Incorporation of CuS nanoparticles into the framework of ZIF-8 provides a chance to integrate near-infrared (NIR) light/low pH triggered release and chemo-photothermal therapy into one system. For the first time, we observed that the framework of ZIF-8 could be disintegrated at pH 7.4 under NIR laser irradiation.

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The quantitative detection methods for many microplastic (MP) polymers in the environment are inadequate. For example, effective detection methods for nylon (polyamide, PA), a widely used plastic, in different environmental samples are still lacking. In the present study, a method based on acid depolymerization−liquid chromatography−tandem mass spectrometry (LC−MS/MS) and without the separation of MPs from samples was developed to quantify nylon MPs. After removing the background monomer compounds, PA6 and PA66 were efficiently depolymerized to 6-aminocaproic acid and adipic acid, respectively, and detected by LC−MS/MS. Accordingly, the quantity of nylon MPs was accurately calculated. By using the proposed method, the recovery of spiked PA6 and PA66 MPs in the environmental samples ranged from 90.8 to 98.8%. The limits of quantification for PA6 and PA66 MPs were 0.680 and 4.62 mg/ kg, respectively. PA MPs were widely detected in indoor dust, sludge, marine sediment, freshwater sediment, fishery sediment, and fish guts and gills with concentrations of 0.725−321 mg/kg. Extremely high concentrations of PA66 MPs were detected in indoor dust and fish guts and gills, indicating the unequivocal risk of human exposure through dust ingestion and dietary exposure.

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Gold- or carbon-based photothermal therapy (PTT) agents have shown encouraging therapeutic effects of PTT in the near-infrared region (NIR) in many preclinical animal experiments. It is expected that gold/carbon hybrid nanomaterial will possess combinational NIR light absorption and can achieve further improvement in photothermal conversion efficiency. In this work, we design and construct a novel PTT agent by coating a carbon nanosphere with patchy gold. To synthesize this composite particle with Janus structure, a new versatile approach based on a facile adsorption-reduction method was presented. Different from the conventional fabrication procedures, the formation of patchy gold in this approach is mainly a thermodynamics-driven spontaneous process. The results show that when compared with the conventional PTT agent gold nanorod the obtained nanocomposites not only have higher photothermal conversion efficiency but also perform more thermally stable. On the basis of these outstanding photothermal effects, the in vitro and in vivo photothermal performances in a MCF-7 cells (human breast adenocarcinoma cell line) and mice were investigated separately. Additionally, to further illustrate the advantage of this asymmetric structure, their potential was explored by selective surface functionalization, taking advantage of the affinity of both patchy gold and carbon domain to different functional molecules. These results suggest that this new hybrid nanomaterial can be used as an effective PTT agent for cancer treatment in the future.

An ionic liquid (IL) based dispersive liquid-liquid microextraction combined with HPLC hydride generation atomic fluorescence spectrometry method for the preconcentration and determination of mercury species in environmental water samples is described. Four mercury species (MeHg(+), EtHg(+), PhHg(+), and Hg(2+)) were complexed with dithionate and the neutral chelates were extracted into IL drops using dispersive liquid-liquid microextraction. Variables affecting the formation and extraction of mercury dithizonates were optimized. The optimum conditions found were as follows: IL-type and amount, 0.05 g of 1-octyl-3-methylimidazolium hexafluorophosphate; dispersive solvents type and amount, 500 μL of acetone; pH, 6; extraction time, 2 min; centrifugation time, 12 min; and no sodium chloride addition. Under the optimized conditions, the detection limits of the analytes were 0.031 μg/L for Hg(2+), 0.016 μg/L for MeHg(+), 0.024 μg/L for EtHg(+), and 0.092 μg/L for PhHg(+), respectively. The repeatability of the method, expressed as RSD, was between 1.4 and 5.2% (n = 10), and the average recoveries for spiked test were 96.9% for Hg(2+), 90.9% for MeHg(+), 90.5% for EtHg(+), 92.3% for PhHg(+), respectively. The developed method was successfully applied for the speciation of mercury in environmental water samples.

Chitosan (CTS) derivative adsorbent [P-C-CTS-(Hg)] was prepared by employing the polyamination and Hg 2+imprinted technologies for Hg 2+ removal from a low-concentration aqueous solution (C Hg 2+ ≤ 40 mg•L −1 ). The prepared adsorbents were characterized by Fourier transform infrared spectroscopy, and their physical and chemical properties were compared. The adsorption capacity of P-C-CTS-(Hg) beads to Hg 2+ was 2.2 times higher than that of CTS beads because of the increased number of amide groups as adsorption sites. The adsorption processes and mechanisms at pH from 1.5 to 5.5 were proposed according to the aqueous mercury species distributions. Langmuir and Freundlich isotherm models were applied to analyze the experimental data of Hg 2+ adsorption by P-C-CTS-(Hg) and predict the relevant isotherm parameters. The best interpretation was given by the Freundlich isotherm equation. The kinetic adsorptions were well described by a pseudo-secondorder reaction model. Furthermore, the results of selectivity adsorption suggested that P-C-CTS-(Hg) possessed good adsorption selectivity for Hg 2+ in the presence of Pb 2+ because of the employment of Hg 2+ -imprinted technology. The regeneration and reutilization of P-C-CTS-(Hg) were investigated. The results showed that the adsorption capacity and adsorption property remained stable after eight reuse cycles.

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