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This report describes a reversible colourimetric and on–off–on module of fluorescent chemosensor for selective cascade recognition of Cu2+ and with unique output optical response in aqueous solution. On the other hand, F−, Cl−, Br−, I−, CH3COO−, HSO4−, ClO4−, CN− and SCN− did not induce significant changes in fluorescence. Moreover, the colour change in chemosensor LH by response of this colourimetric chemosensor can be visualised by naked eye. These fluctuations in spectral response, under electronic behaviour, can be viewed to mimic as IMPLICATION logic gate.

A reversible and water-soluble 2,4-dimethyl-7-amino-1,8-naphthyridine (ZR) was synthesized to fluorescently sense CN− in water. Interestingly, the deprotonation reaction between cyanide and the primary amine would block the intramolecular charge transfer of the electron donor and acceptor, thus, affecting the ICT efficiency and optical properties of the sensing system.

Objectives. Traditional Chinese medicine (TCM) therapy for nonerosive reflux disease (NERD) remains controversial. The aim of this study was to evaluate the efficacy and safety of TCM regimens in NERD treatment. Methods. Randomized controlled trials (RCTs) of TCM treatment for NERD through September 31, 2017, were systematically identified in PubMed, Wanfang Data, CNKI, VIP, CBM, Ovid, Web of Science, and Cochrane Library databases. Quality assessment was performed by employing the Cochrane Risk of Bias assessment tool. Results. A total of 725 and 719 patients in 14 RCTs were randomly divided into TCM alone and conventional Western medicine groups, respectively. The clinical total effective rate of the TCM group was markedly higher than that of the single proton pump inhibitors (PPIs) or Prokinetics therapy group (RR = 1.19, 95% CI = 1.07–1.31, and P = 0.0008), while it was comparable to that of the combination of PPIs and Prokinetics therapy group (RR = 1.14, 95% CI = 1.00–1.29, and P = 0.05). Compared with Western medicine group, the TCM group showed improved symptom relief through a reduced RDQ score (SMD = −0.91; 95% CI = −1.68–−0.15; and P = 0.02). Additionally, TCM clearly decreased the recurrence rate (RR = 0.38, 95% CI = 0.28–0.52, and P < 0.00001). Adverse events, such as constipation, sickness, fever, abdominal distension, and stomach noise, were slight for both the TCM and Western medicine groups and disappeared after the easement of pharmacological intervention; in particular, TCM possessed fewer side effects. Conclusion. Compared with PPIs or Prokinetics therapy alone, TCM single therapy can better improve the clinical total effective rate and symptom relief and decrease the recurrence rate and adverse events in the treatment of NERD. Our results suggest that TCM will be a promising alternative therapy for NERD patients in the future.

A copillar[5]arene derivative with different repeating units was synthesized by co-oligomerization of different alkyl ethers. Copillar[5]arene-based supramolecular polymer gel was formed by a self-inclusion complexing in acetonitrile. The supramolecular polymer gel was driven by the CH· π interactions, and presented two phases as time went on, and finally, constructed the supramolecular organic framework. Notably, the supramolecular polymer gel showed reversible gel-sol phase transitions upon heating and cooling. Meanwhile, the transparent films formed by the supramloecular gel show the potential application in the field of anti-acid rain materials.

Chemosensor (CS1) was designed and synthesized by simple green chemistry procedure. CS1 exhibited both colorimetric and fluorescence turn-off responses for cyanide (CN(-)) ion in aqueous solution. The probe showed an immediate visible color changes from yellow to colorless and green fluorescence disappearance when CN(-) was added. The mechanism of chemosensor reaction with CN(-) was studied using (1)HH NMR and (13)C NMR spectroscopies and mass spectrometry. Moreover, test strips based on the sensor were fabricated, which served as convenient and efficient CN(-) test kits.

A 2-(quinolin-2-ylmethylene) malononitrile (6) chemosensor has been designed and synthesized. The fluorogenic properties of 6 toward different anions and metal ions were investigated in DMSO/H2O (1 : 9, v/v) solution. Probe 6 exhibits high selectivity and sensitivity (5.09 × 10−8 M) to CN− as fluorescence “off–on” behavior through Michael addition. Moreover, the in situ formed 6-CN− is further utilized to sense the Cu2+ through complexation reaction with high selectivity and fluorescence quenching performance in aqueous water. Probe 6 has selectively detected CN− in real water sample, and on test strips. The FTIR, 1HNMR and ESI-MS spectroscopy supported the proposed mechanism of interaction.

A new functionalized copillar[5]arene derivative containing one 1,4-bis(hexadecyl)benzene unit and four 1,4-dimethoxybenzene units has been synthesized and revealed to present self-assembly driven by C–H⋯π and cation⋯π interactions in CD3CN solution, giving a constructed supramolecular polymer gel accompanied by aggregation-induced enhanced emission (AIEE) of fluorescence. When adding a surfactant bearing hexadecylpyridinium chloride into the gel, the electron-poor compound penetrated into the rich-electron cavity of DCP5-16, forming host–guest complexation and causing fluorescence quenching due to the electron transfer. This approach may open up routes to novel stimuli–responsive supramolecular materials.

A simple colorimetric and fluorimetric ‘On–Off’ sensor L (3,3′-dimethyl -[1,1′-biphenyl]-4,4′-diyl)bis(azanylylidene)bis(methanylylidene)bis(naphthalen-2-ol) for Cu2+ ions bearing o-tolidine substituents has been designed and synthesised, and exhibits significant fluorimetric and colorimetric response for Cu2+ in DMSO/H2O (8:2, v/v) HEPES buffer (pH 7.2) solution. The detection limit of the sensor towards Cu2+ is 7.25 × 10− 8 M and the association constant Ka of 9.86 × 104 M− 1 was determined. Furthermore, other anions, including Fe3+, Hg2+, Ag+, Ca2+, Co2+, Ni2+, Cd2+, Pb2+, Zn2+, Cr3+ and Mg2+ have almost no influence on the probe's behaviour. Test strips based on the sensor L were fabricated, which could act as convenient and efficient Cu2+ test kits.

A water-soluble, non-sulfur, 2,4-dimethyl-7-amino-1,8-naphthyridine (Z1) chemosensor was synthesized to fluorescently sense Hg2+ in water. The single crystal structure of the sensor confirmed the synthesis results. The detection limit of the sensor towards Hg2+ was 8.859 × 10−8 M, which indicates its high detection sensitivity. The immediate response of Z1 to Hg2+ provided a real-time detection method.

A simple Schiff base sensor (L1) derived from N-(1-naphthyl) ethylenediamine dihydrochloride was designed and synthesised by simple chemistry procedures. The sensor exhibited a visible colour change observed by both colorimetric and fluorimetric responses for cyanide ion in aqueous solution. The detection of cyanide was performed via the nucleophilic attack of cyanide anion on the imine group of the sensor with a 1 : 1 binding stoichiometry. Moreover, test strips based on the sensor were fabricated, which served as convenient and efficient CN− test kits and the sensor L1 is a good way to detect hydrogen cyanide in aqueous extracts of sprouting potatoes.