application completion time compared to traditional synthesis based on virtual devices.
Abstract: Microfluidic biochips are replacing the conventional biochemical analyzers, and are able to integrate on-chip all the necessary functions for biochemical analysis. The "digital" biochips are manipulating liquids as discrete droplets on a two-dimensional array of electrodes. Basic microfluidic operations, such as mixing and dilution, are performed on the array, by routing the corresponding droplets on a series of electrodes. So far, researchers have assumed that these operations are executed on virtual rectangular devices, formed by grouping several adjacent electrodes. One drawback is that all electrodes are considered occupied during the operation execution, although the droplet uses only one electrode at a time. Moreover, the operations can actually be performed by routing the droplets on any sequence of electrodes on the microfluidic array. Hence, in this paper, we eliminate the concept of virtual devices and allow the droplets to move on the chip on any route during operation execution. Thus, the synthesis problem is transformed into a routing problem. We develop an algorithm based on a Greedy Randomized Adaptive Search Procedure (GRASP) and we show that routing-based synthesis leads to significant improvements in the application completion time compared to traditional synthesis based on virtual devices. However, the disadvantage of the routing-based approach is that it may contaminate larger areas of the biochip, when synthesizing applications containing liquids which may adsorb on the surface of the microfluidic array. We have extended the GRASP-based algorithm to consider contamination avoidance during routing-based synthesis. Several real-life examples and synthetic benchmarks are used to evaluate the proposed approaches.
TL;DR: This work proposes a DNA-based biochip suitable for cell-type analysis in a label-free manner and shows not only specific capture of primary spleen cells on protein-DNA microarray spots but also their fast and specific orthogonal release according to the antibody-DNA combinations by incorporating restriction sites in DNA.
TL;DR: A novel biochip platform for the rapid analysis/identification of nucleic acids, including DNA and microRNAs, with very high specificity is described, which promises to transform and expand routine clinical diagnostic testing and screening for genetic diseases, cancers, drug toxicology and heart disease, as well as employment in the emerging companion diagnostics market.
Abstract: This manuscript describes the use of a novel biochip platform for the rapid analysis/identification of nucleic acids, including DNA and microRNAs, with very high specificity. This approach combines a unique dynamic chemistry approach for nucleic acid testing and analysis developed by DestiNA Genomics with the STMicroelectronics In-Check platform, which comprises two microfluidic optimized and independent PCR reaction chambers, and a sequential microarray area for nucleic acid capture and identification by fluorescence. With its compact bench-top "footprint" requiring only a single technician to operate, the biochip system promises to transform and expand routine clinical diagnostic testing and screening for genetic diseases, cancers, drug toxicology and heart disease, as well as employment in the emerging companion diagnostics market.
05 Nov 2012
TL;DR: This work presents a hardware-assisted error-recovery method that relies on an error dictionary for rapid error recovery, and uses three laboratorial protocols to demonstrate that, compared to software-based methods, this method has less impact on response time, and requires simple experimental setup, and only a small amount of memory.
Abstract: A cyberphysical digital microfluidics system is an emerging technology that enables the integration of fluid-handling operations, reaction-outcome detection, and automated error recovery on a biochip The cyberphysical biochip system studied thus far suffers from the limitation of a significant increase in reaction time for error recovery We present a hardware-assisted error-recovery method that relies on an error dictionary for rapid error recovery The error-recovery procedure and dynamic resynthesis of a reaction, which is especially attractive for flash chemistry, can be implemented in real-time on a single-board microcontroller In order to store the error dictionary in the limited memory available in the low-cost microcontroller, we describe two compaction techniques We use three laboratorial protocols to demonstrate that, compared to software-based methods, the proposed dictionary-based error-recovery method has less impact on response time, and requires simple experimental setup, and only a small amount of memory
TL;DR: The integrin pathway was perturbed with the ifosfamide treatment, and the MYC proto-oncogene appeared to be a potential bridge between the integrin signaling and the anti-inflammatory response.
Journal Article•
TL;DR: Results in the presence study demonstrated that the PCR techniques and southern-hybridization on the biochip is suitable tool for monitoring the Haram component in highly processed product of soft and hard capsule.
Abstract: The study was conducted to detect the porcine DNA in pharmaceutical products in local market using polymerase chain reaction (PCR) and southern-hybridization on the biochip. A total of 113 (n=113) of hard (82 samples) and soft gel (31 samples) capsules from pharmaceutical products were purchased and tested for the presence of porcine DNA for Halal authentication. All capsules were gelatin-based purchased from local over the counter (OTC) markets. Of all samples tested, 37.2% (42/113) contained porcine DNA. While, none porcine DNA band was detected for 62.8% (71/113) of capsules tested. All samples which were positive toward porcine DNA were imported pharmaceutical products with none Halal logo. Results in the presence study demonstrated that the PCR techniques and southern-hybridization on the biochip is suitable tool for monitoring the Haram component in highly processed product of soft and hard capsule.
TL;DR: The functionality of the HepG2/C3a cells in parallelized microfluidic culture conditions was highlighted and the potential for larger in vitro toxicity studies using the IDCCM tools was illustrated.
Abstract: In this paper, we present a tool box to perform parallelized microfluidic cultures. The box was made in polycarbonate (PC) using a 24-well plate format. The microfluidic biochips were made in polydimethylsiloxane (PDMS). Two wells of the PC plate were used as inlet/outlet and fluid reservoir for one biochip. A hermetic cover was fabricated in PC to allow continuous and sterile dynamic cell cultures. Thus, the entire set up, called IDCCM for “Integrated Dynamic Cell Cultures in Microsystems” allowed the perfusion culture of 12 biochips simultaneously. To demonstrate the potential of the IDCCM box and the cell functionality, we analyzed the behaviour of HepG2/C3a liver cells. For that purpose, we have investigated the effects of the inoculated cell density and of the flow rates on the cell proliferation, glucose consumption, albumin production and the cytochrome P450-1A activity over 96 h of cultures. The results have shown that the cell proliferation and the cytochrome P450-1A activity were cell density and flow rate dependent. This led to identify a best optimized condition with HepG2/C3a at (5–7) × 105 cells/biochip (corresponding to (2.5–3.5) × 105 cells/cm2) and at a perfusion flow rate of 25 μL/min. This result highlighted the functionality of the HepG2/C3a cells in parallelized microfluidic culture conditions and illustrated the potential for larger in vitro toxicity studies using the IDCCM tools.
TL;DR: In this paper, a hybrid processing approach that uses laser micromachining (LMM) and precision glass molding (PGM) techniques to mass-produce glass-based biochips is presented.
30 Sep 2012
TL;DR: An automated design methodology for sample preparation, including architectural synthesis, layout synthesis, and dynamic error recovery is presented, and the proposed algorithm is evaluated on real-life biochemical applications to demonstrate its effectiveness and efficiency.
Abstract: Recent advances in digital microfluidic biochips have led to a promising future for miniaturized laboratories, with the associated advantages of high sensitivity and reconfigurability. As one of the front-end operations on digital microfluidic biochips, sample preparation plays an important role in biochemical assays and applications. For fast and high-throughput biochemical applications, it is critical to develop an automated design methodology for sample preparation. Prior work in this area does not provide solutions to the problem of design automation for sample preparation. Moreover, it is critical to ensure the correctness of droplets and recover from errors efficiently during sample preparation. Published work on error recovery is inefficient and impractical for sample preparation. Therefore, in this paper, we present an automated design methodology for sample preparation, including architectural synthesis, layout synthesis, and dynamic error recovery. The proposed algorithm is evaluated on real-life biochemical applications to demonstrate its effectiveness and efficiency. Compared to prior work, the proposed algorithm can achieve up to 48.39% reduction in sample preparation time.