Hollow-fiber liquid-phase microextraction (HF-LPME) and electromembrane extraction (EME) are miniaturized extraction techniques, and have been coupled with various analytical instruments for trace analysis of heavy metals, drugs and other organic compounds, in recent years. HF-LPME and EME provide high selectivity, efficient sample cleanup and enrichment, and reduce the consumption of organic sol-vents to a few micro-liters per sample. HF-LPME and EME are compatible with different analytical in-struments for chromatography, electrophoresis, atomic spectroscopy, mass spectrometry, and electrochemical detection. HF-LPME and EME have gained significant popularity during the recent years. This review focuses on hollow fiber based techniques (especially HF-LPME and EME) of heavy metals and pharmaceuticals (published 2017 to May 2019), and their combinations with atomic spectroscopy, UV-VIS spectrophotometry, high performance liquid chromatography, gas chromatography, capillary elec-trophoresis, and voltammetry.

No abstract available.
Apraxias* ; Ataxia*

In recent times, the emergence of Clostridium perfringens has posed a significant challenge to public health due to its antibiotic resistance and the formation of biofilms. It is the neuraminidase enzyme that supplies toxin secretion from C. perfringens. Since the sialic acid bond is a target recognition point for bacteria, new molecules are needed to treat infections caused by dangerous pathogens such as C. perfringens.The present work focused on an alternative strategy using compounds from Polygonum cuspidatum Sieb. et Zucc. Nine bioactive compounds derived from this plant emodin, physcion, emodin-1-O-β-D-glucopyranoside, emodin-8-O-β-D-glucopyranoside, physcion-8-O-β-D-glucopyranoside, 2-methoxy-6-acetyl-7-methyl juglone, torachrysone-8-O-β-D-glucoside, polydatin and resveratrol were used as ligands and coupled. The neuraminidase enzyme from C. perfringens was chosen as the target protein. The optimal ligand insertion score and ADMET parameters were determined by employing the Lipinski rules as selection criteria. Emodin-8-O-β-D-glucopyranoside and physcion-8-O-β-D-glucopyranoside exhibited drug-like characteristics in their ability to inhibit neuraminidase, as evidenced by a chelation score of −11.9. A comparison was conducted between emodin-8-O-β-D-glucopyranoside and physcion-8-O-β-D-glucopyranoside, and the positive control quercetin.A comprehensive analysis of the drug-like properties of emodin-8-O-β-D-glucopyranoside and physcion-8-O-β-D-glucopyranoside revealed that exhibited superiority over quercetin across multiple aspects. Quercetin showed a binding affinity of −9.9, while emodin-8-O-β-D-glucopyranoside and physcion-8-O-β-D-glucopyranoside showed a binding affinity of −11.9. The results showed acceptable differential kinetic properties of emodin-8-O-β-D-glucopyranoside and physcion-8-O-β-D-glucopyranoside compared to quercetin. It has been shown to inhibit the neuraminidase enzyme from C. perfringens.