Spider silks are protein-based “biopolymer” filaments or threads secreted by specialized epithelial cells as concentrated soluble precursors of highly repetitive primary sequences. Spider dragline silk is a flexible, lightweight fiber of extraordinary strength and toughness comparable to that of synthetic high-performance fibers. We sought to “biomimic” the process of spider silk production by expressing in mammalian cells the dragline silk genes ( ADF-3 / MaSpII and MaSpI ) of two spider species. We produced soluble recombinant (rc)–dragline silk proteins with molecular masses of 60 to 140 kilodaltons. We demonstrated the wet spinning of silk monofilaments spun from a concentrated aqueous solution of soluble rc–spider silk protein (ADF-3; 60 kilodaltons) under modest shear and coagulation conditions. The spun fibers were water insoluble with a fine diameter (10 to 40 micrometers) and exhibited toughness and modulus values comparable to those of native dragline silks but with lower tenacity. Dope solutions with rc–silk protein concentrations >20% and postspinning draw were necessary to achieve improved mechanical properties of the spun fibers. Fiber properties correlated with finer fiber diameter and increased birefringence.

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TiO 2 loaded with crystalline nano silver (c-Ag/TiO 2 ) was successfully synthesized by a one-step low-temperature hydrothermal method in aqueous solution using tetra-n-butyl titanate and AgNO 3 as precursors. The structure and morphology were characterized by Auger electron spectroscopy (AES), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-Vis absorption spectra (UV-Vis) and fluorescence spectra (FS). The photocatalytic activity was tested with photocatalytic degradation of hydrogen sulfide (H 2 S) gas. The results show that the nano silver particles of Ag/TiO 2 prepared by the one-step lowtemperature hydrothermal method are crystalline, while they are amorphous when prepared by the conventional UV reduction deposition method (a-Ag/TiO 2 ). The photocatalytic activity of the c-Ag/TiO 2 prepared by the hydrothermal method was found to have a significant improvement for H 2 S degradation, being more than 2 times over that of the a-Ag/TiO 2 prepared by the conventional method.