Fluorine-Functionalized Covalent Organic Framework Superhydrophobic Modified Melamine Sponge for Efficient oil-water Separation.

Hydrophobic sponges have attracted significant interest in oil spills and water-oil separation as potential absorption materials due to their desirable absorptivity, selectivity, and elasticity. In this paper, a hydrophilic melamine sponge (MS) is transferred into a superhydrophobic sponge via polydimethylsiloxane (PDMS) modification followed by in situ growth of fluorine-functionalized covalent organic framework (denoted as TFA-COF) nanoparticles. Therefore, the PDMS@TFA-COF@MS sponge was successfully prepared for efficient oil-water separation. The resultant PDMS@TFA-COF@MS exhibits superhydrophobic properties with a water contact angle of 156.7°. The superhydrophobic sponge has selectivity adsorption for different organic solvents and oils from water as well as oil-water separation efficiency (96% after 30 cycles) and oil absorption capacity (12 646% after 30 cycles). Meanwhile, the PDMS@TFA-COF@MS sponge exhibits strong thermal stability and flame retardancy in addition to having exceptional resistance to chemical corrosion in acidic, alkaline, and salt solutions. Moreover, the surfactant-stabilized oil-in-water emulsion could be efficiently separated by the sponge. Therefore, the prepared superhydrophobic PDMS@TFA-COF@MS sponge demonstrates possible uses for long-life oil-water separation applications.

A core-shell structured AuNPs@ZnCo-MOF SERS substrate for sensitive and selective detection of thiram.

Surface-enhanced Raman scattering (SERS) enables pesticide residue monitoring to become facile and efficient. In this study, a core-shell structured gold nanoparticles@ZnCo metal-organic framework (AuNPs@ZnCo-MOF) SERS substrate was designed and successfully synthesized for efficient and selective detection of thiram. The bimetallic ZnCo-MOF shell can not only enrich the targeted molecules in the electromagnetic field because of its excellent absorptive capacity, but also act as a stabilized matrix for protecting the AuNPs from aggregation. The AuNPs@ZnCo-MOFs exhibited a high enhancement factor (EF) of 3.51 × 106 and a low detection limit of 1 × 10-7 mol L-1. Besides, the substrate material showed exceptional stability for up to 28 days at room temperature. The AuNPs@ZnCo-MOFs were used to detect thiram which displayed wide linearity (1 × 10-7 to 1 × 10-4 mol L-1) and high recoveries (83.45-99.61%). Moreover, the AuNPs@ZnCo-MOF SERS substrate exhibited excellent anti-interference ability and size selectivity for the target molecules. These indicate that the AuNPs@ZnCo-MOF substrate has great potential for the detection of thiram residues in practical applications.

Determination of volatile components in cumin by microwave-assisted PDMS/GO/DES headspace solid phase extraction combined with GC-MS.

A novel approach based on polydimethylsiloxane/graphene oxide/deep eutectic solvent (PDMS/GO/DES) sponge headspace solid phase extraction followed by GC-MS was successfully developed to determine the volatile components in cumin. The PDMS/GO/DES exhibits outstanding properties with high adsorption capacity and good chemical stability, and has shown its potentiality as an ideal adsorbent for the extraction of volatile compounds. The influence factors of the extraction process were investigated. Excellent analytical performances were achieved, including wide linearity (0.60-107.72 ng) with high correlation coefficients (R2 ≥ 0.9951), low LODs (0.23-9.23 ng) and LOQs (0.54-18.47 ng), satisfactory precision (intra-day RSDs ≤ 2.85% and inter-day RSDs ≤ 3.92%). Under the optimal extraction conditions, the volatile components in 17 cumin samples from four origins in Xinjiang were analyzed and 31 compounds were identified. PCA was used to establish the relationship between the origins and the volatile compounds for further discriminant analysis. The results showed that the PDMS/GO/DES method was a rapid, simple and sensitive technique for the analysis of volatile components in spices.

Hypoglycemic Bioactivity of Novel Eco-Friendly Carbon Dots Derived from Traditional Chinese Medicine.

Although recent research on intrinsic bioactivities of carbon dots is expanding, it is focused on basic aspects, which creates the need for broadening our knowledge about carbon dots to expand their uses in biomedical sciences and facilitate their application in clinical practice. Jiaosanxian is a charcoal traditional Chinese medicine with a pronounced effect on promoting appetite and digestion that is widely used as dyspepsia therapy in China. To study the underlying mechanism and the material requirements, we investigated carbon dots which was generated in the charcoal processing. In this study, we developed Jiaosanxian-derived carbon dots (JSX-CDs) with an average diameter of 4.4-6.4 nm. No further modifications or external surface passivation agents were required because Jiaosanxian naturally contains carbon, nitrogen, and oxygen. We found that carbon dots derived from different charcoal traditional Chinese medicines had both similarities and differences in their structural features, physicochemical properties, and bioactivities. Due to an abundance of surface groups, JSX-CDs showed a distinct solubility and bioactivity. In this study, we established a modified hyperglycemia model in mice to evaluate the hypoglycemic activity of JSX-CDs. We found that JSX-CDs were effective in regulating blood sugar and appeared to be very safe, indicating its potential use as a hypoglycemic agent. Our results do not only provide guidance for further research on intrinsic bioactivities of CDs but also give new insights into their potential biomedical and healthcare applications.

Novel Carbon Dots Derived from Cirsii Japonici Herba Carbonisata and Their Haemostatic Effect.

The purpose of this study was to explore the haemostatic effect of novel carbon dots (CDs) derived from Cirsii Japonici Herba Carbonisata (CJHC). Transmission electron microscopy (TEM), high-resolution TEM, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, fluorescence spectroscopy, X-ray photoelectron spectroscopy, high performance liquid chromatography and a cell counting kit-8 assay of CJHC-CDs were performed. Then the haemostatic effect of this CJHC-CDs was studied in bleeding mouse models. To explore their related haemostatic mechanism, coagulation parameters and platelets (PLT) were measured. The CJHC-CDs ranged in diameter from 2 to 11 nm and had a quantum yield of 0.63%. They exhibited no toxicity up to concentrations of 5752 µg/mL. After administration, mice had a significantly shortened bleeding time and the coagulation parameters and PLT significantly increased. These results showed the definite haemostatic effect of CJHC-CDs.

The preparation of neem oil microemulsion (Azadirachta indica) and the comparison of acaricidal time between neem oil microemulsion and other formulations in vitro.

The preparation of neem oil microemulsion and its acaricidal activity in vitro was developed in this study. In these systems, the mixture of Tween-80 and the sodium dodecyl benzene sulfonate (SDBS) (4:1, by weight) was used as compound surfactant; the mixture of compound surfactant and hexyl alcohol (4:1, by weight) was used as emulsifier system; the mixture of neem oil, emulsifier system and water (1:3.5:5.5, by weight) was used as neem oil microemulsion. All the mixtures were stired in 800 rpm for 15 min at 40 degrees C. The acaricidal activity was measured by the speed of kill. The whole lethal time value of 10% neem oil microemulsion was 192.50 min against Sarcoptes scabiei var. cuniculi larvae in vitro. The median lethal time value was 81.7463 min with the toxicity regression equations of Y=-6.0269+3.1514X. These results demonstrated that neem oil microemulsion was effective against Sarcoptes scabie var. cuniculi larvae in vitro.