Chromogenic fusion proteins as alternative textiles dyes.

The widespread adoption of fast fashion has led to a significant waste problem associated with discarded textiles. Using proteins to color textiles can serve as a sustainable alternative to chemical dyes as well as reduce the demand for new raw materials. Here, we explore the use of chromogenic fusion proteins, consisting of a chromoprotein and a carbohydrate-binding module (CBM), as coloring agents for cellulose-based textiles such as cotton. We examined the color properties of chromoproteins AeBlue, SpisPink and Ultramarine alone and fused to CBM under various conditions. AeBlue, SpisPink and Ultramarine exhibited visible color between pH 4-9 and temperatures ranging from 4 to 45℃. Fusing CBM Clos from Clostridium thermocellum and CBM Ch2 from Trichoderma reesei to the chromoproteins had no effect on the chromoprotein color properties. Furthermore, binding assays showed that chromoprotein fusions did not affect binding of CBMs to cellulosic materials. Cotton samples bound with Ultramarine-Clos exhibited visible purple color that faded progressively over time as the samples dried. Applying 10% 8000 polyethylene glycol to cotton samples markedly preserved the color over extended periods. Overall, this work highlights the potential of chromoprotein-CBM fusions for textile dying which could be applied as a color maintenance technology or for reversible coloring of textiles for events or work wear, contributing to sustainable practices and introducing new creative opportunities for the industry.

Investigating the highest melting temperature materials: A laser melting study of the TaC-HfC system.

TaC, HfC and their solid solutions are promising candidate materials for thermal protection structures in hypersonic vehicles because of their very high melting temperatures (>4000 K) among other properties. The melting temperatures of slightly hypostoichiometric TaC, HfC and three solid solution compositions (Ta1-xHfxC, with x = 0.8, 0.5 and 0.2) have long been identified as the highest known. In the current research, they were reassessed, for the first time in the last fifty years, using a laser heating technique. They were found to melt in the range of 4041-4232 K, with HfC having the highest and TaC the lowest. Spectral radiance of the hot samples was measured in situ, showing that the optical emissivity of these compounds plays a fundamental role in their heat balance. Independently, the results show that the melting point for HfC0.98, (4232 ± 84) K, is the highest recorded for any compound studied until now.