Scientists in China and the US have developed a novel storage medium made from silk proteins, an implantable material on which information can be written to, read from and erased.

The silk protein memory, capable of storing digital information as well as biological data such as blood biomarkers, has a capacity of 64GB per square inch and can operate under harsh conditions including bacterial contamination, high humidity, high magnetic fields and clinical-level gamma radiation.

The research work was a collaboration between scholars from Chinese Academy of Sciences (CAS), the University of Texas at Austin, and Stony Brook University.

Infrared light is used to etch information onto the silk, with nano probes used for focusing the light beams, according to the study.

“The biological compatibility of the silk drive is good and can be implanted into living organisms, such as the human body, which can be preserved for a long time or even forever,” Tiger Tao Hu from CAS’ Shanghai Institute of Microsystem and Information Technology, was quoted as saying by state-backed media The Global Times.

The information stored in the silk hard drive remained “safe and sound” even after 30 minutes of exposure to high level microwave radiation, according to Tao.

Two different types of the silk drive were implanted in two rats in a recent experiment. A cross-linked version, more resistant to harsh conditions, was retrieved a week later with the information “nearly intact”, according to a study published in the journal Nature Nanotechnology last week.

The information stored in the second version that was not cross-linked “largely disappeared due to the degradation of the silk substrate”, the journal said.

The silk drive is still in the proof-of-concept stage and “unlikely in the foreseeable future to match the speed and storage capacity of state-of-the-art solid-state devices at a competitive cost,” according to Chinese and US researchers, who promised “substantial improvements in the speed and storage capacity of silk drives”.

 - SCMP