See our DARPA Team's new Nature Communications article on molecular memory: https://www.nature.com/articles/s41467-020-14455-1 . We have stored and retrieved the largest files to date using a combination of intelligent synthesis, automation, and machine learning in non-biological molecules! Here's the related blog: https://bioengineeringcommunity.nature.com/users/345076-jacob-k-rosenstein/posts/59230-multicomponent-molecular-memory.