3698results about "Stress based microorganism growth stimulation" patented technology

A method for delivering a therapeutic agent to a predetermined location in a host is disclosed, wherein a liposome-encapsulated therapeutic agent is administered to the host, and an electrical field which encompasses a predetermined region within the host is established, such that as the liposome-encapsulated agent is exposed to the electrical field the release of the agent from the liposome to the predetermined region is enhanced.

The present invention relates to an apparatus for conducting a variety of assays for the determination of analytes in liquid samples, and relates to the methods for such assays. In particular, the invention relates to a single-use cartridge designed to be adaptable to a variety of real-time assay protocols, preferably assays for the determination of analytes in biological samples using immunosensors or other ligand/ligand receptor-based biosensor embodiments. The cartridge provides novel features for processing a metered portion of a sample, for precise and flexible control of the movement of a sample or second fluid within the cartridge, for the amending of solutions with additional compounds during an assay, and for the construction of immunosensors capable of adaptation to diverse analyte measurements. The disclosed device and methods of use enjoy substantial benefits over the prior art, including simplicity of use by an operator, rapid in situ determinations of one or more analytes, and single-use methodology that minimizes the risk of contamination of both operator and patient. The disclosed invention is adaptable to the point-of-care clinical diagnostic field, including use in accident sites, emergency rooms, surgery, nursing homes, intensive care units, and non-medical environments.

An electrical current is created across an electrically conductive medium comprising a cell which may be part of a tissue of a living organism. A first electrical parameter which may be current, voltage, or electrical impedance is measured. A second electrical parameter which may be current, voltage or a combination of both is then adjusted and/or analyzed. Adjustments are carried out to facilitate analysis and/or obtain a desired degree of electroporation. Analysis is carried out to determine characteristics of the cell membrane and/or tissue.

The invention relates to a method for detecting analytes and to a device for carrying out the method, for use for analysis or diagnosis in the fields of chemistry, biochemistry, molecular genetics, food chemistry, biotechnology, the environment and medicine. Marker particles (5) with different electrical properties or a different relative permeability to those of the measuring solution (3) surrounding them are used to detect the analytes (8). The marker particles (5) either bond specifically to the analytes (8) or to a base (2) in competition with the analyte. The analytes (8) are detected by the changes in an electrical field or an electrical current generated by electrodes (2) or in an electrical voltage applied to an electrode or in a magnetic field, said changes being caused by marker particles which have bonded with the analytes or by marker particles which have instead bonded to the base in an electrical field.

A method of generating and recovering gas from naturally existing subsurface formations Of coal, carbonaceous shale or organic-rich shales comprising the steps Of: injecting into fracture of the subsurface formation, under substantially anaerobic conditions, a consortia of selected anaerobic, biological microorganisms for in situ conversion of organic compounds in said formation into methane and other compounds; and producing methane through at least one well extending from said subsurface formation to the surfaces.

An electrochemical device for moving particles covered with a protein is provided. The device includes at least two electrodes that are in contact with a liquid containing the protein-covered particles and a circuit that generates a potential difference in a range that does not cause electrolysis of the liquid between the electrodes. The particles are moved by electrophoresis in the direction of the arrangement of the electrodes. The invention provided herein has numerous applications, including use in a microorganism concentration condensing device, a blood component induction device, and/or a blood component induction method, and/or an electric appliance that decreases the concentration of microorganisms present on the surface of a heat exchanger.

The present invention relates to a microfluidic system for processing a cell-containing liquid. The system includes a lysing zone to receive the cell-containing sample and a positioning element to position the cell-containing sample in a lysing position in the vicinity of a lysing mechanism. The lysing mechanism releases intracellular material, such as DNA or RNA, from the cells. In one embodiment, the lysing mechanism includes electrodes for generating an electric field sufficient to release intracellular contents from the cells. Alternatively, the lysing mechanism may lyse the cells using chemical, heat and/or ultrasonic techniques or any combination of these techniques.

The present invention relates to a microfluidic system for processing a cell-containing liquid. The system includes a microfabricated substrate having an enrichment channel to prepare an enriched cell sample from the cell-containing liquid. A flow through member is in liquid communication with the enrichment zone. The flow through member substantially prevents cells of the cell-containing fluid from exiting the enrichment zone while allowing liquid of the cell-containing liquid to exit the enrichment zone. A gas actuator associated with the enrichment zone provides a gas pressure sufficient to move the enriched cell sample from the enrichment zone.

There is provided the reagent layer composition that can substantially reduce the measurement bias arising from hematocrits. The addition of fatty acid (4-20 carbons) and quaternary ammonium salt to a commonly used reagent layer composition composed of an enzyme, an electron transfer mediator, and several water soluble polymers not only reduce the hematocrit level-dependent bias but also provide very stable performance for an extended period of time. Disclosed are also various types of sub microliter sample volume electrochemical biosensors that are suitable to use with the reagent layer composition of present invention.

Apparatus and methods are provided for analysis of individual particles in a microfluidic device. The methods involve the immobilization of an array of particles in suspension and the application of experimental compounds. Such methods can also include electrophysiology studies including patch clamp recording, electroporation, or both in the same microfluidic device. The apparatus provided includes a microfluidic device coupled to a multi-well structure and an interface for controlling the flow of media within the microchannel device.

Methods for determining the presence of double stranded nucleic acids in a sample are provided. In the subject methods, nucleic acids present in a fluid sample are translocated through a nanopore, e.g. by application of an electric field to the fluid sample. The current amplitude through the nanopore is monitored during the translocation process and changes in the amplitude are related to the passage of single- or double-stranded molecules through the nanopore. The subject methods find use in a variety of applications in which the detection of the presence of double-stranded nucleic acids in a sample is desired, e.g. in hybridization assays, such as Northern blot assays, Southern blot assays, array based hybridization assays, etc.

Electroporation is performed in a controlled manner in either individual or multiple biological cells or biological tissue by monitoring the electrical impedance, defined herein as the ratio of current to voltage in the electroporation cell. The impedance detects the onset of electroporation in the biological cell(s), and this information is used to control the intensity and duration of the voltage to assure that electroporation has occurred without destroying the cell(s). This is applicable to electroporation in general. In addition, a particular method and apparatus are disclosed in which electroporation and/or mass transfer across a cell membrane are accomplished by securing a cell across an opening in a barrier between two chambers such that the cell closes the opening. The barrier is either electrically insulating, impermeable to the solute, or both, depending on whether pore formation, diffusive transport of the solute across the membrane, or both are sought. Electroporation is achieved by applying a voltage between the two chambers, and diffusive transport is achieved either by a difference in solute concentration between the liquids surrounding the cell and the cell interior or by a differential in concentration between the two chambers themselves. Electric current and diffusive transport are restricted to a flow path that passes through the opening.

The present invention is directed to devices and methods that apply ultrasonic energy for the purpose of inducing transfection and cell transformation. A sonoporation system in accordance with embodiments of the present invention includes an ultrasonic electrical energy generator connected to an ultrasonic transducer producing stress waves. The ultrasonic transducer is connected to a fluid containment tank configured to accept at least a portion of the ultrasonic transducer whereby the ultrasonic stress waves may be delivered into the fluid medium. A cell holder is configured to hold one or more cells desirable for transfection. A hydrophone may be electrically connected to an acoustic stress wave intensity detection circuit. A motion control system having an arm configured to receive one or both of the cell holder and the hydrophone is configured to provide motion of one or both of the cell holder and the hydrophone within the fluid medium.

An electrospraying apparatus and/or method is used to coat particles. For example, a flow including at least one liquid suspension may be provided through at least one opening at a spray dispenser end. The flow includes at least particles and a coating material. A spray of microdroplets suspending at least the particles is established forward of the spray dispenser end by creating a nonuniform electrical field between the spray dispenser end and an electrode electrically isolated therefrom. The particles are coated with at least a portion of the coating material as the microdroplet evaporates. For example, the suspension may include biological material particles.

An object of the invention is to provide a method for delivery of macromolecules into biological cells, such as Langerhans cells (22) in the epidermis (20) of a patient, which includes the steps of coating electodes (16) in an electrode assembly (12) with solid phase macromolecules to be delivered, such as a DNA, and/or RNA vaccine or a protein-based vaccine, attaching the electrode assembly (12) having the coated electrodes (16) to an electrode assembly holder (13), providing a waveform generator (15), establishing electrically conductive pathways between the electrodes (16), and the waveform generator (15), locating the electrodes (16) such that the biological cells are situated therebetween, such as by penetrating the needle electrode (16) into the epidermis (20) above the epidermal basal lamina, and providing pulse waveform from the waveform generator (15) to the electrodes (16), such that macromolecule on the electrodes (16) is driven off of the electrodes (16), and delivered into the biological cells, such as the Langerhans cells (22).

Disclosed is a chamber apparatus for electroporating in vitro relatively large volumes of a fluid medium carrying biological-cells-or-vesicles wherein-a reservoir for carrying said cells and vesicles is variable in its volume on demand and wherein the volume chosen is directly related to the volume of the sample to be electroporated. The apparatus has further embodiments wherein the chamber is disposable and can be operated either in isolation from a patient or connected thereto.