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Abstract DNA has emerged as a promising material to address growing data storage demands. We recently demonstrated a structure-based DNA data storage approach where DNA probes are spatially oriented on the surface of DNA origami and decoded using DNA-PAINT. In this approach, larger origami structures could improve the efficiency of reading and writing data. However, larger origami require long single-stranded DNA scaffolds that are not commonly available. Here, we report the engineering of a novel longer DNA scaffold designed to produce a larger rectangle origami needed to expand the origami-based digital nucleic acid memory (dNAM) approach. We confirmed that this scaffold self-assembled into the correct origami platform and correctly positioned DNA data strands using atomic force microscopy and DNA-PAINT super-resolution microscopy. This larger structure enables a 67% increase in the number of data points per origami and will support efforts to efficiently scale up origami-based dNAM.
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An alternative approach to nucleic acid memory
Abstract DNA is a compelling alternative to non-volatile information storage technologies due to its information density, stability, and energy efficiency. Previous studies have used artificially synthesized DNA to store data and automated next-generation sequencing to read it back. Here, we report digital Nucleic Acid Memory (dNAM) for applications that require a limited amount of data to have high information density, redundancy, and copy number. In dNAM, data is encoded by selecting combinations of single-stranded DNA with (1) or without (0) docking-site domains. When self-assembled with scaffold DNA, staple strands form DNA origami breadboards. Information encoded into the breadboards is read by monitoring the binding of fluorescent imager probes using DNA-PAINT super-resolution microscopy. To enhance data retention, a multi-layer error correction scheme that combines fountain and bi-level parity codes is used. As a prototype, fifteen origami encoded with ‘Data is in our DNA!\n’ are analyzed. Each origami encodes unique data-droplet, index, orientation, and error-correction information. The error-correction algorithms fully recover the message when individual docking sites, or entire origami, are missing. Unlike other approaches to DNA-based data storage, reading dNAM does not require sequencing. As such, it offers an additional path to explore the advantages and disadvantages of DNA as an emerging memory material.
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- Award ID(s):
- 1807809
- PAR ID:
- 10223239
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 12
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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