Extended XOR Algorithm with Biotechnology Constraints for Data Security in DNA Storage

Background: DNA storage is becoming a global research hotspot in recent years, and today, most research focuses on storage density and big data. The security of DNA storage needs to be observed. Some DNA-based security methods were introduced for traditional information security problems. However, few encryption algorithms considered the limitation of biotechnology and applied it for DNA storage. The difference between DNA cryptography and the traditional one is that the former is based on the limitation of biotechnology, which is unrelated to numeracy. Objective: An extended XOR algorithm (EXA) was introduced for encryption with constraints of biotechnology, which can solve the problems of synthesis and sequencing partly, such as GC content and homopolymer in DNA storage. Methods: The target file was converted by a quaternary DNA storage model to maximize the storage efficiency. The key file could be ‘anything’ converted into a DNA sequence by a binary DNA storage model to make the best utilization for the length of the key file. Results: The input files were encrypted into DNA storage and decrypted to error-free output files. Conclusion: This means error-free encryption DNA storage is feasible, and EXA paves the way for encryption in large-scale DNA storage.