Data storage is a concern since there are limitations in the capacity of current hard drives. With DNA molecules as carriers of huge amounts of biological information, scientists are determining whether these DNA molecules can be utilized to store huge amount of data. However, new research shows that DNA is not the only thing when it comes to the possibility of storing data.
Brown University scholars discovered that there is a possibility in storing and retrieving data in artificial metabolomes--arrays of liquid mixtures that contain amino acids, sugars, and other kinds of small molecules. The findings of the research showed that there is a possibility in encoding kilobyte-scale image files into metabolite solutions and process the information one more time. Their research findings were published in the journal PLOS One.
"This is a proof-of-concept that we hope makes people think about using wider ranges of molecules to store information," said Jacob Rosenstein, a professor in Brown's School of Engineering and senior author of the study. "In some situations, small molecules like the ones we used here can have even greater information density than DNA."
The use of DNA has a benefit when it comes to metabolites reacting with each other to form new compounds. This enables molecular systems not only to store data but also to manipulate it to perform computations within metabolite mixtures.
The need for greater storage capacity is the reason behind molecular computing. It is estimated that global data would reach up to 3 septillion bits of data by 2040. The challenge is great when it comes to limited chip-grade silicon to perform the storing, searching, and processing of these data through the use of traditional semiconductor chips. Brown University engineers and chemists have teamed up to create a variety of techniques through small molecules in creating new information systems.
The team aimed to determine if it possible to use artificial metabolomes as storage devices. "In biology, a metabolome is the full array of molecules an organism uses to regulate its metabolism," according to Phys.
"It's not hard to recognize that cells and organisms use small molecules to transmit information, but it can be harder to generalize and quantify," said Eamonn Kennedy, a postdoctoral associate at Brown and first author of the study. "We wanted to demonstrate how a metabolome can encode precise digital information."
The scientists devised their own artificial metabolomes. They used different molecular combinations with small liquid mixtures. One bit of digital data is encoded through the presence or absence of a particulate metabolite. The number of bits that a mixture has a capacity is dependent on the number of molecule kinds in the artificial metabolome. The scientists devised libraries of six and 12 metabolites with each mixture having the capacity of six or 12 bits. Small metal plates are placed with thousands of mixtures. A liquid-handling robot places the contents and arrangement of the droplets which encodes the desired data.
Drying of plates is done which leaves tiny spots of metabolite molecules that carry digital data. A mass spectrometer then reads the data that has the capacity to identify the metabolites present at each spot on the plate and decode the data.
"The researchers used the technique to successfully encode and retrieve a variety of image files of sizes up to 2 kilobytes. That's not big compared to the capacity of modern storage systems, but it's a solid proof-of-concept, the researchers say. And there's plenty of potential for scaling up. The number of bits in a mixture increases with the number of metabolites in an artificial metabolome, and there are thousands of known metabolites available for use," according to Phys.
The method has various limitations including loss or error in data when the metabolites interact chemically with each other.
"Using molecules for computation is a tremendous opportunity, and we are only starting to figure out how to take advantage of it," said Brenda Rubenstein, a Brown assistant professor of chemistry and co-author of the study.
"Research like this challenges what people see as being possible in molecular data systems," Rosenstein said. "DNA is not the only molecule that can be used to store and process information. It's exciting to recognize that there are other possibilities out there with great potential."
