Showing papers by "David E. Cliffel published in 2002"
Patent•
06 Aug 2002TL;DR: In this paper, an apparatus and methods for detecting at least one analyte of interest either produced or consumed by a plurality of cells is presented. But the method is not suitable for the detection of analyte-of-interest (AoI) objects.
Abstract: An apparatus and methods for detecting at least one analyte of interest either produced or consumed by a plurality of cell. In one embodiment of the present invention, the method includes the steps of providing a housing defining a chamber, placing a plurality of cells in the chamber, and simultaneously detecting at least two analytes of interest either produced or consumed by the plurality of cells in the chamber.
58 citations
Patent•
06 Aug 2002TL;DR: In this article, an apparatus and methods for monitoring the status of a cell that consumes oxygen is presented. But the method is not suitable for the monitoring of a single cell, and it is difficult to implement in practice.
Abstract: An apparatus and methods for monitoring the status of a cell that consumes oxygen. In one embodiment of the present invention, the method includes the steps of confining the cell in a sensing volume, measuring dynamically intracellular or extracellular signaling of the cell, and determining the status of the cell from the measured intracellular or extracellular signaling of the cell.
29 citations
Patent•
06 Aug 2002TL;DR: In this article, an apparatus and methods for using biological material to discriminate an agent is presented. But the method is not suitable for the detection of malicious agents. And the method does not include the step of quantifying the agent from the measured response.
Abstract: An apparatus and methods for using biological material to discriminate an agent. In one embodiment of the present invention, the method includes the steps of providing at least one cell, exposing at least one cell to an agent, measuring the response of the cell to the agent in terms of a physical quantity related to at least one of the cellular physiological activities of the cell, and identifying the agent from the measured response. The method further includes the step of quantifying the agent from the measured response.
14 citations
23 Oct 2002
TL;DR: Initial results from measurements of oxygen uptake and/or acidification rates of single cardiac myocytes in subnanoliter volumes with simultaneous recording of the transmembrane potential using fluorescent dyes are presented.
Abstract: To monitor the dynamics of single cells with a high bandwidth, we have developed a BioMEMS device wherein a single cell can be trapped and monitored in a subnanoliter volume that provides control over the extracellular environment. The PDMS multilayer chips, based on a technology pioneered by Stephen Quake, et al., have fluidic and control layers separated by a thin membrane. Intersections of fluidic and control layers serve as valves that can be actuated by pressurizing control lines. A series array of valves can be used as a peristaltic pump. The polymer structure is sealed to an interdigitated thin-film microelectrode array on a glass slide for electrochemical detection of various analytes and simultaneous fluorescence imaging. On-chip pumps and valves allow the transport of fluid to the sampling volume and its isolation and flushing. The BioMEMS device can be used as a biosensor by incorporating living cells into the sampling volume. We present initial results from measurements of oxygen uptake and/or acidification rates of single cardiac myocytes in subnanoliter volumes with simultaneous recording of the transmembrane potential using fluorescent dyes. The technology can be easily extended for high-content drug screening devices or for measuring cellular response and dynamics with millisecond resolution.
1 citations
01 Mar 2002
TL;DR: In this article, a BioMEMS device was developed to monitor the dynamics of single cells with a high bandwidth, where a single cell can be trapped and monitored in a subnanoliter volume that provides control over the extracellular environment.
Abstract: To monitor the dynamics of single cells with a high bandwidth, we have developed a BioMEMS device wherein a single cell can be trapped and monitored in a subnanoliter volume that provides control over the extracellular environment. The PDMS multilayer chips, based on a technology pioneered by Stephen Quake, et al., have fluidic and control layers separated by a thin membrane. Intersections of fluidic and control layers serve as valves that can be actuated by pressurizing control lines. A series array of valves can be used as a peristaltic pump. The polymer structure is sealed to an interdigitated thin-film microelectrode array on a glass slide for electrochemical detection of various analytes and simultaneous fluorescence imaging. On-chip pumps and valves allow the transport of fluid to the sampling volume and its isolation and flushing. The BioMEMS device can be used as a biosensor by incorporating living cells into the sampling volume. We present initial results from measurements of oxygen uptake and/or acidification rates of single cardiac myocytes in subnanoliter volumes with simultaneous recording of the transmembrane potential using fluorescent dyes. The technology can be easily extended for high-content drug screening devices or for measuring cellular response and dynamics with millisecond resolution.
Patent•
06 Aug 2002
TL;DR: In this paper, the authors propose a method for confining a cellule dans un volume de detection, mesurer de maniere dynamique la transmission des signaux intracellulaires and extracellulaire de the cellule, and determiner l'etat de la cellule a partir de the transmission mesuree de ses signaux.
Abstract: L'invention porte sur un appareil et sur des procedes de surveillance de l'etat d'une cellule qui consomme de l'oxygene. Selon un mode de mise en oeuvre de l'invention, le procede consiste a confiner la cellule dans un volume de detection, mesurer de maniere dynamique la transmission des signaux intracellulaires et extracellulaires de la cellule et determiner l'etat de la cellule a partir de la transmission mesuree de ses signaux.