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An analytical method based on high‐performance liquid chromatography (HPLC) method was developed for the determination of β‐hydroxy‐β‐methylbutyrate (HMB) content in food raw materials. The quantitative detection was performed by HPLC on diode array detector mode under external standard method. The limits of quantification, calculated as 10 times the standard deviation, were 2.0 g/100 g. The average recoveries were in the range of 92.3%–101%, with relative standard deviations below 3.87%, measured at three concentration levels. This method was used to determine the purity of HMB in 10 commercially available food raw materials. The real sample analysis results showed that the content and measurement uncertainties of HMB were 77.1–81.8 g/100 g and 4.51–4.68 g/100 g respectively, which met the requirement of HMB content in the range of 77–82 g/100 g in the HMB announcement. There are no studies on the detection of HMB in food raw materials in the previous reports. The established method provided reference for the rapid quantification and purity analysis of β‐hydroxy‐β‐methylbutyrate in food raw materials. [ABSTRACT FROM AUTHOR]

In this work, we report the synthesis of a new thiosemicarbazone-based drug of N′-(di(pyridin-2-yl)methylene)-4-(thiazol-2-yl)piperazine-1-carbothiohydrazide (HL) featuring a thiazole spectator for efficient coordination with Cu(II) to give [CuCl(L)]2 (1) and [Cu(NO3)(L)]2 (2). Both 1 and 2 exhibit dimeric structures ascribed to the presence of di-2-pyridylketone moieties that demonstrate dual functions of chelation and intermolecular bridging. HL, 1, and 2 are highly toxic against hepatocellular carcinoma cell lines Hep-G2, PLC/PRF/5, and HuH-7 with half maximal inhibitory concentration (IC50) values as low as 3.26 nmol/mL (HL), 2.18 nmol/mL (1), and 2.54 × 10−5 nmol/mL (2) for PLC/PRF/5. While the free ligand HL may elicit its anticancer effect via the sequestration of bio-relevant metal ions (i.e., Fe3+ and Cu2+), 1 and 2 are also capable of generating cytotoxic reactive oxygen species (ROS) to inhibit cancer cell proliferation. Our preliminary pharmacokinetic studies revealed that oral administration (per os, PO) of HL has a significantly longer half-life t1/2 of 21.61 ± 9.4 h, nearly doubled as compared with that of the intravenous (i.v.) administration of 11.88 ± 1.66 h, certifying HL as an effective chemotherapeutic drug via PO administration. [ABSTRACT FROM AUTHOR]

Defects in solution-processed perovskite films can trap photoinduced carriers, facilitate ion migration, and accelerate degradation of perovskites, thus posing a major threat to the performance of perovskite solar cells (PSCs). To address these issues, we rationally proposed a multifunctional sulfonium salt molecule, namely diphenyl-(trifluoromethyl)-sulfonium trifluoromethanesulfonate (TFS-TFMS), which was designed to chelate the detrimental defects of perovskite films using a cost-effective post-treatment method. Theoretical and experimental evidence indicated that defects on the surface and grain boundaries of perovskite films, including uncoordinated Pb2+, volatile organic cations and mobile ionic vacancies, were synergistically anchored by S＝O, –CF3 and TFS+ groups in the TFS-TFMS molecule via Lewis acid–base coordination, hydrogen bonds and electrostatic interactions, respectively. The carrier dynamic behavior and energy level alignment at the interface between perovskites and hole-transportation-layers were also significantly improved. Consequently, the power conversion efficiency (PCE) of PSCs was boosted from 21.99% to 23.56% upon the introduction of TFS-TFMS, along with a diminished hysteresis index. In addition, the TFS-TFMS modified devices without encapsulation can retain 86% and 80% of their initial PCEs under aging conditions of 40–60% relative humidity (1752 h) or heating at 85 °C (504 h), respectively. It is expected that this synergistical design strategy of fluorine-rich sulfonium salt molecules can inspire more potential multifunctional modulators for efficient and stable PSCs towards commercialization in the future. [ABSTRACT FROM AUTHOR]

To understand the role of an additional coordination site in the linker in chirality sensing, we designed and synthesized an S-2-methylbutanamido-substituted m-phthalic diamide-linked zinc bisporphyrinate, [Zn2(S-MAABis)] and investigated its ability to sense the chirality of amino acid esters. The 1H NMR spectra and the crystal structure showed that the amido oxygen adjacent to the chiral carbon was coordinated with zinc. NMR and UV–vis titration showed that the binding of [Zn2(S-MAABis)] to amino acid esters occurred via two equilibria, forming 1:1 and 1:2 host–guest complexes. The CD spectra suggested that [Zn2(S-MAABis)] can effectively recognize the absolute configuration of amino acid esters. The sign of the CD spectra remained unchanged during the titration, indicating that the corresponding 1:1 and 1:2 host–guest complexes had the same chirality. This is different from previously studied amino-substituted m-phthalic diamide-linked zinc bisporphyrinate [Zn2(AmBis)], which showed chirality inversion during titration. Theoretical calculations indicated that the additional coordination sites (amido or amino) in the 1:1 host–guest complexes played different roles, leading to differences in chirality. Our studies suggest that the introduction of a coordination site can influence the chirality transfer process, but the results of chirality transfers are dependent on the specific binding modes. [ABSTRACT FROM AUTHOR]

NiOx as a hole transport material for inverted perovskite solar cells has received great attention owing to its high transparency, low fabrication temperature, and superior stability. However, the mismatched energy levels and possible redox reactions at the NiOx/perovskite interface severely limit the performance of NiOx-based inverted perovskite solar cells. Herein, we introduce a p-type self-assembled monolayer between NiOx and perovskite layers to modify the interface and block the undesirable redox reaction between perovskite and NiOx. The self-assembled monolayer molecules all contain phosphoric acid function groups, which can be anchored onto the NiOx surface and passivate the surface defect. Moreover, the introduction of self-assembled monolayers can regulate the energy level structure of NiOx, reduce the interfacial band energy offset, and hence promote the hole transport from perovskite to NiOx layer. Consequently, the device performance is significantly enhanced in terms of both power conversion efficiency and stability. [ABSTRACT FROM AUTHOR]

Developing clinically meaningful nanomedicines for cancer therapy requires the drugs to be effective, safe, simple, cheap, and easy to store. In the present work, we report that a simple cationic Fe(III)-rich salt of [FeIIICl(TMPPH2)][FeIIICl4]2 (Fe-TMPP) exhibits a superior anticancer performance on a broad spectrum of cancer cell lines, including breast, colorectal cancer, liver, pancreatic, prostate, and gastric cancers, with half maximal inhibitory concentration (IC50) values in the range of 0.098–3.97 μM (0.066–2.68 μg mL−1), comparable to the best-reported medicines. Fe-TMPP can form stand-alone nanoparticles in water without the need for extra surface modification or organic-solvent-assisted antisolvent precipitation. Critically, Fe-TMPP is TME-responsive (TME = tumor microenvironment), and can only elicit its function in the TME with overexpressed H2O2, converting H2O2 to the cytotoxic •OH to oxidize the phospholipid of the cancer cell membrane, causing ferroptosis, a programmed cell death process of cancer cells. [ABSTRACT FROM AUTHOR]