Abstract:
Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in the concentration of inorganic pyrophosphate (PPi), hydrogen ions, and nucleotide triphosphates.
Abstract:
An automated template bead preparation system is provided and includes a membrane-based emulsion generation subsystems, a thermal plate and subsystem, and a continuous centrifugation emulsion breaking and templated bead collection subsystem. The emulsion generation subsystem provides uniformity in the preparation of an inverse emulsion and may be used to create large or small volume inverse emulsions rapidly and reproducibly. An emulsion-generating device is provided that can supply a continuous stream of an inverse emulsion to a thermal subsystem, in automated fashion. The thermal subsystem can treat an inverse emulsion passed therethrough. The continuous centrifugation subsystem can continuously break a thermally cycled inverse emulsion and collect template beads formed in the aqueous microreactor droplets of the inverse emulsion.
Abstract:
A buffered suspension includes a surfactant and a solid buffer particulate having a point of zero charge at least 1.2 pH units different that the pH of the buffered suspension. The buffered suspension can be prepared by mixing a stock solution with the solid buffer particulate and titrating. A method of preforming a pH sensitive process includes drawing the buffered suspension from a reservoir, filtering the solid buffer particulate from the buffered suspension, and applying the filtered solution to a sensor.
Abstract:
A method of preparing reagents includes inserting a cartridge into an instrument. The cartridge includes a plurality of reagent enclosures disposed in a cavity of the cartridge and exposing a port to an exterior of the cartridge. Each reagent enclosure includes a reagent container including a reagent and an internal cavity defining a compressible volume, an opening defined through the reagent container to the internal cavity. The method further includes connecting a plurality of fluid ports to the openings of the plurality of reagent enclosures; applying a solution through the fluid ports to at least partially fill the plurality of reagent enclosures; and cycling a pressure of the cavity, whereby for each of the reagent enclosures, during increasing pressure, the solution enters the internal cavity of the reagent container, combines with the reagent, and compresses the compressible volume, and during decreasing pressure, the compressible volume decreases and the reagent is ejected through the opening.
Abstract:
An apparatus for preparing a reagent solution includes an enclosure and a container disposed within the enclosure. The container defines an internal cavity having a compressible volume and defines a passage providing fluidic communication between the internal cavity and the exterior of the container. Optionally, a compressible member is disposed within the internal cavity. A reagent is disposed within the internal cavity.
Abstract:
A valve for regulating fluid flow includes a housing base defining a lower cavity and comprising a pinch structure within the lower cavity, a gas inlet providing external access to the lower cavity, a base fluid inlet, and a base fluid outlet. A housing cover defines an upper cavity and comprises a cover fluid inlet and a cover fluid outlet. The cover fluid inlet is in fluidic communication with the base fluid outlet between the upper cavity and the lower cavity, and the cover fluid outlet provides external access from the upper cavity. A diaphragm is disposed between the housing base and the housing cover. A pinch plate is disposed in the lower cavity and comprises a pinch point disposed opposite the pinch structure. A pinch tube is in fluidic communication between the base fluid inlet and the base fluid outlet in the lower cavity.
Abstract:
The invention provides a passive fluidics circuit for directing different fluids to a common volume, such as a reaction chamber or flow cell, without intermixing or cross contamination. The direction and rate of flow through junctions, nodes and passages of the fluidics circuit are controlled by the states of upstream valves (e.g. opened or closed), differential fluid pressures at circuit inlets or upstream reservoirs, flow path resistances, and the like. Free diffusion or leakage of fluids from unselected inlets into the common outlet or other inlets at junctions or nodes is prevented by the flow of the selected inlet fluid, a portion of which sweeps by the inlets of unselected fluids and exits the fluidics circuit by waste ports, thereby creating a barrier against undesired intermixing with the outlet flow through leakage or diffusion. The invention is particularly advantageous in apparatus for performing sensitive multistep reactions, such as pH-based DNA sequencing reactions.
Abstract:
A valve for regulating fluid flow includes a housing base defining a lower cavity and comprising a pinch structure within the lower cavity, a gas inlet providing external access to the lower cavity, a base fluid inlet, and a base fluid outlet. A housing cover defines an upper cavity and comprises a cover fluid inlet and a cover fluid outlet. The cover fluid inlet is in fluidic communication with the base fluid outlet between the upper cavity and the lower cavity, and the cover fluid outlet provides external access from the upper cavity. A diaphragm is disposed between the housing base and the housing cover. A pinch plate is disposed in the lower cavity and comprises a pinch point disposed opposite the pinch structure. A pinch tube is in fluidic communication between the base fluid inlet and the base fluid outlet in the lower cavity.
Abstract:
An automated template bead preparation system is provided and includes a membrane-based emulsion generation subsystems, a thermal plate and subsystem, and a continuous centrifugation emulsion breaking and templated bead collection subsystem. The emulsion generation subsystem provides uniformity in the preparation of an inverse emulsion and may be used to create large or small volume inverse emulsions rapidly and reproducibly. An emulsion-generating device is provided that can supply a continuous stream of an inverse emulsion to a thermal subsystem, in automated fashion. The thermal subsystem can treat an inverse emulsion passed therethrough. The continuous centrifugation subsystem can continuously break a thermally cycled inverse emulsion and collect template beads formed in the aqueous microreactor droplets of the inverse emulsion.
Abstract:
A method for sequencing a polynucleotide strand by using sequencing-by-synthesis techniques. To address the problem of incomplete extension (IE) and/or carry forward (CF) errors that can occur in sequencing-by-synthesis reactions, an alternative flow ordering of dNTPs is used. In contrast to conventional flow orderings, the dNTPs are flowed in an ordering that is not a continuous repeat of an ordering of the four different dNTPs. This alternate flow ordering may reduce the loss of phasic synchrony in the population of template polynucleotide strands that result from IE and/or CF errors.