The detection of volatile aliphatic aldehydes is of significance because of their chemical toxicity, physical volatility and widespread applications in chemical industrial processes. In this work, the direct detection of aliphatic aldehydes is tackled using a pillar[5]arene-based fluorescent supramolecular polymer with vaporchromic behavior. Thin films with strong orange-yellow fluorescence are prepared by coating the linear supramolecular polymer on glass sheets.When the thin films are exposed to aliphatic aldehydes with different carbon chain lengths, they can selectively sensing nbutyraldehyde (C 4 ) and caprylicaldehyde (C 8 ), accompanied by fluorescence quenching, indicating that the supramolecular polymer is a highly selective vapochromic response material for aliphatic aldehydes with long alkyl chains.

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Enzyme-responsive nanomaterials are emerging as important candidates for bioanalytical and biomedical applications due to their good biocompatibilities and sensitivities. However, the lack of promising operation platforms compatible with enzyme responsiveness greatly limits the scope and functionality of smart materials. Herein, we report the design and synthesis of a naphthalene-functionalized organoplatinum­(II) metallacycle 1 by means of coordination-driven self-assembly, which is subsequently exploited as the organometallic platform to enable enzyme-responsive supramolecular materials. Specifically, a [2 + 2] self-assembled metallacycle 1 first self-assembles into nanosheets in aqueous solution, which can further transform into vesicles with the introduction of β-cyclodextrin (β-CD) because of the formation of a bola-type supramolecular amphiphile β-CD-1. Interestingly, these vesicles show rare α-amylase responsiveness, as demonstrated by structurally transforming back into nanosheets after the addition of α-amylase to their solutions due to the enzyme-induced degradation of cyclodextrins. We also demonstrate the potential application of the self-assembled vesicles in amylase-responsive controlled release.

Macrocyclic molecule‐based host–guest systems, which provide contributions for the design and construction of functional supramolecular structures, have gained increasing attention in recent years. In particular, platinum(II) metallacycle‐based host–guest systems provide opportunities for chemical scientists to prepare novel materials with various functions and structures due to the well‐defined shapes and cavity sizes of platinum(II) metallacycles. However, the research on platinum(II) metallacycle‐based host–guest systems has been given little attention. In this article, we demonstrate the host–guest complexation between a platinum(II) metallacycle and a polycyclic aromatic hydrocarbon molecule, naphthalene. Taking advantage of metallacycle‐based host–guest interactions and the dynamic property of reversible Pt coordination bonds, a [2]rotaxane is efficiently prepared by employing a template‐directed clipping procedure. The [2]rotaxane is further applied to the fabrication of an efficient light‐harvesting system with multi‐step energy transfer process. This work comprises an important supplement to macrocycle‐based host–guest systems and demonstrates a strategy for efficient production of well‐defined mechanically interlocked molecules with practical values.

Aspartic acid and glutamic acid show critical impact in the central nervous system as excitatory neurotransmitters. The selective detection of aspartic acid and glutamic acid has a wide range of potential applications in the field of biomedicine. In this work, we report the highly selective detection of L‐Aspartic acid (L‐Asp) and L‐Glutamic acid (L‐Glu) in water is achieved by using a fluorescent nanoparticle constructed by a water‐soluble pillar[5]arene‐based host‐guest interactions. These nanoparticles show strong fluorescent emission in water. After the addition of L‐Asp or L‐Glu to a solution of the fluorescent nanoparticles, these nanoparticles transformed to nanosheets with weak fluorescent emission, resulting the highly selective detection of aspartic acid and glutamic acid in water. The detection limits of the fluorescent nanoparticles toward L‐Asp and L‐Glu were calculated to be 2.09×10−7 M and 4.03×10−7 M, respectively. This work provide an efficiency way for highly sensitive detection of L‐Asp and L‐Glu in water.