Abstract: This paper utilized electronic single-fiber strength tester and Raman spectrometer to conduct testing and research on the spider silks of four spider species, namely Parasteatoda tepidariorum, Uloborus guangxiensis, Asiancoelotes plancyi and Paracoelotes luctuosus, in order to explore the relationship between their properties and structures. The results showed that the four spider silks had similar mechanical properties. Their Raman spectra overlapped or were close at certain peak positions, indicating that they belonged to different families and genera but had similar amino acid sequences and structures. The silk of Parasteatoda tepidariorum exhibited relatively high strength and elastic modulus with good load-bearing capacity. The silk of Uloborus guangxiensis had a high elongation rate, with its main advantages lying in toughness and deformation ability, which could maintain structural integrity under large deformation. The strength and elongation rate of the silks of Asiancoelotes plancyi and Paracoelotes luctuosus were relatively low, but they had a certain degree of toughness and achieved a good balance between strength and toughness. By comparing the peak intensity and characteristic peaks of the Raman spectra of the four kinds of spider silks, the subtle differences in their molecular structures could be deteremined. Raman spectroscopy could effectively analyze the protein structure of spider silk, and the reproducibility of the spectra was good.

Key words: spider silk, Raman spectrum, mechanical property, protein structure