The invention is directed to methods for synthesizing oligonucleotides direction on biomolecules or cells living or fixed. In some embodiments, template-free enzymatic synthesis is implemented under biological conditions with successive cycles of (i) enzymatic addition of a 3′-O-blocked nucleoside triphosphate and (ii) enzymatic deblocking of the incorporated nucleotide to regenerate a free 3′ hydroxyl. The invention has applications in single-cell cDNA library construction and analysis.

Provided herein, in some embodiments, are devices, systems and methods for high-throughput single-cell polyomics (e.g., genomic, epigenomic, proteomic and/or phenotypic profile) analyses.

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.

This disclosure provides methods for preparing a sequencing library including the steps of providing a template nucleic acid sequence, dNTPs, dUTP, a primer, a polymerase, a dUTP excising enzyme, and a plurality of beads including oligonucleotide adapter sequence segments; amplifying the template nucleic acid with the polymerase, dNTPs, dUTP and random hexamer to provide a complementary nucleic acid sequence including occasional dUTPs; and excising the incorporated dUTPs with the dUTP excising enzyme to provide nicks in the complementary nucleic acid sequence to provide a sequencing library.

A system for nucleic acid sequencing is provided. The system comprises a sequencing device configured to expose a tagged polynucleotide comprising a combinatorial barcode sequence and a sample polynucleotide to sequential nucleotide flows, each flow comprising one species of nucleotide and the sequential flows being in a predetermined order based on the species of nucleotide such that exposing of the tagged polynucleotide to the sequential nucleotide flows causes incorporations of nucleotides from the sequential nucleotide flows into the tagged polynucleotide over the barcode sequence The sequencing device is configured to detect a series of signals over the barcode sequence resulting from the incorporations, wherein the predetermined order of nucleotide flows comprises a repetition of a flow order motif that is based on a sequence motif. The system comprises a computing device configured to resolve the detected series of signals to determine the combinatorial barcode sequence.

Disclosed herein are methods for producing high density cellular arrays. In some embodiments, the methods comprise: providing a sample comprising a plurality of cells; and introducing the plurality of cells in the sample into microwells of a microwell array to produce a cellular array, wherein the microwell array comprises 500 or more microwells per inch.sup.2, and wherein 25% or more of the microwells of the cellular array comprise a single cell. The disclosed methods can be used for producing a high density synthetic particle array and a high density reagent array.

The invention is directed to methods for synthesizing oligonucleotides directly on biomolecules or cells living or fixed. In some embodiments, template-free enzymatic synthesis is implemented under biological conditions with successive cycles of (i) enzymatic addition of a 3′-O-blocked nucleoside triphosphate and (ii) enzymatic deblocking of the incorporated nucleotide to regenerate a free 3′ hydroxyl. The invention has applications in single-cell cDNA library construction and analysis.

The invention provides methods for stably immobilizing nucleic acid tracers onto surfaces of products and objects. This method is applied for the identification and authentication of the marked object or product. The present invention further provides specific coated articles and their use in product verification; processes for manufacturing such coated articles, methods for the verification of the coated article, methods for the quantification of the coated article blending, and products suitable for such verification and quantification method.

The present disclosure provides methods and systems for generation of compositions comprising two or more sets of molecules. Compositions herein may comprise sets of molecules of different types. Sets of molecules may be generated by attachment to supports. Different types of molecules may be used to generate a large number of unique molecules. One or more types of molecules may be used to identify one or more additional types of molecules. Compositions of the present disclosure may be used in, for example, nucleic acid sequencing.

The invention is directed to methods for synthesizing oligonucleotides direction on biomolecules or cells living or fixed. In some embodiments, template-free enzymatic synthesis is implemented under biological conditions with successive cycles of (i) enzymatic addition of a 3′-O-blocked nucleoside triphosphate and (ii) enzymatic deblocking of the incorporated nucleotide to regenerate a free 3′ hydroxyl. The invention has applications in single-cell cDNA library construction and analysis.