Electrical detection methods are used to identify and further characterize single-molecule target analytes such as proteins and nucleic acids. A composition including a probe region and a tail region is contacted with a target analyte. The probe region specifically binds to the target analyte. The tail region is coupled to the probe region, and includes a nucleic acid template for polynucleotide synthesis. When conditions are such that polynucleotide synthesis occurs along the tail region, one hydrogen ion is released for every nucleotide that is incorporated into the tail region. A transistor such as an ISFET detects and measures changes in ion concentration, and these measurements can be used to identify the tail region and thus characterize the corresponding target analyte.

The present report relates to hybridizing single-stranded (ss-) oligonucleotides which entirely consist of locked nucleic acid (LNA) monomers. The present document shows hybridization experiments with pairs of entirely complementary ss-oligonucleotides which fail to form a duplex within a given time interval. The present report provides methods to identify such incompatible oligonucleotide pairs. In another aspect, the present report provides pairs of complementary ss-oligonucleotides which are capable of rapid duplex formation. The present report also provides methods to identify and select compatible oligonucleotide pairs. In yet another aspect the present report provides use of compatible oligonucleotide pairs as binding partners in binding assays, e.g. receptor-based assays.

The present report relates to hybridizing single-stranded (ss-) oligonucleotides which entirely consist of locked nucleic acid (LNA) monomers. The present document shows hybridization experiments with pairs of entirely complementary ss-oligonucleotides which fail to form a duplex within a given time interval. The present report provides methods to identify such incompatible oligonucleotide pairs. In another aspect, the present report provides pairs of complementary ss-oligonucleotides which are capable of rapid duplex formation. The present report also provides methods to identify and select compatible oligonucleotide pairs. In yet another aspect the present report provides use of compatible oligonucleotide pairs as binding partners in binding assays, e.g. receptor-based assays.

The present invention is directed to methods and compositions for adding tails of specific lengths to a substrate polynucleotide. The invention also contemplates methods and compositions for immobilization of tailed substrates to a solid support. The disclosure contemplates that the attenuator molecule is any biomolecule that associates with a tail sequence added to a substrate polynucleotide and controls the addition of a tail sequence to the 3′ end of the substrate polynucleotide. The sequence that is added to the substrate polynucleotide is referred to herein as a tail sequence, or simply a tail, and the process of adding a nucleotide to a substrate polynucleotide is referred to herein as tailing.

The present invention is directed to methods and compositions for adding tails of specific lengths to a substrate polynucleotide. The invention also contemplates methods and compositions for immobilization of tailed substrates to a solid support. The disclosure contemplates that the attenuator molecule is any biomolecule that associates with a tail sequence added to a substrate polynucleotide and controls the addition of a tail sequence to the 3′ end of the substrate polynucleotide. The sequence that is added to the substrate polynucleotide is referred to herein as a tail sequence, or simply a tail, and the process of adding a nucleotide to a substrate polynucleotide is referred to herein as tailing.

Provided are a method for constructing a library based on an RNA sample and uses thereof. The method includes: step 1 of subjecting the RNA sample to a reverse transcription reaction to obtain DNA-RNA hybrid strands; step 2 of performing reaction of the DNA-RNA hybrid strands with an endoribonuclease, a first DNA polymerase, a second DNA polymerase, and dATPs to obtain a double-stranded DNA added with dA-tail, where the first DNA polymerase has a 5′-3′ exonuclease activity and a 3′-5′ exonuclease activity, and the second DNA polymerase has no 3′-5′ exonuclease activity; step 3 of ligating the double-stranded DNA added with dA-tail and a sequencing adaptor to obtain a ligated product; and step 4 of subjecting the ligated product to PCR amplification to obtain a sequencing library.

Provided are a method for constructing a library based on an RNA sample and uses thereof. The method includes: step 1 of subjecting the RNA sample to a reverse transcription reaction to obtain DNA-RNA hybrid strands; step 2 of performing reaction of the DNA-RNA hybrid strands with an endoribonuclease, a first DNA polymerase, a second DNA polymerase, and dATPs to obtain a double-stranded DNA added with dA-tail, where the first DNA polymerase has a 5′-3′ exonuclease activity and a 3′-5′ exonuclease activity, and the second DNA polymerase has no 3′-5′ exonuclease activity; step 3 of ligating the double-stranded DNA added with dA-tail and a sequencing adaptor to obtain a ligated product; and step 4 of subjecting the ligated product to PCR amplification to obtain a sequencing library.

Provided herein are genetic circuits and cell state classifiers for detecting the microRNA profile of a cell. The cell state classifiers of the present disclosure are designed to incorporate multiple genetic circuits integrated together by transcriptional or translational control. Multiple inputs can be sensed simultaneously by coupling their detection to different portions of the genetic circuit such that the output molecule is produced only when the correct input profile of miRNAs is detected. The genetic circuits and cell state classifiers may be used in various applications (e.g., therapeutic or diagnostic applications).

The present invention relates to the field of pharmacogenomics and in particular to detecting the presence or absence of hypermethylated DNA. The detection of CpG methylation in marker DNA is useful for the diagnosis of cancers and the invention provides improved methods for this purpose. These improved methods allow in particular for a more sensitive detection of methylated marker DNA with high backgrounds of unmethylated marker DNA.

The present invention relates to the field of pharmacogenomics and in particular to detecting the presence or absence of hypermethylated DNA. The detection of CpG methylation in marker DNA is useful for the diagnosis of cancers and the invention provides improved methods for this purpose. These improved methods allow in particular for a more sensitive detection of methylated marker DNA with high backgrounds of unmethylated marker DNA.