Read by QxMD icon Read

Lab on a Chip

D Caballero, J Katuri, J Samitier, S Sánchez
The ubiquitous random motion of mesoscopic active particles, such as cells, can be "rectified" or directed by embedding the particles in systems containing local and periodic asymmetric cues. Incorporated on lab-on-a-chip devices, these microratchet-like structures can be used to self-propel fluids, transport particles, and direct cell motion in the absence of external power sources. In this Focus article we discuss recent advances in the use of ratchet-like geometries in microfluidics which could open new avenues in biomedicine for applications in diagnosis, cancer biology, and bioengineering...
October 19, 2016: Lab on a Chip
Yonglei Li, Yangfu Fang, Jiao Wang, Lu Wang, Shiwei Tang, Chunping Jiang, Lirong Zheng, Yongfeng Mei
Miniaturization of functional devices and systems demands new design and fabrication approaches for lab-on-a-chip application and optical integrative systems. By using a direct laser writing (DLW) technique based on two-photon polymerization (TPP), a highly integrative optofluidic refractometer is fabricated and demonstrated based on tubular optical microcavities coupled with waveguides. Such tubular devices can support high quality factor (Q-factor) up to 3600 via fiber taper coupling. Microtubes with various diameters and wall thicknesses are constructed with optimized writing direction and conditions...
October 18, 2016: Lab on a Chip
R Peng, Z Sonner, A Hauke, E Wilder, J Kasting, T Gaillard, D Swaille, F Sherman, X Mao, J Hagen, R Murdock, J Heikenfeld
Wearable sweat biosensensing technology has dominantly relied on techniques which place planar-sensors or fluid-capture materials directly onto the skin surface. This 'on-skin' approach can result in sample volumes in the μL regime, due to the roughness of skin and/or due to the presence of hair. Not only does this increase the required sampling time to 10's of minutes or more, but it also increases the time that sweat spends on skin and therefore increases the amount of analyte contamination coming from the skin surface...
October 18, 2016: Lab on a Chip
Lu Mi, Liang Huang, Junxiang Li, Guoqiang Xu, Qiong Wu, Wenhui Wang
Single cell traps have important applications in biological cell manipulation and analysis. This paper describes a novel single cell trap design and device with a matrix of cell trap units inspired by an equivalent resistive electric circuit. This fluidic device follows the least flow resistance path principle of such devices allowing deterministic single cell trapping with high efficiency and flexibility for large scale cell patterning.
October 17, 2016: Lab on a Chip
Matthew Y H Tang, Ho Cheung Shum
We present a wash-free high-sensitivity immunoassay of C-reactive proteins with droplet microfluidics. Microbeads are encapsulated within droplets for the immunoassay, and the droplets are scanned by a fluorescence detection platform to quantify the amount of proteins captured on the microbeads. The limit of detection determined by our platform is 0.01 μg mL(-1), which is ten times more sensitive than conventional high-sensitivity C-reactive protein assays. With the decrease in diffusion distance within droplets, the immunoassay requires only half of the time required for similar conventional approaches...
October 14, 2016: Lab on a Chip
Chung-Hsuan Wu, Wei-Han Wang, Chien-Chong Hong, Kuo Chu Hwang
This paper presents a novel disposable breath-sensing tube with an on-tube single-nanowire (NW) sensor array for noninvasive, simple, and on-site detection of exhaled breath biomarkers. Although various noninvasive detection methods for lung cancer biomarkers in breath samples exist, they are unsuitable for self-diagnostics and immediate detection because they entail complicated handling procedures and are time intensive. In this study, we simulated, fabricated, and characterized disposable nanosensors by using single TiO2 and Ag NWs in flexible plastic tubes...
October 14, 2016: Lab on a Chip
A Nakajima, M Ishida, T Fujimori, Y Wakamoto, S Sawai
Studies of chemotactic cell migration rely heavily on various assay systems designed to evaluate the ability of cells to move in response to attractant molecules. In particular, the development of microfluidics-based devices in recent years has made it possible to spatially distribute attractant molecules in graded profiles that are sufficiently stable and precise to test theoretical predictions regarding the accuracy and efficiency of chemotaxis and the underlying mechanism of stimulus perception. However, because the gradient is fixed in a direction orthogonal to the laminar flow and thus the chamber geometry, conventional devices are limited for the study of cell re-orientation to gradients that move or change directions...
October 13, 2016: Lab on a Chip
Li Dong, Matteo Cornaglia, Thomas Lehnert, Martin A M Gijs
Like other animals, C. elegans nematodes have the ability to socially interact and to communicate through exchange and sensing of small soluble signaling compounds that help them cope with complex environmental conditions. For the time being, worm biocommunication assays are being performed mainly on agar plates; however, microfluidic assays may provide significant advantages compared to traditional methods, such as control of signaling molecule concentrations and gradients or confinement of distinct worm populations in different microcompartments...
October 13, 2016: Lab on a Chip
Rahim Rahimi, Su Su Htwe, Manuel Ochoa, Amy Donaldson, Michael Zieger, Rajiv Sood, Ali Tamayol, Ali Khademhosseini, Amir M Ghaemmaghami, Babak Ziaie
Culturing cells at the air-liquid interface (ALI) is essential for creating functional in vitro models of lung tissues. We present the use of direct-patterned laser-treated hydrophobic paper as an effective semi-permeable membrane, ideal for ALI cell culture. The surface properties of the paper are modified through a selective CO2 laser-assisted treatment to create a unique porous substrate with hydrophilic regions that regulate fluid diffusion and cell attachment. To select the appropriate model, four promising hydrophobic films were compared with each other in terms of gas permeability and long-term strength in an aqueous environment (wet-strength)...
October 12, 2016: Lab on a Chip
Ophélie I Berthuy, Sinan K Muldur, François Rossi, Pascal Colpo, Loïc J Blum, Christophe A Marquette
Microarray technology was developed in the early 1990s to measure the transcription levels of thousands of genes in parallel. The basic premise of high-density arraying has since been expanded to create cell microarrays. Cells on chip are powerful experimental tools for high-throughput and multiplex screening of samples or cellular functions. Miniaturization increases assay throughput while reducing both reagent consumption and cell population heterogeneity effect, making these systems attractive for a wide range of assays, from drug discovery to toxicology, stem cell research and therapy...
October 12, 2016: Lab on a Chip
Aghiad Ghazal, Josiane P Lafleur, Kell Mortensen, Jörg P Kutter, Lise Arleth, Grethe V Jensen
The increasingly narrow and brilliant beams at X-ray facilities reduce the requirements for both sample volume and data acquisition time. This creates new possibilities for the types and number of sample conditions that can be examined but simultaneously increases the demands in terms of sample preparation. Microfluidic-based sample preparation techniques have emerged as elegant alternatives that can be integrated directly into the experimental X-ray setup remedying several shortcomings of more traditional methods...
October 12, 2016: Lab on a Chip
M-C Horny, M Lazerges, J-M Siaugue, A Pallandre, D Rose, F Bedioui, C Deslouis, A-M Haghiri-Gosnet, J Gamby
Here, we describe the transposition of an ultramicroelectrode (UME) setup into a microfluidic chip configuration for DNA biosensors. The hydrodynamic properties of the fluidic channel microelectrode were screened with an [Fe(iii)(CN)6](3-)/[Fe(ii)(CN)6](4-) redox couple by cyclic voltammetry to provide a basis for further biological processes. A 23-base DNA probe was self-assembled into a monolayer on gold microelectrodes both in classical configuration and integrated in a microfluidic setup. Special interest was focused on the DNA target mimicking the liver-specific micro-ribonucleic acid 122 (miRNA122)...
October 10, 2016: Lab on a Chip
Gihoon Choi, Daniel Song, Sony Shrestha, Jun Miao, Liwang Cui, Weihua Guan
In response to the urgent need of a field-deployable and highly sensitive malaria diagnosis, we developed a standalone, "sample-in-answer-out" molecular diagnostic system (AnyMDx) to enable quantitative molecular analysis of blood-borne malaria in low resource areas. The system consists of a durable battery-powered analyzer and a disposable microfluidic compact disc loaded with reagents ready for use. A low power thermal module and a novel fluorescence-sensing module are integrated into the analyzer for real-time monitoring of loop-mediated isothermal nucleic acid amplification (LAMP) of target parasite DNA...
October 10, 2016: Lab on a Chip
Javier L Prieto, Hao-Wei Su, Han Wei Hou, Miguel Pinilla Vera, Bruce D Levy, Rebecca M Baron, Jongyoon Han, Joel Voldman
Sepsis is a potentially lethal condition that may be ameliorated through early monitoring of circulating activated leukocytes for faster stratification of severity of illness and improved administration of targeted treatment. Characterization of the intrinsic electrical properties of leukocytes is label-free and can provide a quick way to quantify the number of activated cells as sepsis progresses. Iso-dielectric separation (IDS) uses dielectrophoresis (DEP) to characterize the electrical signatures of cells...
October 7, 2016: Lab on a Chip
Nan-Nan Deng, Wei Wang, Xiao-Jie Ju, Rui Xie, Liang-Yin Chu
The precise manipulation of droplets in microfluidics has revolutionized a myriad of drop-based technologies, such as multiple emulsion preparation, drop fusion, drop fission, drop trapping and drop sorting, which offer promising new opportunities in chemical and biological fields. In this paper, we present an interfacial-tension-directed strategy for the migration of droplets across liquid-liquid laminar streams. By carefully controlling the interfacial energies, droplets of phase A are able to pass across the laminar interfaces of two immiscible fluids from phase B to phase C due to a positive spreading coefficient of phase C over phase B...
October 5, 2016: Lab on a Chip
Yankan Jia, Yukun Ren, Weiyu Liu, Likai Hou, Ye Tao, Qingming Hu, Hongyuan Jiang
We utilize an ac electric field to trigger the on-demand fusion of two aqueous cores inside water-in-oil-in-water (W/O/W) double-emulsion drops. We attribute the coalescence phenomenon to field-induced structural polarization and breakdown of the stress balance at interfaces. This method provides not only accurate control over the reaction time of coalescence but also protection of the reaction from cross contamination.
October 4, 2016: Lab on a Chip
Alborz Feizi, Yibo Zhang, Alon Greenbaum, Alex Guziak, Michelle Luong, Raymond Yan Lok Chan, Brandon Berg, Haydar Ozkan, Wei Luo, Michael Wu, Yichen Wu, Aydogan Ozcan
Monitoring yeast cell viability and concentration is important in brewing, baking and biofuel production. However, existing methods of measuring viability and concentration are relatively bulky, tedious and expensive. Here we demonstrate a compact and cost-effective automatic yeast analysis platform (AYAP), which can rapidly measure cell concentration and viability. AYAP is based on digital in-line holography and on-chip microscopy and rapidly images a large field-of-view of 22.5 mm(2). This lens-free microscope weighs 70 g and utilizes a partially-coherent illumination source and an opto-electronic image sensor chip...
September 30, 2016: Lab on a Chip
(no author information available yet)
No abstract text is available yet for this article.
October 21, 2016: Lab on a Chip
(no author information available yet)
No abstract text is available yet for this article.
October 21, 2016: Lab on a Chip
(no author information available yet)
No abstract text is available yet for this article.
October 21, 2016: Lab on a Chip
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"