A Rule for Response Sensitivity of Structural-Color Photonic Colloids.

To mimic natural photonic crystals having color regulation capacities dynamically responsive to the surrounding environment, periodic assembly structures have been widely constructed with response materials. Beyond monocomponent materials with stimulus responses, binary and multiphase systems generally offer extended color space and complex functionality. Constructing a rule for predicting response sensitivity can provide great benefits for the tailored design of intelligently responsive photonic materials. Here, we elucidate mathematical relationships between the response sensitivity of dynamically structural-color changes and the location distances of photonic co-phases in three-dimensional Hansen space that can empirically express the strength of their interaction forces, including dispersion force, polarity force, and hydrogen bonding. Such an empirical rule is proven to be applicable for some typical alcohols, acetone, and acetic acid regardless of their molecular structures, as verified by angle resolution spectroscopy, in situ infrared spectroscopy, and molecular simulation. The theoretical method we demonstrate provides rational access to custom-designed responsive structural coloration.

Photonic Cellulose Films with Vivid Structural Colors: Fabrication and Selectively Chemical Response.

Recent advances in structural-color cellulose nanocrystal (CNC) materials have been made toward chemical sensing applications; however, such materials lack sufficient color chroma for naked-eye observation, and their selective recognition to given chemicals as well as the corresponding mechanism has rarely been reported. Here, a dopamine-infiltration and post-polymerization approach is proposed to construct vivid structural-color composite films. The chiral nematic structure of CNC enables the structural coloration, while the strong light absorption of the polymeric co-phase, polydopamine (PDA) enhances the color chroma and visibility. By controlling the PDA amount, the composite films can detect organic solvents quantitatively and selectively via visible color changes. From the viewpoint of the compatibility and similitude principle, notably, a critical solubility parameter distance (R0) between PDA and "active" solvents is defined with a three-dimensional Hansen solubility sphere; this well constructs a rule for the sensing selectivity of the chemochromic composite films. The findings pave the foundation for the design of colorimetric sensors with specifically testing objects.

Successful treatment of Rosai-Dorfman disease using in situ photoimmunotherapy.

Rosai-Dorfman disease is difficult to cure. In situ photoimmunotherapy combines local photothermal therapy with immunoadjuvant. In the present case report, a 39-year-old Chinese man with Rosai-Dorfman disease lesions below the left nostril and left preauricular region was treated with in situ photoimmunotherapy. The patient was treated with daily application of topical imiquimod (5%) and laser irradiations every 2 weeks for 8 weeks. After three cycles of treatment, the lesions improved markedly without adverse effects. Our results showed that in situ photoimmunotherapy can be used as an effective treatment for Rosai-Dorfman disease.