Silica gel impregnated with deep eutectic solvent-based matrix solid-phase dispersion followed by high-performance liquid chromatography for extraction and detection of triazine herbicides in brown sugar.

A novel method was developed to determine six triazine herbicides from brown sugar samples using matrix solid-phase dispersion (MSPD) based on silica gel impregnated with deep eutectic solvent (DES) followed by high-performance liquid chromatography with photodiode array detector (HPLC/PDA). Several factors involved in the MSPD procedure such as DES type, DES content in impregnated silica gel, adsorbent-to-sample mass ratio, type and volume of washing solvent, type and volume of eluent, and grinding time were screened using single-factor experiments and then optimized using Box-Behnken design to accomplish the highest recoveries. The above method demonstrated a good linear range (20-1000 µg kg-1) with a determination coefficient exceeding 0.9962, low limits of determination (1.59-3.77 µg kg-1), acceptable limits of quantifications, and acceptable spiking recoveries (95.0-101.7%) for six triazines under optimized conditions. The proposed MSPD-HPLC/PDA method is a convenient, effective, and sensitive method for rapidly isolating and quantifying six triazines from brown sugar.

Copper-promoted S-arylation reactions with triarylbismuths for the synthesis of diaryl sulfides.

A simple approach for copper-promoted S-arylation reactions utilizing triarylbismuths or triarylantimonys as arylating reagents has been described. These reactions can be performed under mild conditions and exhibit remarkable functional group tolerance and chemoselectivity. The corresponding 2-arylthiopyridine 1-oxide derivatives and arylthioanilines/phenols have been successfully synthesized, achieving good to excellent yields across over 49 examples.

Efficacy of acupuncture for dysphagia after stroke: a systematic review and meta-analysis.

BACKGROUND: The risk of dysphagia after stroke is extremely high. The efficacy of acupuncture in the treatment of dysphagia after stroke lacks high-level evidence-based medical support. This study aimed to systematically evaluate the clinical value of acupuncture therapy in patients with dysphagia after stroke. METHODS: A electronic search of six databases were used to screen for randomized controlled trials (RCTs) of acupuncture treatment of patients with dysphagia after stroke. The search time was from the establishment of the database to 18 October 2020, and the search languages were limited to Chinese and English. The literature was screened and the data extracted independently by two researchers. The Cochrane System Evaluation Manual was used to evaluate the quality of the included literature. RESULTS: A total of 39 RCTs were included, of which 36 studies reported the effective rate of acupuncture treatment for dysphagia. The effective rate of the experimental group was higher than that of the control group [relative risk (RR) =1.23, 95% confidence interval (CI): 1.19 to 1.27, P<0.00001]. The drinking test grading score of patients in the experimental group was lower than that of the control group [mean difference (MD) =-0.75, 95% CI: -1.11 to -0.41, P<0.0001] in 8 studies. The swallowing scores of patients in the experimental group were lower than those in the control group (MD =-4.63, 95% CI: -5.68 to -3.59, P<0.00001) in 8 studies. The Fujishima eating-swallowing rating score of the experimental group was higher than that of the control group [standardized mean difference (SMD) =1.92, 95% CI: 1.30 to 2.54, P<0.00001] in 3 studies. The score of the dysphagia-specific quality of life scale of the experimental group was higher than that of the control group (SMD =2.02, 95% CI: 0.82 to 3.22, P=0.0001) in 5 studies. The VFSS of the experimental group was higher than that of the control group (MD =2.53, 95% CI: 1.89 to 3.17, P<0.00001) in 5 studies. CONCLUSIONS: The existing evidence supports that acupuncture therapy can significantly improve the swallowing function of patients with dysphagia.

A low-cost and effective bagasse-based magnetic porous biochar as an adsorbent for solid phase extraction of triazine herbicides in brown sugar.

A rapid and sensitive approach for enriching and extracting triazines from brown sugar samples was developed by combining magnetic dispersive solid-phase extraction and HPLC/UV. In this work, a magnetic porous biochar (MPB) derived from low-cost bagasse was prepared and successfully employed as an adsorbent. A particular emphasis was placed on optimizing the extraction conditions, including the amount of MPB, extraction time, pH, type and volume of eluent, and salt concentration. Under optimized MSPE conditions, the method showed satisfactory linearity over concentration ranges of 2-200 µg L-1 for four triazines, with correlation coefficient values no less than 0.9981. Low limits of detection (0.27-0.33 µg L-1), good recoveries (81.7-100.7%), and satisfactory repeatability (RSDs ≤ 8.1%) were also demonstrated with respect to the analytical performance. The results demonstrated that the developed method was simple, rapid, sensitive, and efficient, indicating that it could extract and enrich trace triazines from real samples.

Novel Platinum(II) Complex-based Luminescent Probe for Detection of Hypochlorite in Cancer Cells.

Hypochlorite (ClO⁻) is of great importance either for the metabolism of living organisms or as disinfectant in daily life. However, improper concentration levels of ClO⁻ lead to serious health problems including erythrocyte damage, cardiovascular problems, neuron degeneration, lung/kidney injury and cancer. Therefore, a sensitive and selective detection method is required for the visualization and measurement of ClO⁻. In this work, a novel platinum(II) complex-based luminescent probe Pt-CHO was synthesized and utilized to detect ClO⁻. This "turn-off" probe exhibits high sensitivity, excellent selectivity, good pH stability, low limit of detection and instantaneous response ability. Moreover, the luminescent response is caused by the oxidation of aldehyde into carboxyl groups combined with the coordination of hydroxyl groups at the Pt center, which is rarely reported. The cell imaging of HeLa cells proved the considerable potential of the probe for ClO⁻ imaging in living cells.

Development of magnetic porous carbon nano-fibers for application as adsorbents in the enrichment of trace Sudan dyes in foodstuffs.

A novel kind of magnetic porous carbon nano-fibers (Fe3O4@P-CNFs) materials was successfully prepared and used as an adsorbent. Based on the above-mentioned adsorbent, a simple and effective magnetic disperse solid-phase extraction (MSPE) method was developed and first utilized to the enrichment and purification of five Sudan dyes (including Sudan I, Sudan II, Sudan III, Sudan IV, and Sudan Red 7B) in foodstuffs for the first time. High-performance liquid chromatography was used to determine the content of the Sudan dyes. The parameters affecting the extraction performance were studied and optimized, including the amount of the adsorbent and inorganic salt, type and the volume of the eluent, pH of the sample solution and extraction time. Under the optimized experimental conditions, the results show that the proposed method has a good linear relationship (r≥ 0.9993). The limits of detection range from 0.88 µg L-1 to 1.27 µg L-1. The recoveries range from 86.6% to 99.7% with the relative standard deviations ranging from 0.6% to 7.9% in the methodology validation. The above-mentioned results indicate that the proposed method is a sensitive and reliable procedure with good reproducibility for the detection of Sudan dyes residues in foodstuffs.

Hydrazine detection in the gas state and aqueous solution based on the Gabriel mechanism and its imaging in living cells.

A new probe based on the Gabriel mechanism was designed and first used for hydrazine detection with high selectivity against other amines in aqueous solution. Importantly, the probe could be used for gas-state discrimination of hydrazine with different concentrations. Additionally, probe could also be applied for the imaging of hydrazine in living cells.