Two kinds of shape-controllable and fluorescent supramolecular organic frameworks (cuboid or spheroid) are constructed hierarchically from CB[8] and tetraphenylethylene derivatives through host-guest interaction in water. These two fluorescent SOFs exhibit intriguing and varied photophysical properties, including large red-shifts (up to 82 nm) and stimuli-responsive behavior to competitive guest by binding with CB[8], the turn-on fluorescence of which is applied in cellular imaging.

Chiral framework materials have been developed for many applications including chiral recognition, chiral separation, asymmetric catalysis, and chiroptical materials. Herein, we report that an achiral cucurbit[8]uril‐based supramolecular organic framework (SOF‐1) with the dynamic rotational conformation of tetraphenylethene units can exhibit adaptive chirality to produce M‐SOF‐1 or P‐SOF‐1 with mirror‐image circular dichroism (CD) with gabs≈±10−4 and circularly polarized luminescence (CPL) with glum≈±10−4 induced by L‐/D‐phenylalanine in water, respectively. The chirality induction in CD (gabs≈−10−4) and CPL (glum≈−10−4) of P‐SOF‐1 from achiral SOF‐1 can be presented by using a small amount of adenosine‐5′‐triphosphate disodium (ATP) or adenosine‐5′‐diphosphate disodium (ADP) (only 0.4 equiv) in water. Furthermore, the adaptive chirality of SOF‐1 can be used to determine dipeptide sequences (e.g., Phe‐Ala and Ala‐Phe) and distinguish polypeptides/proteins (e.g., somatostatin and human insulin) with characteristic CD spectra. Therefore, achiral SOF‐1 as an ideal chiroptical platform with adaptive chirality may be applied to determine the enantiopurity of amino acids (e.g., L‐/D‐phenylalanine), develop aqueous CPL materials, and distinguish biological chiral macromolecules (e.g., peptides/proteins) via chirality induction in water.

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