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In addition, we discuss recent developments on the application of nano-spectroscopic characterization for MOF thin-films and explore the potential of MOFs as model systems in catalysis. The conclusions and outlook provide future research possibilities in the field of MOF characterization.The p-aminothiophenol (PATP) coupling reaction on plasmon substrates such as Ag and Au nanoparticles has received extensive attention since the catalytic effect of the surface plasmon was found. Currently, in situ kinetic studies of this reaction are rare, especially those focusing on the specific role of the hot electron-hole carriers. Here, in situ electrochemical surface-enhanced Raman spectroscopy (SERS) is developed to study the plasmon catalytic reaction of PATP in a controlled aqueous environment involving the factors of O2, electron and hole carriers, and solution pH. Ag nanoparticles supported on graphite serve as a SERS substrate, which could separate hot electron-hole pairs effectively and is beneficial to study the effects of hot carriers on plasmon-driven reactions. In situ electrochemical SERS measurements reveal two reaction paths for the PATP coupling reaction. One is that plasmon-induced hot holes activate the dehydrogenation of PATP and then the radical coupling reaction to form p,p'-dimercaptoazobenzene (DMAB) under O2-free conditions. Another is likely to be that the surface Ag2O/AgOH, which is generated from Ag and 1O2/O2-, catalyzes the oxidation of PATP and then the coupling process under O2-rich conditions. Benefitting from the potential/atmosphere controlled measurements in situ, the intermediate species of PATP(NH)/PATP(N) are observed with vibrational bands at around 1056, 1202, 1253, 1395, 1514 and 1540 cm-1.Nanozymes have emerged as enzyme-mimicking nanomaterials to overcome the low stability and high cost of some natural enzymes. The design and fabrication of nanozymes with superior performance to natural enzymes are in urgent demand. Single-atom catalysts offer the unique characteristics of maximum atomic utilization, and are an excellent candidate for nanozymes. However, most of the reported synthesis methods for single-atom catalysts require the preparation of supports for single-atom catalysts in advance, which requires multiple steps and calcination in a high temperature atmosphere. Herein, Cu-N-C single-atom nanozymes (Cu-N-C SAzymes) were successfully designed via a one-pot solvothermal method. Cu-N-C SAzymes exhibited excellent peroxidase-mimicking activity that is superior to some other related nanoparticles. The mechanism study revealed that H2O2 was catalyzed by Cu-N-C SAzymes to generate reactive oxygen species. Furthermore, based on the excellent peroxidase-mimicking activity of the Cu-N-C SAzymes, a simple and sensitive detection method for H2O2 and glucose has been developed.In this article, we report a novel dual on/off thrombin fluorescence aptasensor by combining the energy driven target induced strand displacement reaction and a non-enzyme catalyst recycling DNA machine. Firstly, the specific binding of an aptamer strand and thrombin induce the release of a catalyst which was used as a DNA machine trigger. learn more Subsequently, the catalyst as the trigger initiated the DNA machine through nucleic acid hybridization and branch migration of the DNA machine, resulting in the DNA substrate melting and re-hybridization. In such a working model, the DNA machine achieved cooperative control of the circular strand displacement reaction, realizing catalyst recycling and dual-amplification. The fluorescence signal change of FAM and ROX accumulation had a good linear relationship with the thrombin concentration in the range of 1 fM to 1 nM. On account of catalyst recycling and dual recognition, the detection limit for thrombin was determined to be as low as 0.45 fM (S/N = 3).This biosensor also showed good selectivity for thrombin without being affected by some other proteins, such as PSA, lysozyme etc. Moreover, this assay can be applied to the detection of thrombin in diluted human serum.Injectable, drug-releasing hydrogel scaffolds with multifunctional properties including hemostasis and anti-bacterial activity are essential for successful wound healing; however, designing ideal materials is still challenging. Herein, we demonstrate the fabrication of a biodegradable, temperature-pH dual responsive supramolecular hydrogel (SHG) scaffold based on sodium alginate/poly(N-vinyl caprolactam) (AG/PVCL) through free radical polymerization and the subsequent chemical and ionic cross-linking. A natural therapeutic molecule, tannic acid (TA)-incorporated SHG (AG/PVCL-TA), was also fabricated and its hemostatic and wound healing efficiency were studied. In the AG/PVCL-TA system, TA acts as a therapeutic molecule and also substitutes as an effective gelation binder. Notably, the polyphenol-arm structure and diverse bonding abilities of TA can hold polymer chains through multiple bonding and co-ordinate cross-linking, which were vital in the formation of the mechanically robust AG/PVCL-TA. The SHG formation was successfully balanced by varying the composition of SA, VCL, TA and cross-linkers. The AG/PVCL-TA scaffold was capable of releasing a therapeutic dose of TA in a sustained manner under physiological temperature-pH conditions. AG/PVCL-TA displayed excellent free radical scavenging, anti-inflammatory, anti-bacterial, and cell proliferation activity towards the 3T3 fibroblast cell line. The wound healing performance of AG/PVCL-TA was further confirmed in skin excision wound models, which demonstrated the potential application of AG/PVCL-TA for skin regeneration and rapid wound healing.A sensitive As(iii) ion detection method has been developed based on ion-mediated self-assembly of cysteine (Cys)-capped quantum dots (QDs), and fluorescence self-quenching. A variety of Cys-capped core/shell CdTe/CdS QDs were prepared via hydrothermal methods. Based on the coordination binding between the As(iii) ion and cystine groups anchored on the QDs, addition of As(iii) ions led to self-assembly of the Cys-capped QDs, which was accompanied by fluorescence self-quenching. The fluorescence response was attributed to the exciton energy transfer of the QD aggregates. The ion-mediated fluorescence quenching was further exploited for quantitative determination of As(iii) ions in water. A limit of detection (LOD) of 10 ng L-1 (3σ method) and a linear range from 14 to 70 ng L-1 were obtained for the sensing of As(iii) ions. The system was evaluated using a series of interference targets, and demonstrated high selectivity after addition of mask agents. Finally, the proposed method was successfully employed for the detection of As(iii) in a real water sample.