The helical chirality and self-assembling structures of an unnatural polymer, poly(p-ethynylbenzoyl-l-valine) (1), are readily manipulated by a simple environmental perturbation of pH change. The amino acid appendages of l-valine create an asymmetric force field, inducing the polyacetylene backbones to helically rotate, and form intra- and interchain hydrogen bonds, stabilizing the screw-sense conformation of the polymer chains. The polymer exhibits a large Cotton effect in methanol, which decreases with an increase in pH upon addition of KOH into the polymer solution. The change in the chain helicity is reversible:  the unfolded polymer chains refold back to their original helical conformations when the solutions are neutralized. Natural evaporation of the methanol solutions of 1 on mica gives long, bundled nanofibers of macromolecular assemblies; in contrast, evaporation of the methanol/KOH solutions yields short, unraveled nanofibers with sizes of roughly single macromolecular chains. The ionization of the carboxy groups of the valine moieties by KOH breaks the hydrogen bonds, and the entropy-driven randomization leads to the observed chain helicity attenuation. The electrical repulsion between the polyelectrolyte chains carrying the negatively charged carboxylate ions disassembles the macromolecular association, resulting in the formation of the nanofibers of single chain dimension.

In this work, a morpholine-functionalized aggregation-induced emission luminogen (AIEgen), AIE-LysoY, is reported for lysosomal imaging and autophagy visualization. To attain outstanding imaging contrast, AIE-LysoY is equipped with excited state intramolecular proton transfer (ESIPT) characteristic. AIE-LysoY provides a new platform for lysosome visualization with good biocompatibility, large Stokes shift, superior signal-to-noise ratio, and high photostability.

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The first example of an AIE interfacial material is developed, with a high PCE of 8.94% being achieved for the TPE-2 modified conventional PC71BM:PTB7-based PSC.

The self-assemblying behaviors of L-alanine methyl ester-containing polyphenylacetylene (PPA-Ala, in Chart 1 ) were investigated upon the evaporation of its solvent on mica and on air/water interfaces. The introduction of chiral amino acid attachments to the polyphenylacetylene backbone induced a helical conformation of the backbone, which was stabilized by various noncovalent interactions, especially hydrophobic effect and hydrogen bonds. The helicity of the polymer was further amplified in its higher-order self-assemblies as the formation of helical fibers on the surface of mica upon natural evaporation of its THF solution. By LB technique, the polymer chains were guided to form ordered parallel ridges and highly aligned, with their helical conformation still remaining. The reorganization of the chiral polymer chains on air/water interface was associated with the additional hydrophobic effect of PPA-Ala on an air/water interface. The polymer backbones had to adopt different arrangements to minimize their contact with water, and this adjustment led to the formation of aligned polymer ridges under proper surface pressure.

The use of natural biological materials as templates to construct novel hierarchical inorganic materials is an emerging area due to their unique and complex microstructures. [1] Compare to artificial templates, biological materials are hierarchical, abundant, complex, renewable, and environmentally benign. So far, several types of biological materials such as diatoms, [2] bacteria, [3,4] pollen, [5] cornstarch, [6] chitin, [7] and wood [8,9] have been utilized in order to prepare hierarchical inorganic materials.Among them, wood has highly anisotropic cellular structures, which can be used as a hierarchical template to generate novel ceramics with micro-, meso-, and macrostructures. Con- COMMUNICATIONS

A simple process for fast fabrication of thin films with biomimetic morphological structures from a group of linear homopolymers is developed. Natural evaporation of tetrahydrofuran, chloroform, and hexane-dichloromethane solutions of poly(phenylacetylene)s that contain amino acid and ethylene glycol moieties under ambient conditions instantly produces three-dimensional porous films with structural patterns reminiscent of honeycombs and radiolarian shells. Morphological analysis by optical and electronic microscopy suggests that vesicles of the amphiphilic polymers serve as building blocks in the self-organization to the biomimetic structures.

Multiple stimuli-responsive fluorescent materials are still in high demand owing to academic significance and potential applications. Designing a novel molecule with multiple stimuli-responsive properties is a hard work due to...