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Graphical abstract Highlights • Fluorescent sensing of 2,4,6-trinitrophenol by controlling energy transfer between rare earth ions. • Bio-MOF-1 was doped with RE ions to realize ratiometric fluorescent sensing. • Good selectivity, low LOD and linear response were discussed. Abstract 2,4,6-trinitrophenol (PA) is a well-known aromatic compound, due to their higher explosive energy than TNT and their wide utilization when producing organic dyes, medicines and antiseptics. The following paper constructed a composite optical sensing system (denoted as Tb:Eu@MOF) for PA detection using [Zn 8 (ad) 4 (BPDC) 6 O·2 Me 2 NH 2 ]·G, ad = adenine, BPDC = 4,4′-biphenyl dicarboxylic acid, G = DMF and water, as supporting matrix and two rare earth ions, Tb(III) and Eu(III), as dopant. Tb:Eu@MOF was carefully characterized by means of micromorphology, XRD, N 2 adsorption and desorption. Detailed analysis on its photophysical performance indicated weak Tb emission and strong Eu emission, owing to the energy competing between two kinds of rare earth ions in Tb:Eu@MOF. After meeting PA, such energy competing was blocked, leading to enhanced Tb emission and decreased Eu emission. Ratiometric fluorescent sensing for PA detection was thus constructed with good selectivity and low LOD (limit of detection) of 0.87 μM. Linear sensing response was achieved. Its practical sensing application and naked eye detection for PA were tentatively discussed as well. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Size controllable silver nanoparticles were synthesized using HSE as a reductant. • The silver nanoparticles prepared using HSE have an average diameter of 15 nm. • Polyphenol compounds in HSE acts not only as reductant but also as dispersant. • Silver nanoparticles have no cytotoxicity and excellent antimicrobial activities. Abstract Silver nanoparticles have attracted much attention in the medical field in recent years due to their excellent antibacterial properties. In this paper, size controllable silver nanoparticles were synthesized using Hibiscus sabdariffa extract (HSE) as a reductant in 10 min. The silver nanoparticles prepared using HSE as reductant have an average diameter of 15 nm, which is smaller than that of using citric acid as a reductant. Characterization results show that polyphenol compounds in HSE acts not only as reductant but also as dispersant and stabilizer. Moreover, the size of silver nanoparticles is mainly affected by pH value, reaction temperature, and kind of pH regulators. Finally, the silver nanoparticles as antibacterial component was added into cataplasm. The results showed that they have almost no cytotoxicity on 3T3 cells and excellent antimicrobial activities against Gram-positive and Gram-negative bacterium. The above research opens a feasible way for the application of silver nanoparticles in the biomedical field. [ABSTRACT FROM AUTHOR]

Abstract: The selective synthesis of p-cresol by gas-phase alkylation of phenol with methanol was studied on SiO2–Al2O3 and zeolites HBEA, HZSM5 and HMCM22. Cresols were formed from phenol alkylation of methanol via two parallel pathways: the direct C-alkylation of phenol and the conversion of anisole intermediate obtained by O-alkylation of phenol. Methylation of o- and p-cresol led to the formation of 2,6- and 2,4-xylenols while anisole produced methylanisoles either by alkylation with methanol or by disproportionation. Regarding the cresol isomers distribution, p- and o-cresol were the major products on all the samples while m-cresol formation remained always lower than 6%. SiO2–Al2O3, HBEA and HZSM5 exhibited similar initial p-cresol:o-cresol ratios, between 0.6 and 0.8. In contrast, p-cresol was the predominant product on HMCM22 because the narrow sinusoidal 10-membered ring channels of this zeolite were particularly suitable for improving by shape selectivity the formation of p-cresol. Thus, we report here that p-cresol yields of 55% and p-cresol:o-cresol ratios of 4 are obtained on HMCM22 by gas-phase alkylation of phenol with methanol at 473K, atmospheric pressure and contact time of 350gh/mol phenol. [Copyright &y& Elsevier]

Аbstract This paper describes Quantitative Structure-Activity Relationships (QSAR) studies, molecular docking and in vitro antibacterial activity of several potent imidazolium-based ionic liquids (ILs) against S. aureus ATCC 25923 and its clinical isolate. Small set of 131 ILs was collected from the literature and uploaded in the OCHEM database. QSAR methodologies used Associative Neural Networks and Random Forests (WEKA-RF) methods. The predictive ability of the models was tested through cross-validation, giving cross-validated coefficients q 2  = 0.82–0.87 for regression models and overall prediction accuracies of 80–82.1% for classification models. The proposed QSAR models are freely available online on OCHEM server at https://ochem.eu/article/107364 and can be used for estimation of antibacterial activity of new imidazolium-based ILs. A series of synthesized 1,3-dialkylimidazolium ILs with predicted activity were evaluated in vitro . The high activity of 7 ILs against S. aureus strain and its clinical isolate was measured and thereafter analyzed by the molecular docking to prokaryotic homologue of a eukaryotic tubulin FtsZ. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO), as a material with attractive properties, has attracted great interest worldwide, particularly owing to the implementation of the synthesis of nano-sized particles. High luminescent efficiency, a wide band gap (3.36 eV), and a large exciton binding energy (60 meV) has triggered intense research on the production of nanoparticles using different synthesis methods and on their future applications. ZnO nanomaterials can be used in industry as nano-optical and nano-electrical devices, in food packaging and in medicine as antimicrobial and antitumor agents. The increasing focus on nano zinc oxide resulted in the invention and development of methods of nanoparticles synthesis. Recently, various approaches including physical, chemical and biological (“ green chemistry ”) have been used to prepare ZnO nanocomposites with different morphologies. The obtained nanoparticles can be characterized with a broad range of analytical methods including dynamic light scattering (DLS), electron microscopy (TEM, SEM), UV–VIS spectroscopy, X-ray diffraction (XRD) or inductively coupled plasma with mass spectrometry (ICP-MS). With these it is possible to obtain information concerning the size, shape and optical properties of nanoparticles. ZnO NPs exhibit attractive antimicrobial properties against bacteria (Gram-positive and Gram-negative) and fungi. Zinc oxide nanocomposites show also selective toxicity toward normal and cancerous cells, which is explained by reactive oxygen formation (ROS). Yet despite the potentially interesting antitumor activity of ZnO nanoparticles, it has been proven that they can be also cytotoxic and genotoxic for multiple types of human cells (i.e. neuronal or epithelial cells). This paper reviews the methods of synthesizing zinc oxide nanocomposites as well as their characteristics, antimicrobial activity and cytotoxicity against normal and tumor cells. [ABSTRACT FROM AUTHOR]

Abstract: Silver sulfadiazine (AgSD) is a topical antibiotic with limited aqueous solubility. In this study, it was shown that poly(amido amine) (PAMAM) dendrimer complexes with SD (SDZ) and silver (Ag) could be used for a bottom-up approach to synthesize highly-soluble AgSD nanoparticles (NPs). These NPs were stabilized against crystal growth by electrostatic layer-by-layer (LBL) coating with various PAMAM dendrimers. Additionally, AgNPs can be incorporated in the dendrimer shells that augmented AgSD release. NP formulation in a cream base provided a topical drug-delivery platform with enhanced antibacterial properties against burn-wound infections, comprising three nanostructures i.e., nano-AgSD, AgNPs as well as PAMAM dendrimers, in one efficient, elegant nanosystem. From the Clinical Editor: In this paper an elegant silver sulfadiazine-based nanoparticle complex is demonstrated with enhanced antibacterial properties and improved solubility for the treatment of burn-wound infections in a topical crème formulation. [Copyright &y& Elsevier]

Abstract: Pollution mitigation is an important target for restored wetlands, and although there is much information in relation to nutrient removal, little attention has been paid to emerging contaminants. This paper reports on the occurrence and attenuation capacity of 17 emerging contaminants in a restored wetland and two rivers in North-East Denmark. The compounds belong to the groups of pharmaceuticals, fragrances, antiseptics, fire retardants, pesticides, and plasticizers. Concentrations in surface waters ranged from 2 to 1476ngL−1. The compounds with the highest concentrations were diclofenac, 2-methyl-4-chlorophenoxyacetic acid (MCPA), caffeine, and tris(2-chloroethyl) phosphate (TCEP). The herbicide concentrations increased after a rain-fall event, demonstrating the agricultural run-off origin of these compounds, whereas the concentration of the other emerging contaminants was rather conservative. The mitigation capacity of the restored wetland for the compounds ranged from no attenuation to 84% attenuation (19% on average). Hence, restored wetlands may be considered as a feasible alternative for mitigating emerging contaminants from river waters. [Copyright &y& Elsevier]

Abstract: AdaBoost Learner is employed to investigate Structure–Activity Relationships of phenols based on molecular descriptors. In this paper, the performance of AdaBoost Learner is compared with support vector machine (SVM), artificial neural networks (ANNs) and K nearest neighbors (KNNs), which are the most common algorithms used for SARs analysis. AdaBoost Learner performed better than SVM, ANNs and KNNs in predicting the mechanism of toxicity of phenols based on molecular descriptors. It can be concluded that AdaBoost has a potential to improve the performance of SARs analysis. We believe that AdaBoost Learner will play an important and complementary role to the existing algorithms for the prediction of the mechanisms of toxicity based on SARs. We have developed an online web server for the prediction of ecotoxicity mechanisms of phenols, accessible at http://chemdata.shu.edu.cn/ecotoxity/. [Copyright &y& Elsevier]

Abstract: The face is the central point of the physical features of the human being. It transmits expressions and emotions, communicates feelings and allows for individual identity. It contains complex musculature and a pliable and unique skin envelope that reacts to the environment through a vast network of nerve endings. The face hosts vital areas that make phonation, feeding, and vision possible. Facial burns disrupt these anatomical and functional structures creating pain, deformity, swelling, and contractures that may lead to lasting physical and psychological sequelae. The management of facial burns may include operative and non-operative treatment or both, depending on the depth and extent of the burn. This paper intends to provide a review of the available options for topical management of facial burns. Topical agents will be defined as any agent applied to the surface of the skin that alters the outcome of the facial burn. Therefore, the classic concept of topical therapy will be expanded and developed within two major stages: acute and rehabilitation. Comparison of the effectiveness of the different treatments and relevant literature will be discussed. [Copyright &y& Elsevier]

Abstract: Cytisine has a molecular structure somewhat similar to that of nicotine and varenicline. The concept for the new smoking cessation drug varenicline was based partly on cytisine. Like varenicline, cytisine is a partial agonist of nicotinic acetylcholine receptors, with high affinity for α4β2 receptors. Cytisine has been used since the 1960s as a smoking cessation drug in Eastern and Central Europe, but has remained largely unnoticed elsewhere. Three placebo-controlled trials, conducted in East and West Germany in the 1960s and 1970s, suggest that cytisine, even with minimal behavioural support, may be effective in aiding smoking cessation. Cytisine tablets are very inexpensive to produce and could be a more affordable treatment than nicotine replacement, bupropion and varenicline. There is however a dearth of scientific research on the properties of cytisine, including safety, abuse liability and efficacy. This paper seeks to identify research priorities for molecular, animal and clinical studies. In particular, new studies are necessary to define the nicotinic receptor interaction profile of cytisine, to establish its pharmacokinetics and pharmacodynamics in humans, to determine whether animals self-administer cytisine, and to ascertain whether cytisine is safe and effective as a smoking cessation drug. Potentially, this research effort, contributing to wider use of an inexpensive drug, could save many lives. [Copyright &y& Elsevier]

Abstract: The paper describes the use of micro thermal analyzer (μTA) for assessment of compatibilization in blends of nitrile rubber (NBR) with neat high-density polyethylene (HDPE), phenolic resin modified together with dynamically vulcanized HDPE and polyvinyl chloride (PVC). Micro thermal analyzer (μTA) was employed to identify different locations by the study of thermal conductivity of the surface and topographic features. Local thermal analysis (LTA), e.g., micro thermomechanical analysis (μTMA) and micro differential thermal analysis (μDTA), were conducted at these locations. Blending of NBR with unmodified HDPE shows incompatibility. Modification of HDPE by phenolic resin and dynamic cross-linking by peroxide resulted in technological compatibilization of the blend, while NBR and PVC generated characteristics of a miscible blend. [Copyright &y& Elsevier]

Abstract: This paper presents the development and application of a solid phase microextraction method for the full investigation of chlorhexidine interaction with saliva during a pharmacokinetic study: chemical stability, binding to proteins, free concentration, total concentration and kinetics of elimination after oral administration. Only 0.1mL sample were needed for each time point and the concentration of salivary proteins was determined as well. It was shown that chlorhexidine remained stable in the oral cavity for at least 9h and high concentrations of the drug (2μg/mL total) were still present even 8h after mouthrinsing. Supplementary facts were uncovered: while the total concentration followed first-order elimination kinetics, the free concentration remained almost constant for several hours; this showed that the oral cavity acted like a reservoir that slowly released the drug. It was also revealed that following oral administration of chlorhexidine, the normal composition of saliva changed for a few hours, probably as a physiological response to the bitter taste of the medicine. The method had a wide linear range (0.1–40μg/mL free chlorhexidine) that was perfectly suitable for the study of chlorhexidine retention in the oral cavity. Separation and quantitation were achieved by liquid chromatography coupled to mass spectrometry; no interference from endogenous compounds was observed. This selective and sensitive solid-phase microextraction (SPME) approach for monitoring the free and total concentration of a drug, as well as the concentration of proteins that bind that drug, should prove to be more useful for pharmacokinetic studies than classic methods that only provide the total concentration as a final result. [Copyright &y& Elsevier]

Ultrasound alone is capable of killing bacteria when sufficient power is applied but ultrasound at low powers can also be used to improve the effectiveness biocides. In this paper, we explore the effect of the timing of the ultrasonic treatment at 20 and 850 kHz on the biocidal efficiency of sodium hypochlorite solution towards Escherchia coli suspensions. A remarkable frequency effect has been noted. At the lower frequency of 20 kHz the improvement in biocidal activity is greatest when the ultrasound is applied at the same time as the hypochlorite. At the higher frequency of 850 kHz the improvement is best when ultrasound is used as a pre-treatment immediately followed by hypochlorite addition under normal (silent) conditions. The kill rate achieved for pre-treatment using 850 kHz and simultaneous treatment using 20 kHz are very similar. However the former involves less acoustic energy and so is considered to be the more efficient. [Copyright &y& Elsevier]

• Key challenges in antisepsis include wound healing and skin tolerability • Antimicrobial resistance is also an increasing challenge in antisepsis • Povidone-iodine has the broadest spectrum of activity versus other antiseptics • Povidone-iodine has acceptable tolerability and no reports of resistance • Povidone-iodine promotes wound healing and is effective against bacterial biofilms Objectives: Using antiseptics in wound care can promote healing by preventing and treating infection. However, using antiseptics can present many challenges, including issues with tolerability, inactivation by organic matter and the emergence of antimicrobial resistance/cross-resistance. This review discussed the key challenges in antisepsis, focusing on povidone-iodine (PVP-I) antiseptic. Methods: Literature searches were conducted in PubMed, in January 2019, with a filter for the previous 5 years. Searches were based on the antimicrobial efficacy, antiseptic resistance, wound healing properties, and skin tolerability for the commonly used antiseptics PVP-I, chlorhexidine gluconate (CHG), polyhexanide (PHMB), and octenidine (OCT). Additional papers were identified based on author expertise. Results: When compared with CHG, PHMB and OCT, PVP-I had a broader spectrum of antimicrobial activity against Gram-negative bacteria, actinobacteria, bacterial spores, fungi and viruses, and a similar and broad spectrum of activity against Gram-positive bacteria. PVP-I was also highly effective at eradicating bacterial biofilms, which is a vitally important consideration for wound care and infection control. Despite a long history of extensive use, no resistance or cross-resistance to PVP-I has been recorded, which is in contrast with other antiseptics. Despite previous misconceptions, it has been shown that PVP-I has low allergenic properties, low cytotoxicity and can promote wound healing through increased expression of transforming growth factor beta. Conclusion: With increased understanding of the importance of tackling antimicrobial resistance and bacterial biofilms in acute and chronic wound care, alongside improved understanding of the challenges of antiseptic use, PVP-I remains a promising agent for the management of antisepsis. [ABSTRACT FROM AUTHOR]

The use of Alcohol-based antiseptics is efficient and approved, however it has some limitations. This paper examined the possibility of using hypochlorite water as a chlorine-based antiseptic for handwashing in public buildings and healthcare facilities. The electrolysis method was used, which produces Hypochlorous acid (HOCl) from mixing drinking water with small amounts of sodium hydroxide. Hypochlorous acid is usually produced by blood cells to surround pathogens when the skin is cut and exposed to pathogens. The methods used were based on hydrolysing drinking water at a different salt concentration (from 0 up to saline water 0.9% NaCl) under the different power supply. The results showed that 0.005–0.01% hydrochloride water can be a perfect antiseptic that can kill most bacteria and pathogenies within 12 s. In one prototype set up one litter of the prepared solution needed the only 2 g of NaCl, 12 V and 3 amps' power. However, the pH value should be maintained to be around 5–6. The results also showed that the most efficient way was to produce the solution on-site. However, if stored properly it can be used for 7–10 days after production. Unlabelled Image • Electrolysis was used to produce hypochlorite water from saline water. • Alcohol-based antiseptics are effective against pathogens, but it has limitations. • HOCl is produced by leucocytes when skin is cut and exposed to pathogens. • Care should be taken in producing chlorine-based antiseptics. [ABSTRACT FROM AUTHOR]

An abstract of the paper " Effects of ultraviolet light irradiation on hatchability of floor eggs from White Leghorns," by C. Coufal and colleagues is presented.