A low-cost smartphone controlled portable system with accurately confined on-chip 3D electrodes for flow-through cell electroporation

In this work, we designed, fabricated and tested a disposable, flow-through amperometric sensor for free chlorine determination in water. The sensor is based on the principle of an electrochemical cell. The substrate, as well as the top microfluidic layer, is made up of a polymer material. The advantages include; (a) disposability from low cost; (b) stable operation range from three-electrode design; (c) fluidic interconnections that provide on line testing capabilities; and (d) transparent substrate which provides for future integration of on-chip optics. The sensor showed a good response and linearity in the chlorine concentration ranging from 0.3 to 1.6 ppm, which applies to common chlorination process for drinking water purification.

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Manipulation of the Phase-Amplitude Coupling Factor in Quantum Nanostructure Based Devices for On-Chip Chirp Compensation and Low-Cost Applications

10.21236/ada619855 ◽

2014 ◽

Author(s):

Frederic Grillot

Keyword(s):

Low Cost ◽

Coupling Factor ◽

Chirp Compensation ◽

On Chip ◽

Phase Amplitude

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Design and Manufacturing of a Disposable, Cyclo-Olefin Copolymer, Microfluidic Device for a Biosensor †

Sensors ◽

10.3390/s19051178 ◽

2019 ◽

Vol 19 (5) ◽

pp. 1178 ◽

Cited By ~ 2

Author(s):

Jorge Prada ◽

Christina Cordes ◽

Carsten Harms ◽

Walter Lang

Keyword(s):

Microfluidic Device ◽

Heating Temperature ◽

Low Cost ◽

Reaction Chamber ◽

Microfluidic System ◽

Heating Process ◽

Design And Manufacturing ◽

On Chip ◽

Working Parameters ◽

Auto Fluorescence

This contribution outlines the design and manufacturing of a microfluidic device implemented as a biosensor for retrieval and detection of bacteria RNA. The device is fully made of Cyclo-Olefin Copolymer (COC), which features low auto-fluorescence, biocompatibility and manufacturability by hot-embossing. The RNA retrieval was carried on after bacteria heat-lysis by an on-chip micro-heater, whose function was characterized at different working parameters. Carbon resistive temperature sensors were tested, characterized and printed on the biochip sealing film to monitor the heating process. Off-chip and on-chip processed RNA were hybridized with capture probes on the reaction chamber surface and identification was achieved by detection of fluorescence tags. The application of the mentioned techniques and materials proved to allow the development of low-cost, disposable albeit multi-functional microfluidic system, performing heating, temperature sensing and chemical reaction processes in the same device. By proving its effectiveness, this device contributes a reference to show the integration potential of fully thermoplastic devices in biosensor systems.

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Experimental Setting for Applying Mechanical Stimuli to Study the Endothelial Response of Ex Vivo Vessels under Realistic Pathophysiological Environments

Life ◽

10.3390/life11070671 ◽

2021 ◽

Vol 11 (7) ◽

pp. 671

Author(s):

Ana Osuna ◽

Anna Ulldemolins ◽

Hector Sanz-Fraile ◽

Jorge Otero ◽

Núria Farré ◽

...

Keyword(s):

Ex Vivo ◽

Low Cost ◽

Technical Information ◽

Rabbit Aorta ◽

Pressure Waveform ◽

Mechanical Stimuli ◽

Experimental Setting ◽

Endothelial Response ◽

Flow Through ◽

Open Source Hardware

This paper describes the design, construction and testing of an experimental setting, making it possible to study the endothelium under different pathophysiological conditions. This novel experimental approach allows the application of the following stimuli to an ex vivo vessel in a physiological bath: (a) a realistic intravascular pressure waveform defined by the user; (b) shear stress in the endothelial layer since, in addition to the pressure waveform, the flow through the vessel can be independently controlled by the user; (c) conditions of hypo/hyperoxia and hypo/hypercapnia in an intravascular circulating medium. These stimuli can be applied alone or in different combinations to study possible synergistic or antagonistic effects. The setting performance is illustrated by a proof of concept in an ex vivo rabbit aorta. The experimental setting is easy to build by using very low-cost materials widely available. Online Supplement files provide all the technical information (e.g., circuits, codes, 3D printer drivers) following an open-source hardware approach for free replication.

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A low-cost, portable system for the assessment of the postural response of wheelchair users to perturbations

IEEE Transactions on Rehabilitation Engineering ◽

10.1109/86.808947 ◽

1999 ◽

Vol 7 (4) ◽

pp. 435-442 ◽

Cited By ~ 4

Author(s):

D.G. Kamper ◽

T.C. Adams ◽

S.I. Reger ◽

M. Parnianpour ◽

K. Barin ◽

...

Keyword(s):

Low Cost ◽

Postural Response ◽

Wheelchair Users ◽

Portable System

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On-Chip Fabrication of None-Dead-Volume Microtips for ESI-MS Applications

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.121-123.611 ◽

2007 ◽

Vol 121-123 ◽

pp. 611-614

Author(s):

Che Hsin Lin ◽

Jen Taie Shiea ◽

Yen Lieng Lin

Keyword(s):

Surface Tension ◽

Low Cost ◽

Microfluidic Channel ◽

Dead Volume ◽

Esi Ms ◽

Rapid Fabrication ◽

Chip Fabrication ◽

Novel Method ◽

On Chip ◽

Highly Uniform

This paper proposes a novel method to on-chip fabricate a none-dead-volume microtip for ESI-MS applications. The microfluidic chip and ESI tip are fabricated in low-cost plastic based materials using a simple and rapid fabrication process. A constant-speed-pulling method is developed to fabricate the ESI tip by pulling mixed PMMA glue using a 30-μm stainless wire through the pre-formed microfluidic channel. The equilibrium of surface tension of PMMA glue will result in a sharp tip after curing. A highly uniform micro-tip can be formed directly at the outlet of the microfluidic channel with minimum dead-volume zone. Detection of caffeine, myoglobin, lysozyme and cytochrome C biosamples confirms the microchip device can be used for high resolution ESI-MS applications.

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Optical MEMS platform for low-cost on-chip integration of planar light circuits and optical switching

10.1117/12.528996 ◽

2004 ◽

Author(s):

Kristine A. German ◽

Joel Kubby ◽

Jingkuang Chen ◽

James Diehl ◽

Kathleen Feinberg ◽

...

Keyword(s):

Optical Switching ◽

Low Cost ◽

Optical Mems ◽

On Chip

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On-chip electrochemical detection of CdS quantum dots using normal and multiple recycling flow through modes

Lab on a Chip ◽

10.1039/c2lc00007e ◽

2012 ◽

Vol 12 (11) ◽

pp. 2000 ◽

Cited By ~ 23

Author(s):

Mariana Medina-Sánchez ◽

Sandrine Miserere ◽

Sergio Marín ◽

Gemma Aragay ◽

Arben Merkoçi

Keyword(s):

Quantum Dots ◽

Electrochemical Detection ◽

Cds Quantum Dots ◽

Flow Through ◽

On Chip ◽

Multiple Recycling

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Effects of season on ecological processes in extensive earthen tilapia ponds in Southeastern Brazil

Brazilian Journal of Biology ◽

10.1590/1519-6984.06414 ◽

2015 ◽

Vol 75 (4 suppl 1) ◽

pp. 97-107 ◽

Cited By ~ 1

Author(s):

E. G. P. Favaro ◽

L. H. Sipaúba-Tavares ◽

A. Milstein

Keyword(s):

Low Cost ◽

Stocking Density ◽

Grazing Pressure ◽

Southeastern Brazil ◽

Negative Effects ◽

Ecological Processes ◽

Pond Ecosystem ◽

Disposal Option ◽

Flow Through ◽

Dry Seasons

Abstract In Southeastern Brazil tilapia culture is conducted in extensive and semi-intensive flow-through earthen ponds, being water availability and flow management different in the rainy and dry seasons. In this region lettuce wastes are a potential cheap input for tilapia culture. This study examined the ecological processes developing during the rainy and dry seasons in three extensive flow-through earthen tilapia ponds fertilized with lettuce wastes. Water quality, plankton and sediment parameters were sampled monthly during a year. Factor analysis was used to identify the ecological processes occurring within the ponds and to construct a conceptual graphic model of the pond ecosystem functioning during the rainy and dry seasons. Processes related to nitrogen cycling presented differences between both seasons while processes related to phosphorus cycling did not. Ecological differences among ponds were due to effects of wind protection by surrounding vegetation, organic loading entering, tilapia density and its grazing pressure on zooplankton. Differences in tilapia growth among ponds were related to stocking density and ecological process affecting tilapia food availability and intraspecific competition. Lettuce wastes addition into the ponds did not produce negative effects, thus this practice may be considered a disposal option and a low-cost input source for tilapia, at least at the amounts applied in this study.

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