Implantable Transient Soluble Silk Protein Memory Developed by Shanghai Institute of Microsystems: Supports Multimodal Information Storage Encryption

IT House news on April 18, according to the Chinese Academy of Sciences, transient soluble memory is an important part and information storage medium in skin electronics and implantable devices. The device needs to have stable stability while achieving controllable degradation. Storage and encryption capabilities. With the rapid increase in the type and quantity of sensor integration, the current storage performance of transient soluble memory is difficult to meet the requirements of various information types and high information storage. It is urgent to seek further breakthroughs in memory mechanism, material and structure.

Following the development of the world’s first rewritable “silk hard disk” in 2020, Tao Hu’s team, a researcher at the Shanghai Institute of Microsystems and Information Technology, Chinese Academy of Sciences, once again challenged the core issues in the field of transient soluble memory and innovatively developed fibroin-based multilayer implantable transient memory (Figure 1). The memory adopts a new memory structure, which integrates three different information types of memory cells, namely resistive memristor, terahertz metamaterial, and optical diffractive element, through process optimization to achieve vertical high-density integration, and realize electrical, electromagnetic and Synchronous stable storage of optical information. The use of a memory material system composed of fibroin with adjustable solubility properties and degradable metals (magnesium, aluminum) not only ensures that each layer of memory cells has good electrical and optical properties, but also enables the memory to gradually degrade layer by layer and multi-layer fast. Various controllable degradation modes such as degradation, controllable layer number degradation in selected areas, etc. The combination of multimodal information encoding and multiple degradation modes improves the encryption capability and information storage capacity of transient memory, and only 16 units can make the richness of information storage reach 10⁵⁵ order of magnitude; the prepared 4×4 array transient soluble memory prototype realizes alphabet encoding, 16-bit binary encoding demonstration and verification codec example, thanks to the film formation uniformity and precise controllable degradation ability of silk protein, the memory The information misreading rate is low and the robustness is strong, which meets the requirements of multi-modal information storage and high-stability storage. On this basis, the subcutaneous implantation experiment in mice further verified the feasibility and biosafety of the layer-by-layer degradation of the transient memory in vivo. The excellent biocompatibility of silk protein does not cause tissue immune response. This indicates that the new multi-level transient soluble memory will play an important role in the fields of implantable devices and chips, in vivo information storage and biological electronic tags.

On April 8, the related research results were published in Advanced Materials under the title A Hierarchically Encoded Data Storage Device with Controlled Transiency. The research work is supported by the National Key R&D Program, the National Natural Science Foundation of China Outstanding Youth Science Fund Project, the Shanghai Yangfan Program, and the Youth Innovation Promotion Association of the Chinese Academy of Sciences.

Paper link:https://onlinelibrary.wiley.com/doi/full/10.1002/adma.202201035