Long-term radiological and pulmonary function abnormalities at 3†years after COVID-19 hospitalisation: a longitudinal cohort study.

BACKGROUND: This study aimed to evaluate the longitudinal progression of residual lung abnormalities (ground-glass opacities, reticulation and fibrotic-like changes) and pulmonary function at 3 years following coronavirus disease 2019 (COVID-19). METHODS: This prospective, longitudinal cohort study enrolled COVID-19 survivors who exhibited residual lung abnormalities upon discharge from two hospitals. Follow-up assessments were conducted at 6 months, 12 months, 2 years and 3 years post-discharge, and included pulmonary function tests, 6-min walk distance (6MWD), chest computed tomography (CT) scans and symptom questionnaires. Non-COVID-19 controls were retrospectively recruited for comparative analysis. RESULTS: 728 COVID-19 survivors and 792 controls were included. From 6 months to 3 years, there was a gradual improvement in reduced diffusing capacity of the lung for carbon monoxide (D LCO <80% predicted: 49% versus 38%; p=0.001), 6MWD (496 versus 510 m; p=0.002) and residual lung abnormalities (46% versus 36%; p<0.001), regardless of disease severity. Patients with residual lung abnormalities at 3 years more commonly had respiratory symptoms (32% versus 16%; p<0.001), lower 6MWD (494 versus 510 m; p=0.003) and abnormal D LCO (57% versus 27%; p<0.001) compared with those with complete resolution. Compared with controls, the proportions of D LCO impairment (38% versus 17%; p<0.001) and respiratory symptoms (23% versus 2.2%; p<0.001) were significantly higher in the matched COVID-19 survivors at the 3-year follow-up. CONCLUSIONS: Most patients exhibited improvement in radiological abnormalities and pulmonary function over time following COVID-19. However, more than a third continued to have persistent lung abnormalities at the 3-year mark, which were associated with respiratory symptoms and reduced diffusion capacity.

Highly Luminescent Chiral Carbon Nanohoops via Symmetry Breaking with a Triptycene Unit: Bright Circularly Polarized Luminescence and Size-Dependent Properties.

Chiral carbon nanohoops with both high fluorescence quantum yield and large luminescence dissymmetry factor are essential to the development of circularly polarized luminescence (CPL) materials. Herein, the rational design and synthesis of a series of highly fluorescent chiral carbon nanohoops TP-[8-13]CPPs via symmetry breaking with a chiral triptycene motif is reported. Theoretical calculations revealed that breaking the symmetry of nanohoops causes a unique size-dependent localization in the highest occupied molecular orbitals (HOMOs) and the lowest unoccupied molecular obtitals (LUMOs) as the increasing of sizes, which is sharply different from those of [n]cycloparaphenylenes. Photophysical investigations demonstrated that TP-[n]CPPs display size-dependent emissions with high fluorescence quantum yields up to 92.9% for TP-[13]CPP, which is the highest value among the reported chiral conjugated carbon nanohoops. The high fluorescence quantum yields are presumably attributed to both the unique acyclic, and radial conjugations and high radiative transition rates, which are further supported by theoretical investigations. Chiroptical studies revealed that chiral TP-[n]CPPs exhibit bright CPL with CPL brightness up to 100.5 M-1 cm-1 for TP-[11]CPP due to the high fluorescence quantum yield. Importantly, the investigations revealed the intrigued size-dependent properties of TP-[n]CPPs with regards to (chir)optical properties, which follow a nice linear relationship versus 1/n. Such a nice linear relationship is not observed in other reported conjugated nanohoops including CPPs.

Structurally Diverse Pyrene-decorated Planar Chiral [2,2]Paracyclophanes with Tunable Circularly Polarized Luminescence between Monomer and Excimer.

We reported the synthesis of a series of structurally diverse CPL-active molecules, in which pyrene units were installed to chiral pm/po-[2,2]PCP scaffolds either with or without a triple bond spacer for pm/po-PCP-P1 and pm/po-PCP-P2, respectively. The X-ray crystallographic analyses revealed that these pyrene-based [2,2]PCP derivatives exhibited diverse structures and crystal packings in the solid phases. The pyrene-based [2,2]PCP derivatives exhibit various (chir)optical properties in organic solutions, depending on their respective structures. In a mixture of dioxane and water, pm/po-PCP-P1 emit green excimer fluorescence, whereas pm/po-PCP-P2 emit blue one. The chiroptical investigation demonstrated that Rp-pm-PCP-P1 and Rp-pm-PCP-P2 exhibited completely opposite CD and CPL signals even they possess the same chiral Rp-[2,2]PCP core. The same argument also holds for other chiral pyrene-based [2,2]PCP derivatives. The theoretical calculation revealed that these unusual phenomena were attributed to different orientation between transition electric dipole moments and the magnetic dipole moments originating from the presence or absence of a triple bond spacer. These pyrene-based [2,2]PCP derivatives display various colours and fluorescence emissions in the solid state and PMMA films, possibly due to the different packings as observed in the crystal structure. Moreover, these compounds also can interact with perylene diimide through π-π interactions, leading to near-white fluorescence.

Longitudinal Assessment of Chest CT Findings and Pulmonary Function after COVID-19 Infection.

Background Information on pulmonary sequelae and pulmonary function 2 years after recovery from SARS-CoV-2 infection is lacking. Purpose To longitudinally assess changes in chest CT abnormalities and pulmonary function in individuals after SARS-CoV-2 infection. Materials and Methods In this prospective study, participants discharged from the hospital after SARS-CoV-2 infection from January 20 to March 10, 2020, were considered for enrollment. Participants without chest CT scans at admission or with complete resolution of lung abnormalities at discharge were excluded. Serial chest CT scans and pulmonary function test results were obtained 6 months (June 20 to August 31, 2020), 12 months (December 20, 2020, to February 3, 2021), and 2 years (November 16, 2021, to January 10, 2022) after symptom onset. The term interstitial lung abnormality (ILA) and two subcategories, fibrotic ILAs and nonfibrotic ILAs, were used to describe residual CT abnormalities on follow-up CT scans. Differences between groups were compared with the χ2 test, Fisher exact test, or independent samples t test. Results Overall, 144 participants (median age, 60 years [range, 27-80 years]; 79 men) were included. On 2-year follow-up CT scans, 39% of participants (56 of 144) had ILAs, including 23% (33 of 144) with fibrotic ILAs and 16% (23 of 144) with nonfibrotic ILAs. The remaining 88 of 144 participants (61%) showed complete radiologic resolution. Over 2 years, the incidence of ILAs gradually decreased (54%, 42%, and 39% of participants at 6 months, 12 months, and 2 years, respectively; P < .001). Respiratory symptoms (34% vs 15%, P = .007) and abnormal diffusing capacity of lung for carbon monoxide (43% vs 20%, P = .004) occurred more frequently in participants with ILAs than in those with complete radiologic resolution. Conclusion More than one-third of participants had persistent interstitial lung abnormalities 2 years after COVID-19 infection, which were associated with respiratory symptoms and decreased diffusion pulmonary function. Chinese Clinical Trial Registry no. ChiCTR2000038609 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by van Beek in this issue.

Shape-Persistent Triptycene-Derived Pillar[6]arenes: Synthesis, Host-Guest Complexation, and Enantioselective Recognitions of Chiral Ammonium Salts.

Construction of macrocyclic hosts with a novel structure and excellent property has emerged as an intriguing undertaking for the past few years. Here, we reported the synthesis of shape-persistent triptycene-derived pillar[6]arene (TP[6]). The single crystal structure analysis revealed that the macrocyclic molecule adopts a hexagonal structure, featuring a helical and electron-rich cavity capable of encapsulating electron-deficient guests. In order to obtain chiral TP[6] from an enantiomerically pure triptycene building block, an efficient resolution of chiral triptycene was successfully developed through introducing chiral auxiliaries into triptycene skeletons. The 1H NMR and isothermal titration calorimetry investigations demonstrated that chiral TP[6] exhibited enantioselectivity toward four pairs of chiral guests containing a trimethylamino group, implying a significant promising application in area of enantioselective recognition.

Chiral Carbon Nanorings: Synthesis, Properties and Hierarchical Self-assembly of Chiral Ternary Complexes Featuring a Narcissistic Chiral Self-Recognition for Chiral Amines.

We report the synthesis and chiroptical properties of novel chiral carbon nanorings Sp-/Rp-[12]PCPP containing a planar chiral [2.2]PCP unit, and demonstrate that Sp-/Rp-[12]PCPP can not only host crown ether 18-Crown-6 to form ring-in-ring complexes with a binding constant 3.35×103  M-1 , but also accommodate the complexes of 18-Crown-6 and S/R-protonated amines to form homochiral S@Sp-/R@Rp- and heterochiral S@Rp-/R@Sp- ternary complexes, displaying significantly larger binding constants of up to 3.31×105  M-1 depending on the chiral guests. Importantly, homochiral S@Sp-/R@Rp- ternary complexes exhibit an enhanced CD signal, while the heterochiral S@Rp-/R@Sp- ones have a constant CD signal compared with the chiral carbon nanorings, respectively, which suggests that homochiral S@Sp-/R@Rp- ternary complexes display a highly narcissistic chiral self-recognition for S/R-protonated chiral amines, respectively. Finally, the chiral ternary complexes can be further applied to determine the ee values of chiral guests. The findings highlight a new application of carbon nanorings in supramolecular sensors, beyond the common recognition of π-conjugated molecules.

1-year outcomes in hospital survivors with COVID-19: a longitudinal cohort study.

BACKGROUND: The full range of long-term health consequences of COVID-19 in patients who are discharged from hospital is largely unclear. The aim of our study was to comprehensively compare consequences between 6 months and 12 months after symptom onset among hospital survivors with COVID-19. METHODS: We undertook an ambidirectional cohort study of COVID-19 survivors who had been discharged from Jin Yin-tan Hospital (Wuhan, China) between Jan 7 and May 29, 2020. At 6-month and 12-month follow-up visit, survivors were interviewed with questionnaires on symptoms and health-related quality of life (HRQoL), and received a physical examination, a 6-min walking test, and laboratory tests. They were required to report their health-care use after discharge and work status at the 12-month visit. Survivors who had completed pulmonary function tests or had lung radiographic abnormality at 6 months were given the corresponding tests at 12 months. Non-COVID-19 participants (controls) matched for age, sex, and comorbidities were interviewed and completed questionnaires to assess prevalent symptoms and HRQoL. The primary outcomes were symptoms, modified British Medical Research Council (mMRC) score, HRQoL, and distance walked in 6 min (6MWD). Multivariable adjusted logistic regression models were used to evaluate the risk factors of 12-month outcomes. FINDINGS: 1276 COVID-19 survivors completed both visits. The median age of patients was 59·0 years (IQR 49·0-67·0) and 681 (53%) were men. The median follow-up time was 185·0 days (IQR 175·0-198·0) for the 6-month visit and 349·0 days (337·0-361·0) for the 12-month visit after symptom onset. The proportion of patients with at least one sequelae symptom decreased from 68% (831/1227) at 6 months to 49% (620/1272) at 12 months (p<0·0001). The proportion of patients with dyspnoea, characterised by mMRC score of 1 or more, slightly increased from 26% (313/1185) at 6-month visit to 30% (380/1271) at 12-month visit (p=0·014). Additionally, more patients had anxiety or depression at 12-month visit (26% [331/1271] at 12-month visit vs 23% [274/1187] at 6-month visit; p=0·015). No significant difference on 6MWD was observed between 6 months and 12 months. 88% (422/479) of patients who were employed before COVID-19 had returned to their original work at 12 months. Compared with men, women had an odds ratio of 1·43 (95% CI 1·04-1·96) for fatigue or muscle weakness, 2·00 (1·48-2·69) for anxiety or depression, and 2·97 (1·50-5·88) for diffusion impairment. Matched COVID-19 survivors at 12 months had more problems with mobility, pain or discomfort, and anxiety or depression, and had more prevalent symptoms than did controls. INTERPRETATION: Most COVID-19 survivors had a good physical and functional recovery during 1-year follow-up, and had returned to their original work and life. The health status in our cohort of COVID-19 survivors at 12 months was still lower than that in the control population. FUNDING: Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences, the National Natural Science Foundation of China, the National Key Research and Development Program of China, Major Projects of National Science and Technology on New Drug Creation and Development of Pulmonary Tuberculosis, the China Evergrande Group, Jack Ma Foundation, Sino Biopharmaceutical, Ping An Insurance (Group), and New Sunshine Charity Foundation.

Nanosized Carbon Macrocycles Based on a Planar Chiral Pseudo Meta-[2.2]Paracyclophane.

Structural designs combining cycloparaphenylenes (CPPs) backbone with planar chiral [2.2]paracyclophane ([2.2]PCP) lead to optical-active chiral macrocycles with intriguing properties. X-ray crystal analysis revealed aesthetic necklace-shaped structures and size-dependent packages with long-range channels. The macrocycles exhibit unique photophysical properties with high fluorescence quantum yield of up to 82 %, and the fluorescent color varies with ring size. In addition, size-dependent chiroptical properties with moderately large CPL dissymmetry factor of 10-3 and CPL brightness in the range of 30-40 M-1 cm-1 were observed.

Six-month Follow-up Chest CT Findings after Severe COVID-19 Pneumonia.

Background Little is known about the long-term lung radiographic changes in patients who have recovered from coronavirus disease 2019 (COVID-19), especially those with severe disease. Purpose To prospectively assess pulmonary sequelae and explore the risk factors for fibrotic-like changes in the lung at 6-month follow-up chest CT of survivors of severe COVID-19 pneumonia. Materials and Methods A total of 114 patients (80 [70%] men; mean age, 54 years ± 12) were studied prospectively. Initial and follow-up CT scans were obtained a mean of 17 days ± 11 and 175 days ± 20, respectively, after symptom onset. Lung changes (opacification, consolidation, reticulation, and fibrotic-like changes) and CT extent scores (score per lobe, 0-5; maximum score, 25) were recorded. Participants were divided into two groups on the basis of their 6-month follow-up CT scan: those with CT evidence of fibrotic-like changes (traction bronchiectasis, parenchymal bands, and/or honeycombing) (group 1) and those without CT evidence of fibrotic-like changes (group 2). Between-group differences were assessed with the Fisher exact test, two-sample t test, or Mann-Whitney U test. Multiple logistic regression analyses were performed to identify the independent predictive factors of fibrotic-like changes. Results At follow-up CT, evidence of fibrotic-like changes was observed in 40 of the 114 participants (35%) (group 1), whereas the remaining 74 participants (65%) showed either complete radiologic resolution (43 of 114, 38%) or residual ground-glass opacification or interstitial thickening (31 of 114, 27%) (group 2). Multivariable analysis identified age of greater than 50 years (odds ratio [OR]: 8.5; 95% CI: 1.9, 38; P = .01), heart rate greater than 100 beats per minute at admission (OR: 5.6; 95% CI: 1.1, 29; P = .04), duration of hospital stay greater than or equal to 17 days (OR: 5.5; 95% CI: 1.5, 21; P = .01), acute respiratory distress syndrome (OR: 13; 95% CI: 3.3, 55; P < .001), noninvasive mechanical ventilation (OR: 6.3; 95% CI: 1.3, 30; P = .02), and total CT score of 18 or more (OR: 4.2; 95% CI: 1.2, 14; P = .02) at initial CT as independent predictors for fibrotic-like changes in the lung at 6 months. Conclusion Six-month follow-up CT showed fibrotic-like changes in the lung in more than one-third of patients who survived severe coronavirus disease 2019 pneumonia. These changes were associated with an older age, acute respiratory distress syndrome, longer hospital stays, tachycardia, noninvasive mechanical ventilation, and higher initial chest CT score. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Wells et al in this issue.

Super metal hydrogels constructed from a simple tripodal gelator and rare earth metal ions and its application in highly selective and ultrasensitive detection of histidine.

A series of stable super metal hydrogels (TP-Ms, M = Tb3+, Eu3+, La3+ and Ce3+) with a low critical gelation concentration (2.28 × 10-3 M, 0.1%) was successfully constructed by forming hierarchical assemblies of a tripodal gelator (TP) with rare earth metal ions (Tb3+, Eu3+, La3+ and Ce3+). Interestingly, the super metal hydrogels TP-Eu and TP-La show a specific and ultrasensitive response to histidine (His). The addition of a series of amino acids into the metal hydrogels TP-Eu and TP-La showed that only His could induce distinct fluorescent enhancement for TP-Eu and TP-La, while other amino acids did not significantly interfere with the His sensing process. The LODs of super metal-hydrogel TP-Eu and TP-La for His are (1.83-1.94) × 10-9 and (1.83-1.85) × 10-9 M, respectively. In addition, constructing super supramolecular metal hydrogels by hierarchical assemblies of an easily synthesized tripodal gelator and rare earth metal ions is a novel and efficient approach to the design and development of multi-functional super supramolecular metal hydrogel-based materials.

Pillar[5]arene-based spongy supramolecular polymer gel and its properties in multi-responsiveness, dye sorption, ultrasensitive detection and separation of Fe3.

Herein, a novel way to design and construct multi-functional spongy supramolecular polymer gels through an easy to make tripodal guest (TA) and a naphthalimide functionalized-pillar[5]arene host (AP5) has been developed. According to this approach, a novel pillar[5]arene-based supramolecular polymer gel (SHG) was constructed via multi-non-covalent interactions such as host-guest inclusion, C-Hπ, ππ and hydrogen bonds and so on. Interestingly, the SHG exhibits a spongy structure and strong aggregation induced emission (AIE). Furthermore, the SHG also exhibited multi-responsiveness toward outer stimuli such as heating-cooling, pH, competitive agents and mechanical. More importantly, the SHG xerogel shows separation properties for Fe3+, methyl orange, methylene blue and sudan I dyes. The separation rates of SHG xerogel for Fe3+ ions and organic dyes can reach up to 99.8%. Simultaneously, the SHG could ultrasensitively detect Fe3+ (LOD is 0.9 nM). In addition, a thin film based on SHG was also prepared, which was confirmed to be a convenient test kit for detecting Fe3+.

Aggregation-induced emission supramolecular organic framework (AIE SOF) gels constructed from tri-pillar[5]arene-based foldamer for ultrasensitive detection and separation of multi-analytes.

In this study, a novel aggregation-induced emission supramolecular organic framework (AIE SOF) with ultrasensitive response, termed FSOF, was constructed using a tri-pillar[5]arene-based foldamer. Interestingly, benefiting from the noise signal shielding properties of FSOF as well as the competition between the cationπ and ππ interactions, the FSOF shows an ultrasensitive response for multi-analytes, such as Fe3+, Hg2+ and Cr3+. The limits of detection (LODs) of the FSOF for Fe3+, Hg2+ and Cr3+ are in the range of 9.40 × 10-10-1.86 × 10-9. More importantly, the xerogel of FSOF exhibits porous mesh structures, which could effect high-efficiency separation above metal ions from their aqueous solution, with adsorption percentages in the range 92.39-99.99%. In addition, by introducing metal ions into the FSOF, a series of metal ions coordinated supramolecular organic frameworks (MSOFs) were successfully constructed. Moreover, MSOFs show selective fluorescence "turn on" ultrasensitive detection CN- (LOD = 2.12 × 10-9) and H2PO4- (LOD = 1.78 × 10-9). This is a novel approach to construct SOFs through a tri-pillar[5]arene-based foldamer, and also provides a new way to achieve ultrasensitive detection and high-efficiency separation.

A novel bis-component AIE smart gel with high selectivity and sensitivity to detect CN-, Fe3+ and H2PO4.

A novel bis-component AIE-gel TG was facilely constructed from two "easy-to-synthesize" tripodal gelators by a simple host-guest self-assembly process. Interestingly, the TG shows strong aggregation-induced emission (AIE) and could be used for highly efficient and sensitive detection and separation of ions (CN-, Fe3+ and H2PO4-). The LODs (limits of lowest detection) of TG for CN-, Fe3+ and H2PO4- are in the range of 4.93 × 10-9-7.80 × 10-8 M. Meanwhile, the xerogel of TG could adsorb and separate Fe3+ from aqueous solutions, and the adsorption rate is 96%. In addition, a thin film based on the TG could act as a convenient test kit for the detection of CN- and Fe3+. What is more, the TG-Fe film could not only be used as an erasable secure fluorescent display material, but also as a convenient reversible H2PO4- test kit.

A novel AIE-based supramolecular polymer gel serves as an ultrasensitive detection and efficient separation material for multiple heavy metal ions.

Recently, ultrasensitive stimuli-responsive materials have received extensive attention due to their high sensitivity and wide applications. Herein, we report a novel approach to design ultrasensitive responsive materials by rationally introducing the aggregation-induced emission (AIE) effect into supramolecular polymer gels. According to this approach, by rationally introducing self-assembly moieties and a fluorophore, the obtained gelator DNS can act as an AIEgen; it showed strong AIE after aggregating into the supramolecular polymer gel GDNS. More interestingly, because the aggregation of DNS led to amplification of the detective signal, the AIE-based supramolecular polymer gel GDNS could ultrasensitively detect the heavy metal ions Hg2+, Cu2+, and Fe3+ by a signal amplification mechanism; the lowest detection limits reached 10-11 M. In addition, the xerogel of GDNS could adsorb and separate Hg2+, Cu2+, and Fe3+ from aqueous solution with favourable adsorption properties, and the adsorption rates ranged from 94.70% to 99.37%. Furthermore, the gel GDNS could act as a convenient test kit for Hg2+, Cu2+, and Fe3+ as well as a smart fluorescent display material.

A novel supramolecular AIE π-gel for fluorescence detection and separation of metal ions from aqueous solution.

A novel supramolecular aggregation induced emission (AIE) π-gel (ONT) was constructed by using a functionalized trimesic amide (TCP) molecule assembled with a bis-pyridine functionalized naphthalene diimide (ND) molecule using a non-covalent interaction. The ONT showed strong AIE at 468 nm. Furthermore, the ONT could detect and adsorb ferric (Fe3+) or cupric (Cu2+) ions from water. Meanwhile, a thin film based on supramolecular AIE π-gel ONT was prepared, which could be used as a fluorescent security display material for detecting Fe3+ or Cu2+. Thus, the AIE π-gel ONT shows potential for practical applications in efficient multi-analyte detection and separation and as a fluorescent display material.

A bi-component supramolecular gel for selective fluorescence detection and removal of Hg2+ in water.

A bi-component supramolecular gel (RQ) was successfully constructed by the assembly of the gelators 4-aminophenyl functionalized naphthalimide derivative (R) and tri-(pyridine-4-yl)-functionalized trimesic amide (Q) in DMSO-H2O (6.1 : 3.9, v/v) binary solution. The gel RQ exhibits excellent self-healing capacity. Interestingly, the RQ could fluorescently detect and reversibly remove Hg2+ from water through cation-π interactions with high selectivity, efficient adsorption and quick response. The limit of lowest detection (LOD) of the RQ for Hg2+ is 4.52 × 10-8 M and the separation ratio is 91.14%. Moreover, the RQ could be efficiently recycled and regenerated with little loss via a simple treatment by I-. Notably, thin films based on RQ and RQ + Hg2+ were prepared, which could serve as convenient and efficient test tools for the detection of Hg2+ and I-, respectively. This work provided an efficient method and novel supramolecular gel material for the separation and detection of Hg2+.

Pillar[5]arene-Based Supramolecular Organic Framework with Multi-Guest Detection and Recyclable Separation Properties.

The selective detection and separation of target ions or molecules is an intriguing issue. Herein, a novel supramolecular organic framework (SOF-THBP) was constructed by bis-thioacetylhydrazine functionalized pillar[5]arenes. The SOF-THBP shows a fluorescent response for Fe3+ , Cr3+ , Hg2+ and Cu2+ ions. The xerogel of SOF-THBP shows excellent recyclable separation properties for these metal ions and the absorption rates were up to 99.29 %. More interestingly, by rationally introducing these metal ions into the SOF-THBP, a series of metal-ion-coordinated SOFs (MSOFs) such as MSOF-Fe, MSOF-Hg and MSOF-Cu were constructed. These metal ions coordinated MSOFs could selectively sense F- , Br- , and l-Cys, respectively. The detection limits of these MSOFs for F- , Br- and l-Cys were about 10-8  m.

Acylhydrazone functionalized benzimidazole-based metallogel for the efficient detection and separation of Cr3.

Chromium(iii) is a kind of microelement and can be converted to the more toxic chromium(vi), which is a carcinogen, by redox cycling. Thus, the development of novel materials for the detection and removal of Cr3+ is a very important issue. A novel metallogel chemosensor (BMG-Fe) based on functionalized benzimidazole (BM) and Fe3+ was constructed, which could fluorescently detect and separate Cr3+. The detection limit of BMG-Fe for Cr3+ is 2.62 × 10-8 M, and it exhibited high sensitivity and selectivity for Cr3+. Meanwhile, the absorbing percentage of BMG-Fe for Cr3+ is 96.36%, indicating a high separation rate. Interestingly, the sensitivity and ingestion capacity of BMG-Fe for Cr3+ are better than that of the simple organogel (BMG). So, the metallogel BMG-Fe could be utilized for the efficient removal of heavy metal ions from waste water.

A novel supramolecular polymer gel based on naphthalimide functionalized-pillar[5]arene for the fluorescence detection of Hg2+ and I- and recyclable removal of Hg2+via cation-π interactions.

The development of novel materials for the detection and removal of Hg2+ is a very important issue due to the acute toxicity of Hg2+. Herein, a novel supramolecular polymer P5BD-DPHB has been constructed by the collaboration of a naphthalimide functionalized-pillar[5]arene host (P5BD) and a bis-bromohexane functionalized-pillar[5]arene guest (DPHB). P5BD-DPHB could form a stable supramolecular gel (P5BD-DPHB-G). Interestingly, P5BD-DPHB-G shows selective fluorescent "turn-on" detection for Hg2+via cation-π interactions with high selectivity and sensitivity. Furthermore, the Hg2+ coordinated supramolecular gel P5BD-DPHB-HgG can detect I- successively. The detection limits for Hg2+ and I- are 1.65 × 10-9 and 1.84 × 10-8 mol L-1, respectively. Even more significantly, the xerogel of P5BD-DPHB-G could remove Hg2+ from aqueous solution with excellent recyclability and ingestion capacity, and with a Hg2+ removal rate of 98%.

Novel multi-analyte responsive ionic supramolecular gels based on pyridinium functionalized-naphthalimide.

A novel ionic supramolecular gel (is-G) is synthesized using N-(pyridinium-4-yl)-naphthalimide (G1) and n-pentanoic acid. By rationally introducing competitive coordination into is-G, two ion coordinated ionic supramolecular gels is-IG and is-FeG (coordinated with I- and Fe3+, respectively) are obtained. is-IG could fluorescently "turn-on" detect Hg2+ and l-Arg with specific selectivity, whereas, is-FeG could accurately identify l-Ser via fluorescence in water. Moreover, ion or amino acid responsive films based on these ionic supramolecular gels are prepared. These ionic supramolecular gels and films could act as multi-analyte detection materials as well as fluorescent display materials.