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A novel method was developed for the sensitive and visual detection of p-phenylenediamine (PPD) via immobilizing the target specie PPD on dialdehyde cellulose membrane (DCM) followed by the reaction with salicylaldehyde. The obtained solid fluorescent membrane (S-PPD-DCM) emitted yellow fluorescence under 365 nm UV light. DCM was not only used as a solid matrix but also played a vital role in the enrichment of PPD. Experimental variables influencing the fluorescence signal were investigated and optimized. Under the optimum conditions, a detection limit of 5.35 μg L−1 was obtained and two linear ranges were observed at 10–100 and 100–1000 μg L−1, respectively. Moreover, the fluorescence of the resultant membrane can still be visualized by naked eye when PPD concentration was 50 μg L−1. The detection of PPD was hardly affected by the coexistence of 1 mg L−1 of o-phenylenediamine, m-phenylenediamine or p henylamine , exhibiting good selectivity. The developed method involved in a two-step Schiff base reaction and enhanced the fluorescence emission via blocking nonradiative intramolecular rotation decay of the excited molecules. It was applied to determine the PPD in spiked hair dye with satisfactory results. Image 1 • A novel method was developed for the sensitive and visual detection of PPD. • DCM as a solid matrix played a vital role in the enrichment of PPD. • The proposed method gave two linear ranges at 0.01–0.1 and 0.1–1 mg L−1, respectively. • The detection limit of PPD was calculated to be 5.35 μg L−1. • Detection mechanism was involved in two-step Schiff base reaction and AIE effect. [ABSTRACT FROM AUTHOR]

• A new fluorescence method was developed for the MPD determination. • The proposed method had a wide linear range of 10–600 μg L−1. • A low detection limit of 4 μg L−1 was obtained. • The method was successfully applied for detecting MPD in real samples. This work presented a new fluorescence method for the determination of m-phenylenediamine (MPD) based on the reaction between MPD and acetylacetone. The formed compound Hacac-MPD exhibited strong blue fluorescence emission under 365 nm excitation. Its fluorescence intensity had an excellent correlation with the MPD concentration Under the optimal conditions, the developed method gave a linear range of 10–600 μg L−1 with a low detection limit of 4 μg L−1. Furthermore, the coexistence of common inorganic ions and other aromatic amines had hardly influence on the determination of MPD, demonstrating high selectivity. Additionally, the MPD in spiked water samples and hair dye samples was successfully detected by the developed method, and the recoveries were 97.5%-101.6% and 98.3%-98.9%, respectively. The established method exhibited a good application prospect for the determination of MPD in environment and daily necessities. [ABSTRACT FROM AUTHOR]

G-protein-signaling modulator 2 (GPSM2) belongs to a protein family that regulates activation of G proteins and plays an important role in mitotic spindle orientation. However, the role of GPSM2 in lung adenocarcinoma (LUAD) is still unclear. In this study, it was found that GPSM2 correlates with clinicopathological features and patient's prognosis in LUAD. Knocking down GPSM2 promoted LUAD cell proliferation in vitro and in vivo. Mechanistically, it was demonstrated that GPSM2 knockdown accelerates cell proliferation via the EGFR pathway. These results confirmed that GPSM2 played an important role in LUAD. Moreover, GPSM2, as an independent prognostic factor, may serve as a potential drug target and prognostic biomarker in LUAD. [ABSTRACT FROM AUTHOR]

• A novel antibacterial membrane containing polyiodides (I-PEI-DCM) was fabricated. • I-PEI-DCM had excellent antibacterial activity against both E. coli and S. aureus. • The iodine loaded on the I-PEI-DCM was the mixture of I 3 − and I 5 −. • The amino groups of PEI participated in the complex reaction with polyiodide ions. • I-PEI-DCM displayed good stability and reusability. Iodine exhibits a broad antibacterial spectrum, low toxicity, high efficiency and no drug resistance. However, free iodine is unstable and has strong irritation on wounds if applied directly. Hence, a carrier improving the stability of iodine is required. In this study, a branched polyethylenimine (PEI) was employed as an iodine carrier. It was firstly fixed to dialdehyde cellulose membrane (DCM) via Schiff-base reaction. Then the PEI-DCM was immersed in an I 2 -KI aqueous solution to prepare a novel antibacterial cellulose membrane containing polyiodides (I-PEI-DCM). Its structure and properties were characterized by SEM, EDX, XPS, Raman, ATR-FTIR, XRD and antibacterial activity. Results demonstrated that the iodine loaded on the I-PEI-DCM was the mixture of I 3 − and I 5 −, whose distribution on the membrane was uniform. During the iodination treatment, the amino groups of PEI molecular chains participated in the complex reaction with polyiodide ions. The microbiological tests showed that the I-PEI-DCM had excellent antibacterial activity against both E. coli and S. aureus. It can completely inactivate all of two bacteria within 0.5 min even after 30-day storage. Meanwhile, the antibacterial membrane exhibited good stability and reusability. Based on the characteristic features, the I-PEI-DCM can be regarded as a promising wound dressing. [ABSTRACT FROM AUTHOR]

[Display omitted] • PEI-functionalized cellulose foam (PEI-CF) with 3D network structure was prepared. • A fluorescence "on–off-on" appeared on the PEI-CF before and after Cr(VI) loaded. • The residual Cr(VI) concentrations in the effluent were below 0.05 mg/L. • Visual recognition of Cr(VI) on the PEI-CF was done in a wide pH range of 2–8. In this work, a novel PEI-functionized cellulose foam (PEI-CF) was prepared by crosslinking polyethyleneimine and cellulose with epichlorohydrin followed freeze drying. The resultant foam not only possessed a three-dimensional network structure but also emitted strong blue fluorescence. It can efficiently remove Cr(VI) from aqueous solution and reduce its concentration below 0.05 mg/L. Other competing anions including NO 3 −, Cl− and H 2 PO 4 − had no remarkable influence on Cr(VI) removal except SO 4 2−. Moreover, the PEI-CF demonstrated good regeneration performance. In addition, a reversible fluorescence "on–off-on" phenomenon was found for the PEI-CF before and after the Cr(VI) loaded under 365 nm UV light. By using the PEI-CF, the visual recognition of Cr(VI) was achieved in a wide pH range of 2–8 and low Cr(VI) concentration of 0.05 mg/L. Coexisting ions (Cu2+, Pb2+, Fe3+, Zn2+, Cr3+, SO 4 2−, Cl−, NO 3 −, H 2 PO 4 − and S2−) had no significant influence on the visual recognition of Cr(VI), exhibiting good selectivity. The PEI-CF showed great promise for the emergency monitoring and Cr(VI) removal in environmental water. [ABSTRACT FROM AUTHOR]