Abstract: Selectively controllable cleavable linkers include electrochemically-cleavable linkers, photolabile linkers, thermolabile linkers, chemically-labile linkers, and enzymatically-cleavable linkers. Selective cleavage of individual linkers may be controlled by changing local conditions. Local conditions may be changed by activating electrodes in proximity to the linkers, exposing the linkers to light, heating the linkers, or applying chemicals. Selective cleaving of enzymatically-cleavable linkers may be controlled by designing the sequences of different sets of the individual linkers to respond to different enzymes. Cleavable linkers may be used to attach polymers to a solid substrate. Selective cleavage of the linkers enables release of specific polymers from the solid substrate. Cleavable linkers may also be used to attach protecting groups to the ends of growing polymers. The protecting groups may be selectively removed by cleavage of the linkers to enable growth of specific polymers.

Abstract: A data storage medium is disclosed comprising a two-dimensional (2D) support structure onto which artificially synthesized DNA molecules encoding digital information are placed and then covered with a protective layer. The 2D support structure is formed from a material such as metal foil, glass, or plastic. The 2D support structure may be functionalized with positively charged molecules to improve DNA adhesion. The DNA is protected from degradation by encapsulation in a protective layer of a non-reactive material such as silica or a thin layer of metal. A process for storing DNA on 2D support structures is also disclosed. Correlation of specific DNA molecules with a physical storage location on a 2D support structure provides geometric addressability for selective access to specific digital information.

Abstract: Polynucleotides such as DNA are stored inside vesicles formed from self-assembling membranes. The vesicles may be protocells, liposome, micelles, colloidosomes, proteinosomes, or coacervates. The vesicles may include surface functionalization to improve polynucleotide encapsulation and/or to bind polynucleotides having specific sequences. Encapsulation in vesicles provides protection for the polynucleotides. Additional protection is provided by addition of one or more stabilizers. The stabilizer may be nucleic-acid stabilizers that stabilize the polynucleotides or may be a protective structural layer around the vesicles such as a layer of silica. A process for stably storing polynucleotides in vesicles and a process for recovering stored polynucleotides from vesicles are both disclosed. The polynucleotides may be used for storage of digital information.

Abstract: A data storage medium is disclosed comprising a dried product formed by drying a salt solution dried together with artificially synthesized DNA molecules encoding digital information. The cation in the salt may be calcium, magnesium, lanthanum, or another cation. The anion in the salt may be chloride, phosphate, or another anion. The DNA is protected from degradation by drying with the salt. Stored DNA may be freed from the salt for sequencing or other analysis by mixing the dried product with a chelator. The dry product formed from DNA and a salt may contain more than 30% DNA by weight and degrade at rates that are less than a third of rate at which untreated DNA degrades.

Abstract: A data storage medium is disclosed comprising a substrate covered with alternating layers of a polycationic molecule and artificially synthesized DNA molecules encoding digital information. The magnetic substrate may be a metallic nanoparticle formed from a metal such as iron or cobalt. The polycationic molecule may be polyethyleneimine (PEI). The DNA is protected from degradation by encapsulation in silica. A process for stably storing DNA is also disclosed. Stored DNA may be freed from the silica for sequencing or other analysis by washing the silica-coated DNA with a buffered hydrogen fluoride solution. Storage densities of more than 7% DNA by weight are achieved on nanoparticles.

Abstract: Described herein are systems and methods for coupling environmental hazard detection and actuation of a wearable chemical sensor at a molecular level. The chemical sensor may be a wearable chemical sensor implemented as a powder, cream, lacquer or other wearable construct. The wearable chemical sensor may detect exposure to various environmental hazards and provide an analog means (e.g., a range of color changes) of indicating the level of environmental hazard exposure.