Abstract: This invention provides technology for transdifferentiating cells from one cell type to another. The cells are cultured with one or more vector-free gene regulator oligonucleotides concurrently or in succession, and then harvested when cell markers or the morphology of the culture shows that transdifferentiation is complete. Suitable gene regular oligonucleotides include microRNAs and messenger RNAs that encode a differentiation factor. Conditions for transdifferentiation can be optimized by dividing cells into different culture chambers of a microfluidic device. Cells are cultured with different additives in each chamber, and then compared. Transdifferentiated cells produced according to this invention can provide a consistent source of tissue for use in regenerative medicine.

Abstract: The invention provides an assay method for detection and/or quantification of a plurality of nucleic acid or protein targets in a sample. In the method probes are used to associate a detectable tag sequence with each of the selected targets present in the sample. Probes or primers sufficient to identify at least 25, and preferably at least 500, different targets are used. The method involves segregating aliquots of the sample from each other and detecting the tag sequences in each aliquot.

Abstract: Multilevel microfluidic devices include a control line that can simultaneously actuate valves for both sample and reagent lines. Microfluidic devices are configured to contain a first reagent in a first chamber and a second reagent in a second chamber, where either or both of the first and second reagents are contained at a desired or selected pressure. Operation of a microfluidic device includes transmitting second reagent from the second chamber to the first chamber, for mixing or contact with the first reagent. Microfluidic device features such as channels, valves, chambers, can be at least partially contained, embedded, or formed by or within one or more layers or levels of an elastomeric block.

Abstract: The present invention provides assay methods that increase the number of samples and/or target nucleic acids that can be analyzed in a single assay.

Abstract: The presence of a detectable entity within a detection volume of a microfabricated elastomeric structure is sensed through a change in the electrical or magnetic environment of the detection volume. In embodiments utilizing electronic detection, an electric field is applied to the detection volume and a change in impedance, current, or combined impedance and current due to the presence of the detectable entity is measured. In embodiments utilizing magnetic detection, the magnetic properties of a magnetized detected entity alter the magnetic field of the detection volume. This changed magnetic field induces a current which can reveal the detectable entity. The change in resistance of a magnetoresistive element may also reveal the passage of a magnetized detectable entity.

Abstract: Devices and methods for performing the relative concentration of a target in a sample, the sample containing both target and non-target components, the method performed by partitioning the sample into a large number of reaction volumes such that the target is concentrated relative to the non-target, and performing a detection assay upon each reaction volume to detect the target.

Abstract: The invention provides an assay method for detection and/or quantification of a plurality of nucleic acid or protein targets in a sample. In the method probes are used to associate a detectable tag sequence with each of the selected targets present in the sample. Probes or primers sufficient to identify at least 25, and preferably at least 500, different targets are used. The method involves segregating aliquots of the sample from each other and detecting the tag sequences in each aliquot.

Abstract: The present invention provides assay methods that increase the number of samples and/or target nucleic acids that can be analyzed in a single assay. In certain embodiments, an assay method entails separately subjecting S samples to an encoding reaction that produces a set of T tagged target nucleotide sequences, each tagged target nucleotide sequence including a sample-specific nucleotide tag and a target nucleotide sequence. In some embodiments, an assay method entails separately subjecting S samples to an encoding reaction that produces a set of T tagged target nucleotide sequences, each tagged target nucleotide sequence including a first nucleotide tag linked to a target nucleotide sequence, which is linked to a second nucleotide tag. In either case, the tagged target nucleotide sequences from the S samples can be mixed to form an assay mixture and subsequently assayed.

Abstract: Multilevel microfluidic devices include a control line that can simultaneously actuate valves for both sample and reagent lines. Microfluidic devices are configured to contain a first reagent in a first chamber and a second reagent in a second chamber, where either or both of the first and second reagents are contained at a desired or selected pressure. Operation of a microfluidic device includes transmitting second reagent from the second chamber to the first chamber, for mixing or contact with the first reagent. Microfluidic device features such as channels, valves, chambers, can be at least partially contained, embedded, or formed by or within one or more layers or levels of an elastomeric block.

Abstract: Multilevel microfluidic devices include a control line that can simultaneously actuate valves for both sample and reagent lines. Microfluidic devices are configured to contain a first reagent in a first chamber and a second reagent in a second chamber, where either or both of the first and second reagents are contained at a desired or selected pressure. Operation of a microfluidic device includes transmitting second reagent from the second chamber to the first chamber, for mixing or contact with the first reagent. Microfluidic device features such as channels, valves, chambers, can be at least partially contained, embedded, or formed by or within one or more layers or levels of an elastomeric block.

Abstract: The presence of a detectable entity within a detection volume of a microfabricated elastomeric structure is sensed through a change in the electrical or magnetic environment of the detection volume. In embodiments utilizing electronic detection, an electric field is applied to the detection volume and a change in impedance, current, or combined impedance and current due to the presence of the detectable entity is measured. In embodiments utilizing magnetic detection, the magnetic properties of a magnetized detected entity alter the magnetic field of the detection volume. This changed magnetic field induces a current which can reveal the detectable entity. The change in resistance of a magnetoresistive element may also reveal the passage of a magnetized detectable entity.

Abstract: The presence of a detectable entity within a detection volume of a microfabricated elastomeric structure is sensed through a change in the electrical or magnetic environment of the detection volume. In embodiments utilizing electronic detection, an electric field is applied to the detection volume and a change in impedance, current, or combined impedance and current due to the presence of the detectable entity is measured. In embodiments utilizing magnetic detection, the magnetic properties of a magnetized detected entity alter the magnetic field of the detection volume. This changed magnetic field induces a current which can reveal the detectable entity. The change in resistance of a magnetoresistive element may also reveal the passage of a magnetized detectable entity.

Abstract: An M×N matrix microfluidic device for performing a matrix of reactions, the device having a plurality of reaction cells in communication with one of either a sample inlet or a reagent inlet through a via formed within an elastomeric block of the device. Methods provided include a method for forming vias in parallel in an elastomeric layer of an elastomeric block of a microfluidic device, the method comprising using patterned photoresist masks and etching reagents to etch away regions or portions of an elastomeric layer of the elastomeric block.

Abstract: Multilevel microfluidic devices include a control line that can simultaneously actuate valves for both sample and reagent lines. Microfluidic devices are configured to contain a first reagent in a first chamber and a second reagent in a second chamber, where either or both of the first and second reagents are contained at a desired or selected pressure. Operation of a microfluidic device includes transmitting second reagent from the second chamber to the first chamber, for mixing or contact with the first reagent. Microfluidic device features such as channels, valves, chambers, can be at least partially contained, embedded, or formed by or within one or more layers or levels of an elastomeric block.

Abstract: The presence of a detectable entity within a detection volume of a microfabricated elastomeric structure is sensed through a change in the electrical or magnetic environment of the detection volume. In embodiments utilizing electronic detection, an electric field is applied to the detection volume and a change in impedance, current, or combined impedance and current due to the presence of the detectable entity is measured. In embodiments utilizing magnetic detection, the magnetic properties of a magnetized detected entity alter the magnetic field of the detection volume. This changed magnetic field induces a current which can reveal the detectable entity. The change in resistance of a magnetoresistive element may also reveal the passage of a magnetized detectable entity.

Abstract: A variety of elastomeric-based microfluidic devices and methods for using and manufacturing such devices are provided. Certain of the devices have arrays of reaction sites to facilitate high throughput analyses. Some devices also include reaction sites located at the end of blind channels at which reagents have been previously deposited during manufacture. The reagents become suspended once sample is introduced into the reaction site. The devices can be utilized with a variety of heating devices and thus can be used in a variety of analyses requiring temperature control, including thermocycling applications such as nucleic acid amplification reactions, genotyping and gene expression analyses.

Abstract: A variety of elastomeric-based microfluidic devices and methods for using and manufacturing such devices are provided. Certain of the devices have arrays of reaction sites to facilitate high throughput analyses. Some devices also include reaction sites located at the end of blind channels at which reagents have been previously deposited during manufacture. The reagents become suspended once sample is introduced into the reaction site. The devices can be utilized with a variety of heating devices and thus can be used in a variety of analyses requiring temperature control, including thermocycling applications such as nucleic acid amplification reactions, genotyping and gene expression analyses.

Abstract: An M×N matrix microfluidic device for performing a matrix of reactions, the device having a plurality of reaction cells in communication with one of either a sample inlet or a reagent inlet through a via formed within an elastomeric block of the device. Methods provided include a method for forming vias in parallel in an elastomeric layer of an elastomeric block of a microfluidic device, the method comprising using patterned photoresist masks and etching reagents to etch away regions or portions of an elastomeric layer of the elastomeric block.

Abstract: A variety of elastomeric-based microfluidic devices and methods for using and manufacturing such devices are provided. Certain of the devices have arrays of reaction sites to facilitate high throughput analyses. Some devices also include reaction sites located at the end of blind channels at which reagents have been previously deposited during manufacture. The reagents become suspended once sample is introduced into the reaction site. The devices can be utilized with a variety of heating devices and thus can be used in a variety of analyses requiring temperature control, including thermocycling applications such as nucleic acid amplification reactions, genotyping and gene expression analyses.

Abstract: A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.