Abstract: A method of sequencing a polynucleotide strand can include providing the polynucleotide strand with a primer annealed thereto and a polymerase operably bound to the polynucleotide strand; successively exposing the polynucleotide strand to the flow of four different dNTPs according to a first predetermined ordering; and successively exposing the polynucleotide strand to the flow of four different dNTPs according to a second predetermined ordering, wherein the second predetermined ordering is different from the first predetermined ordering.

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 system and machine readable medium for nucleic acid sequencing includes disposing template polynucleotide strands in defined spaces disposed on a sensor array, at least some of the template polynucleotide strands having a sequencing primer and a polymerase operably bound therewith; exposing the template polynucleotide strands to a series of flows of nucleotide species flowed according to a predetermined ordering; and determining, for each of the series of flows of nucleotide species, how many nucleotide incorporations occurred for that particular flow to determine a predicted sequence of nucleotides corresponding to the template polynucleotide strands, wherein the predetermined ordering (a) is not a series of consecutive repetitions of a 4-flow permutation of four different nucleotide species, (b) is not specifically tailored to a particular combination of a particular template polynucleotide strand to be sequenced and a particular sequencing primer to be used, and (c) comprises a phase-protecting flow orde

Abstract: Mathematical models for the analysis of signal data generated by sequencing of a polynucleotide strand using a pH-based method of detecting nucleotide incorporation(s). In an embodiment, the measured output signal from the reaction confinement region of a reactor array is mathematically modeled. The output signal may be modeled as a linear combination of one or more signal components, including a background signal component. This model is solved to determine the nucleotide incorporation signal. In another embodiment, the incorporation signal from the reaction confinement region of a reactor array is mathematically modeled.

Abstract: In one implementation, a method is described. The method includes determining an operational characteristic of sensors of a sensor array. The method further includes selecting a group of sensors in the array based on the operational characteristic of sensors in the group. The method further includes enabling readout of the sensors in the selected group. The method further includes receiving output signals from the enabled sensors, the output signals indicating chemical reactions occurring proximate to the sensors of the sensor array.

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: 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: 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: An apparatus comprising a chemical field effect transistor array in a circuit-supporting substrate is disclosed. The transistor array has disposed on its surface an array of sample-retaining regions capable of retaining a chemical or biological sample from a sample fluid. The transistor array has a pitch of 10 ?m or less and a sample-retaining region is positioned on at least one chemical field effect transistor which is configured to generate at least one output signal related to a characteristic of a chemical or biological sample in such sample-retaining region.

Abstract: Mathematical models for the analysis of signal data generated by sequencing of a polynucleotide strand using a pH-based method of detecting nucleotide incorporation(s). In an embodiment, the measured output signal from the reaction confinement region of a reactor array is mathematically modeled. The output signal may be modeled as a linear combination of one or more signal components, including a background signal component. This model is solved to determine the nucleotide incorporation signal. In another embodiment, the incorporation signal from the reaction confinement region of a reactor array is mathematically modeled.

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 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: In one implementation, a method is described. The method includes determining an operational characteristic of sensors of a sensor array. The method further includes selecting a group of sensors in the array based on the operational characteristic of sensors in the group. The method further includes enabling readout of the sensors in the selected group. The method further includes receiving output signals from the enabled sensors, the output signals indicating chemical reactions occurring proximate to the sensors of the sensor array.

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: An apparatus comprising a chemical field effect transistor array in a circuit-supporting substrate is disclosed. The transistor array has disposed on its surface an array of sample-retaining regions capable of retaining a chemical or biological sample from a sample fluid. The transistor array has a pitch of 10 ?m or less and a sample-retaining region is positioned on at least one chemical field effect transistor which is configured to generate at least one output signal related to a characteristic of a chemical or biological sample in such sample-retaining region.

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: 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 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.