Covalent organic frameworks (COFs) represent an emerging class of two- or three-dimensional crystalline porous materials with delicate control over topology, composition, and porosity. Here, we develop a new COF made up of 1,3,6,8-tetrakis­(p-formylphenyl)­pyrene (TFPPy) and 4,4′-diaminobenzophenone (DABP) that exhibits a rare one-dimensional (1D) structure. The resulting frameworks possess good crystallinity, comparatively high Brunauer–Emmett–Teller (BET) surface area (426 m2/g), and good thermal stability (360 °C). Impressively, this 1D COF shows strong fluorescence and can be used as an excellent H+ sensor in an acidic aqueous solution.

Covalent organic frameworks (COFs) have been extensively investigated due to their unique structure, porosity, and functionality. However, at the topological level, COFs remain as two‐dimensional (2D) or three‐dimensional (3D) structures, while COFs with one‐dimensional (1D) topology have not been systematically explored. In this work, we proposed a synthetic strategy for the construction of 1D‐COFs based on non‐linear edges and suitable high‐symmetry vertices. Compared with their 2D‐COFs counterparts, the 1D‐COFs with AIEgens located at the vertex of the frame exhibited enhanced fluorescence. The density functional theory (DFT) calculations revealed that the dimensional‐induced rotation restriction (DIRR) effect could spontaneously introduce additional non‐covalent interactions between the strip frames, which could substantially diminish non‐radiative transitions. This work also provides protocols for the design of 1D‐COFs and a guidance scheme for the synthesis of emitting COFs.

A water-stable and pH-independent sensor for qualitative and quantitative detection of nicotine in urine solution and living cell was successfully developed. This material, named MB@UiO-66-NH 2 , can be synthesized by encapsulating methylene blue (MB) with a well-known metal−organic framework (MOF) UiO-66-NH 2 through a simple impregnation method. The fluorescence intensity of the system was significantly enhanced when a certain amount of nicotine was added. In the meanwhile, MB is reduced by reductive nicotine to form leucomethylene blue (LB). The proposed sensor displayed excellent selectivity and sensitivity toward nicotine with limit of detection (LOD) of 0.98 μM, which is comparable or even better than that of the electrochemistry detecting methods for nicotine. The obvious enhancement and blue shift of the emission arise from the photoinduced electron transfer (PET) from LB to the UiO-66-NH 2 . The photophysical properties and the sensing applications of MB@ UiO-66-NH 2 suggest that this composite can be acted as a sensitive, selective, recyclable, and fluorogenic sensor for nicotine determination in urine solution and living cell.

The basolateral nucleus of the amygdala (BL) is thought to support numerous emotional behaviors through specific microcircuits. These are often thought to be comprised of feedforward networks of principal cells (PNs) and interneurons. Neither well-understood nor often considered are recurrent and feedback connections, which likely engender oscillatory dynamics within BL. Indeed, oscillations in the gamma frequency range (40 − 100 Hz) are known to occur in the BL, and yet their origin and effect on local circuits remains unknown. To address this, we constructed a biophysically and anatomically detailed model of the rat BL and its local field potential (LFP) based on the physiological and anatomical literature, along with in vivo and in vitro data we collected on the activities of neurons within the rat BL. Remarkably, the model produced intermittent gamma oscillations (∼50 − 70 Hz) whose properties matched those recorded in vivo, including their entrainment of spiking. BL gamma-band oscillations were generated by the intrinsic circuitry, depending upon reciprocal interactions between PNs and fast-spiking interneurons (FSIs), while connections within these cell types affected the rhythm’s frequency. The model allowed us to conduct experimentally impossible tests to characterize the synaptic and spatial properties of gamma. The entrainment of individual neurons to gamma depended on the number of afferent connections they received, and gamma bursts were spatially restricted in the BL. Importantly, the gamma rhythm synchronized PNs and mediated competition between ensembles. Together, these results indicate that the recurrent connectivity of BL expands its computational and communication repertoire.