Silkworm baby "spit" out of innovation in Shanghai

Silk scarves are made of silk silk. What constitutes silk? Recently, Professor Zhang Yaopeng and Professor Shao Huili from the State Key Laboratory of Fiber Materials Modification at Donghua University are in the internationally renowned journal "ACS Nano". In the full text, an important research result in the field of silk was published: the silk that has been inherited for thousands of years is actually assembled by ordering silk fibroin with a thickness of only 0.4 nm, which can be called "nano ribbon". The diameter of a silk in a silk scarf is approximately equal to the thickness of the 30,000 layers of silk fibroin nanofiber ribbons.

Nano ribbon

"The doctoral students in our team owe a system of sodium hydroxide/urea aqueous solution, and the silk is gradually stripped at a low temperature into a nanofiber ribbon with a thickness of about 0.4 nm and a width of about 27 nm, almost the thickness of the single layer of graphene. Compared with other silk fibroin nanofibers in the literature, the 'nano-ribbon' is the world's thinnest silk fibroin nanofiber belt." Professor Zhang Yaopeng said that the silk fibroin nanofiber belt can be self-assembled or ordered. Used as a reinforcing component or as a direct building unit, it is expected to produce silk fibroin-based materials with excellent performance or functionality, such as bone tissue engineering scaffolds, surgical sutures, ultra-thin flexible self-supporting transparent membranes, etc., which will be applied to biomedicine and biology in the future. The prospects in the fields of electronic interface, filtering, optics, imaging, etc. are very broad.

Professor Zhang Yaopeng believes that in addition to the efforts of the cattle to owe themselves, there is a great relationship with the construction of the Shanghai Science and Technology Center: "We prepared silk fibroin nanofibers using atomic force microscopy and transmission electron microscopy. It has been characterized, and its thickness can be explained to some extent, but the evidence is not sufficient. Therefore, we further directly characterized the silk fibroin nanofibril suspension by small angle X-ray scattering technology of Shanghai synchrotron radiation source (BL16B line station). The thickness of the microfibers analyzed is consistent with the results of atomic force microscopy and transmission electron microscopy. Shanghai Synchrotron Radiation Source has played a decisive role in the achievement of this scientific research."

Fluorescent silk

In addition to the "nano-ribbons", the research and development team of biomass materials led by Professor Zhang Yaopeng and Professor Shao Huili added rare earth infrared upconversion phosphors (UCPs) with low toxicity, good light penetration and good photochemical stability to artificial feed. The modified artificial diet was used to feed the silkworm, and the UCPs were introduced into the silk fibroin based on the silkworm bioreactor, and the fluorescent silk was successfully obtained.

Fluorescent silk not only has good biocompatibility, biodegradability and excellent mechanical properties, but also has special mark-tracking function, so it has great application prospects in medical fields such as bio-imaging. How to prepare silk with stable fluorescence performance by simple and environmentally friendly method has attracted great research interest. Professor Zhang Yaopeng introduced that the preparation of fluorescent silk by adding silkworms is not only environmentally friendly, but also easy to mass-produce. It provides a new idea for the development of multifunctional fluorescent silk, and some of the results of this experiment were completed in Shanghai. Microfocus line station (BL15U).

In the view of Professor Zhang Yaopeng, Donghua University has always stood at the forefront of research and development of advanced fiber in the world by promoting the industrialization of chemical fiber to solve the problem of dressing the people. Now we are looking forward to the ecology of Shanghai Kechuang. Circle ', let the silkworm baby 'spit' more innovative silk."