Described herein is an immobilization-free, electrochemical method of detecting a target DNA sequence in a sample. The method includes: incubating the sample with a detection mixture, applying an electric field including an alternating current electric field and a direct current offset to the detection mixture to concentrate nucleic acids in the sample and the nucleic acid probe on a positively charged working electrode, wherein a Class 2 Cas protein trans-cleaved electroactive probe is released from the nucleic acid probe when the target DNA is present in the sample and diffuses toward a negatively charged electrode; and measuring the current as potential is applied, wherein detection of a current in the detection mixture indicates the presence of the target DNA sequence in the sample.

Described herein is an immobilization-free, electrochemical method of detecting a target DNA sequence in a sample. The method includes: incubating the sample with a detection mixture, applying an electric field including an alternating current electric field and a direct current offset to the detection mixture to concentrate nucleic acids in the sample and the nucleic acid probe on a positively charged working electrode, wherein a Class 2 Cas protein trans-cleaved electroactive probe is released from the nucleic acid probe when the target DNA is present in the sample and diffuses toward a negatively charged electrode; and measuring the current as potential is applied, wherein detection of a current in the detection mixture indicates the presence of the target DNA sequence in the sample.

Described herein is an immobilization-free, electrochemical method of detecting a target DNA sequence in a sample. The method includes: incubating the sample with a detection mixture, applying an electric field including an alternating current electric field and a direct current offset to the detection mixture to concentrate nucleic acids in the sample and the nucleic acid probe on a positively charged working electrode, wherein a Class 2 Cas protein trans-cleaved electroactive probe is released from the nucleic acid probe when the target DNA is present in the sample and diffuses toward a negatively charged electrode; and measuring the current as potential is applied, wherein detection of a current in the detection mixture indicates the presence of the target DNA sequence in the sample.

Provided are methods for biological sample processing and analysis. A method can comprise providing a substrate configured to rotate. The substrate can comprise an array having immobilized thereto a biological analyte. A solution comprising a plurality of probes may be directed, via centrifugal force, across the substrate during rotation of the substrate, to couple at least one of the plurality of probes with the biological analyte. A detector can be configured to detect a signal from the at least one probe coupled to the biological analyte, thereby analyzing the biological analyte.

Provided are methods for biological sample processing and analysis. A method can comprise providing a substrate configured to rotate. The substrate can comprise an array having immobilized thereto a biological analyte. A solution comprising a plurality of probes may be directed, via centrifugal force, across the substrate during rotation of the substrate, to couple at least one of the plurality of probes with the biological analyte. A detector can be configured to detect a signal from the at least one probe coupled to the biological analyte, thereby analyzing the biological analyte.

The present invention provides a new and improved multiplexed oligonucleotide detection method based on the nanopore technology with one or more probes containing a sequence with complementarity to the target oligonucleotide, a terminal extension at the probe's 3′ terminus, 5′ terminus, or both termini and a label attached to the terminus. The improved probes and probe sets enable sensitive, selective, and direct multiplex detection, differentiation and quantification of distinct target oligonucleotides such as miRNAs. The inventive detection method may also be employed as a non-invasive and cost-effective diagnostic method based on miRNA levels in the patient's tissue sample.

The present invention provides a new and improved multiplexed oligonucleotide detection method based on the nanopore technology with one or more probes containing a sequence with complementarity to the target oligonucleotide, a terminal extension at the probe's 3′ terminus, 5′ terminus, or both termini and a label attached to the terminus. The improved probes and probe sets enable sensitive, selective, and direct multiplex detection, differentiation and quantification of distinct target oligonucleotides such as miRNAs. The inventive detection method may also be employed as a non-invasive and cost-effective diagnostic method based on miRNA levels in the patient's tissue sample.

Provided herein are compositions and methods for sequencing using at least altering electrical characteristics of polymer ridges. In some examples, the bridges may span the space between first and second electrodes and may include a single-stranded conjugated polymer chain. A plurality of nucleotides may be coupled to corresponding labels. A polymerase may be coupled to the bridge and may add nucleotides to a first polynucleotide using at least a sequence of a second polynucleotide. The labels corresponding to those nucleotides respectively may alter an electrical characteristic of the conjugated polymer chain. Detection circuitry may detect a sequence in which the polymerase adds the nucleotides to the first polynucleotide using at least changes in an electrical signal through the bridge, the changes being responsive to the respective alterations of hybridization using the labels corresponding to those nucleotides.

Provided herein are compositions and methods for sequencing using at least altering electrical characteristics of polymer ridges. In some examples, the bridges may span the space between first and second electrodes and may include a single-stranded conjugated polymer chain. A plurality of nucleotides may be coupled to corresponding labels. A polymerase may be coupled to the bridge and may add nucleotides to a first polynucleotide using at least a sequence of a second polynucleotide. The labels corresponding to those nucleotides respectively may alter an electrical characteristic of the conjugated polymer chain. Detection circuitry may detect a sequence in which the polymerase adds the nucleotides to the first polynucleotide using at least changes in an electrical signal through the bridge, the changes being responsive to the respective alterations of hybridization using the labels corresponding to those nucleotides.

Provided herein are compositions and methods for sequencing using at least altering electrical characteristics of polymer ridges. In some examples, the bridges may span the space between first and second electrodes and may include a single-stranded conjugated polymer chain. A plurality of nucleotides may be coupled to corresponding labels. A polymerase may be coupled to the bridge and may add nucleotides to a first polynucleotide using at least a sequence of a second polynucleotide. The labels corresponding to those nucleotides respectively may alter an electrical characteristic of the conjugated polymer chain. Detection circuitry may detect a sequence in which the polymerase adds the nucleotides to the first polynucleotide using at least changes in an electrical signal through the bridge, the changes being responsive to the respective alterations of hybridization using the labels corresponding to those nucleotides.