Presented herein are transposase enzymes and reaction conditions for improved fragmentation and tagging of nucleic acid samples, in particular altered transposases and reaction conditions which exhibit improved insertion sequence bias, as well as methods and kits using the same.

Disclosed herein are methods for the generation of highly accurate nucleic acid libraries encoding for predetermined variants of a nucleic acid sequence. The nucleic acid sequence may encode for all or part of a TCR or a TCR-binding antigen. The degree of variation may be complete, resulting in a saturated variant library, or less than complete, resulting in a non-saturating library of variants. The variant nucleic acid libraries described herein may designed for further processing by transcription or translation. The variant nucleic acid libraries described herein may be designed to generate variant RNA, DNA and/or protein populations. Further provided herein are method for identifying variant species with increased or decreased activities, with applications in regulating biological functions and the design of therapeutics for treatment or reduction of a disease, such as cancer.

The invention combines the advantages of split and mix synthesis with the advantages of template directed synthesis. The method comprises the steps of: a) adding a linker molecule L to one or more reaction wells; b) adding a molecule fragment to each of said reaction wells; c) adding an oligonucleotide identifier to each of said reaction wells; d) subjecting said wells to conditions sufficient to allow said molecule fragments and said oligonucleotide identifiers to become attached to said linker molecule, or conditions sufficient for said molecule fragments to bind to other molecule fragments and sufficient for said oligonucleotide identifiers to bind to other oligonucleotide identifiers; e) combining the contents of said one or more reaction wells; and f) contacting the resulting bifunctional molecule(s) of step e) with one or more (oligonucleotide) templates each capable of hybridizing to at least one of the oligonucleotide identifiers added step c).

The present invention provides a method of solid-phase synthesis of DNA-encoded compound library. The method includes following steps: a) reacting solid carrier G-1 with linker molecule L-1 to prepare L-G-1; b) reacting DNA with linker molecule L-0 to prepare L-2; c) reacting L-G-1 with L-2 to prepare L-G-2; d) removing protection group of the L-G-2 and obtaining L-G-2-1; e) reacting the L-G-2-1 with synthetic building block and performing DNA encoding; and f) removing the solid carrier and obtaining the DNA-encoded compound library. Compared with the prior art, the present invention can complete post-treatment purification of the reaction only by filtration and irrigation processes for several times. The present invention is simple to operate, can shorten the production cycle of DNA encoded compound library with more than 50%, significantly increases the production efficiency and the unicity as well as the purity of the final products.

The present invention provides novel microfluidic substrates and methods that are useful for performing biological, chemical and diagnostic assays. The substrates can include a plurality of electrically addressable, channel bearing fluidic modules integrally arranged such that a continuous channel is provided for flow of immiscible fluids.

A nucleic acid patch method for amplifying target nucleic acid sequences in circulating free DNA or residual DNA samples where the defining ends of the target nucleic acid sequences are unknown.

A method of characterizing candidate agents including steps of (a) providing a library of candidate agents attached to nucleic acid tags; (b) contacting the library with a solid support to attach the candidate agents to the solid support, whereby an array of candidate agents is formed; (c) contacting the array with a screening agent, wherein one or more candidate agents in the array react with the screening agent; (d) detecting the array to determine that at least one candidate agent in the array reacts with the screening agent; (e) sequencing the nucleic acid tag to determine the tag sequences attached to candidate agents in the array; and (f) identifying the at least one candidate agent in the array that reacts with the screening agent based on the tag sequence that is attached to the at least one candidate agent.

A method of characterizing candidate agents including steps of (a) providing a library of candidate agents attached to nucleic acid tags; (b) contacting the library with a solid support to attach the candidate agents to the solid support, whereby an array of candidate agents is formed; (c) contacting the array with a screening agent, wherein one or more candidate agents in the array react with the screening agent; (d) detecting the array to determine that at least one candidate agent in the array reacts with the screening agent; (e) sequencing the nucleic acid tag to determine the tag sequences attached to candidate agents in the array; and (f) identifying the at least one candidate agent in the array that reacts with the screening agent based on the tag sequence that is attached to the at least one candidate agent.

The disclosure relates a method for constructing a plasma Deoxyribonucleic acid (DNA) sequencing library. The method includes: extracting a plasma DNA; making the plasma DNA ligate to a sequencing linker, and purifying a ligation product; performing Polymerase Chain Reaction (PCR) amplification for the purified ligation product, purifying the PCR amplification product, and obtaining the plasma DNA sequencing library, wherein, the method does not include the step of performing 5-terminus phosphorylation for the plasma DNA. The kit provided by the disclosure includes: a reagent which ligates a plasma DNA to a sequencing linker, including the sequencing linker, a ligase and a ligation buffer; and reagents and instruments for purifying the ligation product; a reagent which performs PCR amplification for a purified ligation product, and reagents and instruments for purifying the PCR amplification product; wherein, the kit does not include the reagent which performs 5-terminus phosphorylation for the plasma DNA.

Disclosed herein include systems, methods, compositions, and kits for preserving and/or recovering RNA from fixed and/or permeabilized cells, for example for single cell analysis. In some embodiments, the fixed and/or permeabilized cells are for measuring intracellular target (e.g., protein) expression.