A rewritable optical storage medium of silk proteins using near-field nano-optics


Nanoscale lithography and information storage in biocompatible materials offer possibilities for applications such as bioelectronics and degradable electronics for which traditional semiconductor fabrication techniques cannot be used. Silk fibroin, a natural protein renowned for its strength and biocompatibility, has been widely studied in this context. Here, we present the use of silk film as a biofunctional medium for nanolithography and data storage. Using tip-enhanced near-field infrared nanolithography, we demonstrate versatile manipulation and characterize the topography and conformation of the silk in situ. In particular, we fabricate greyscale and dual-tone nanopatterns with full-width at half-maximum resolutions of ~35 nm, creating an erasable ‘silk drive’ that digital data can be written to or read from. As an optical storage medium, the silk drive can store digital and biological information with a capacity of ~64 GB inch−2 and exhibits long-term stability under various harsh conditions. As a proof-of-principle demonstration, we show that this silk drive can be biofunctionalized to exhibit chromogenic reactions, resistance to bacterial infection and heat-triggered, enzyme-assisted decomposition.

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Fig. 1: In situ patterning and characterization of the silk drive using TNINL.
Fig. 2: Mechanisms of TNINL.
Fig. 3: TNINL-mediated analogue and digital patterning of the silk drive.
Fig. 4: Writing and erasing data on the silk drive.
Fig. 5: High degree of robustness and biologically relevant functionalities of the silk drive.

Data availability

The data that support the findings of this study are available online at figshare (https://doi.org/10.6084/m9.figshare.12466034) and from the corresponding authors upon reasonable request.


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This material was based upon work supported by the National Science Foundation under grant no. CMMI-1563422. The University of Texas authors also acknowledge support from the Department of Mechanical Engineering. The Stony Brook University authors acknowledge support from the National Science Foundation under grant no. DMR-1904576, grant no. CMMI-1562915 and SBU-BNL SEED grant. T.H.T.’s group acknowledges support from the following: National Science and Technology Major Project from the Minister of Science and Technology of China (grant nos. 2018AAA0103100, 2020AAA0130100), National Natural Science Foundation of China (grant nos. 61574156, 61904187, 51703239, 51703238, 61605233), Scientific Instrument and Equipment Development Project of the Chinese Academy of Sciences (grant no. YJKYYQ20170060), National Science Fund for Excellent Young Scholars (grant no. 61822406), Shanghai Outstanding Academic Leaders Plan (grant no. 18XD1404700), Shanghai Sailing Program (grant nos. 19YF1456700, 17YF1422800), Key Research Program of Frontier Sciences, CAS (grant no. ZDBS-LY-JSC024), Youth Innovation Promotion Association CAS (grant no. 2019236) and Xinwei Star Project (grant no. Y91QDA1001). We thank Y. Mao, Z. Shi and J. Zhong from Huashan Hospital of Fudan University in Shanghai for their assistance with all animal experiments.

Author information




T.H.T., M.K.L. and W. Lee conceived the idea. T.H.T., M.K.L., W. Lee and Z.Z. designed the experiments. W. Lee, Z.Z., N.Q., J.J. and K.L. performed the experiments. M.K.L. and X.C. performed the simulation study. T.H.T., W. Lee, Z.Z., M.K.L., X.C., N.Q., J.J., K.L. and W. Li analysed the data. T.H.T., M.K.L., W. Lee, Z.Z., X.C. and W. Li wrote the paper. All authors discussed the results and provided comments for the manuscript.

Corresponding authors

Correspondence to Zhitao Zhou or Mengkun Liu or Tiger H. Tao or Wei Li.

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Supplementary information

Supplementary Information

Supplementary Notes 1–3 and Supplementary Figs. 1–20.

Supplementary Audio 1

Original audio encoded on silk.

Supplementary Audio 2

Recalled audio.

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Lee, W., Zhou, Z., Chen, X. et al. A rewritable optical storage medium of silk proteins using near-field nano-optics. Nat. Nanotechnol. (2020). https://doi.org/10.1038/s41565-020-0755-9

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