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Humidity-temperature dual-functional sensors show great demand in healthcare and archaeology, requiring sensors with high sensitivity, high resolution and high stability. In this work, utilizing the post-coordination strategy, the uncoordinated N atoms in MOF-303 were used as the metal chelate sites to chelate CuCl 2 , and due to the accordion-like morphology, the obtained material shows potential in humidity sensing and temperature sensing. The CuCl 2 -MOF-303 based sensor shows whole range humidity sensing with response of 11.4 at 33 % RH and 56,700 at 95 % RH, 1 % RH of resolution and good long-term stability (>90 days), and excellent temperature sensing performance of high sensitivity (–3.3 %/°C), high linearity (R2>0.99) and high resolution (0.3 °C) in the temperature range of 35–38 °C. Furthermore, the application of sensor in healthcare, noncontact sensing and information transmission is verified. This study provides a preliminary exploration for the application of MOFs in humidity-temperature dual-functional sensors. • Cu(II) coordination MOF-303 was prepared through post-coordination strategy. • CuCl 2 -MOF-303 based sensor shows highly sensitive to humidity and temperature with high response and resolution. • The sensing mechanism is discussed from aspects of contact, interaction and signal transformation process. • The sensor was proved to have applications in healthcare, noncontact sensing and information transmission. [ABSTRACT FROM AUTHOR]

Highlights • Complex 1 is the first long-lived probe to detect IO 4 − in living cells. • Complex 1 has a detection limit of 0.077 μM for IO4− in aqueous buffer, more sensitive than reported fluorescence probes. • The long lifetime of Complex 1 enables its luminescence response to IO4− to be detected in the presence of organic dyes. Abstract Periodate (IO 4 −) is a widely used reagent in organic synthesis and for biomolecular modification. However, highly sensitive fluorescence detection methods for IO 4 − are lacking. In this work, we designed and synthesized iridium(III) complexes for the detection of IO 4 − by the incorporation of a methylthio group to serve as a luminescence trigger. The results showed that complex 1 could detect IO 4 − in a sensitive and selective manner with a detection limit of 0.077 μM, rendering it more sensitive than reported fluorescence methods. Meanwhile, its inherently long emission lifetime enables its luminescence response to IO 4 − to be detected even in the presence of organic dyes by the use of time-resolved emission spectroscopy (TRES). This probe was further demonstrated to detect IO 4 − in living cells. To our knowledge, complex 1 is first long-lived iridium(III)-based probe for the sensitive detection of IO 4 −, and is also one of few existing imaging probes for IO 4 −. [ABSTRACT FROM AUTHOR]

Graphical abstract A pH and thermal stable 3D framework [Mg(ATDC)(H 2 O) 2 ] n (1) as fluorescence sensor with accessible -NH 2 has been successfully synthesized and characterized. It is the first reported highly selective bi-responsive fluorescence Mg-MOF for sensing 2,4,6-Trinitrotoluene(TNT), and have the highest sensitivity for detecting Chromium(III) simultaneously through fluorescence quenching. The quenching mechanisms are mainly attributed to the photo-induced electron transfer and competitive absorptions between the excitation/emission of Mg-MOF and analytes, rather than the interactions between –NH 2 and analytes. Highlights • A new luminescence Mg-MOF was synthesized, the structure was analyzed in detail. • Fluorescent sensing experiment exhibits complex 1 has high sensitivity for 2,4,6-Trinitrotoluene (TNT). • Fluorescent sensing experiment also exhibits complex 1 has high selectivity for Cr3+ ion. • The detection mechanisms and recyclability were studied based on both experiments and calculation. Abstract A pH and thermal stable three dimensional framework [Mg(ATDC)(H 2 O) 2 ] n (1) (H 2 ATDC = 2′-amino-1,1′:4′,1′'-terphenyl-4,4′'-dicarboxylate) with blue fluorescence has been successfully synthesized and characterized. The Mg-MOF contains 2D [Mg(COO) 2 ] n sheet, which links ATDC2− to generate 3D framework with accessible -NH 2 groups, which could be beneficial to impact the reorganization on specific small molecules. Importantly, it is the first reported highly selective fluorescence Mg-MOF for sensing 2,4,6-Trinitrotoluene (TNT), and have the highest sensitivity for detecting Chromium(III) simultaneously through fluorescence quenching. Furthermore, the quenching mechanisms are mainly attributed to the photo-induced electron transfer and competitive absorptions between the excitation/emission of Mg-MOF and analytes, rather than the interactions between –NH 2 and analytes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Humidity sensors based on glycidyl trimethyl ammonium chloride (EPTAC) modified cellulose paper via a facile solution method were fabricated. • The paper is used for the purpose of the humidity sensing material and the sensor substrate. • The as-fabricated paper-based humidity sensor is provided with outstanding humidity sensing properties and good stability. • The humidity sensor was applied to multifunctional applications including human breath rate, non-contact switch and skin humidity. It is of great significance to exploit a simple, cost-effective and environmentally friendly preparation method of multifunctional humidity sensors. However, most humidity sensors need complex manufacturing processes, high cost and narrow usage range. Herein, humidity sensors based on glycidyl trimethyl ammonium chloride (EPTAC) modified cellulose paper via a facile solution method were fabricated, among which the paper is used for the purpose of the humidity sensing material and the sensor substrate. The sensitivity of the obtained sensor was improved by the modification of EPTAC, the response time was decreased to 25 s, which is equivalent to the first-rate paper-based humidity sensors. In addition, the paper-based humidity sensor is provided with well flexibility and biocompatibility, and it exhibits multifunctional applications in respiratory monitoring, non-contact switch and skin humidity monitoring. The low cost and facile preparation technique in this work could provide a useful strategy for developing multifunctional humidity sensor. [ABSTRACT FROM AUTHOR]