Metal organic frameworks (MOFs) are promising materials for the controlled release of drugs. Molecular docking methods have been successfully applied to the fast screening of lead compounds starting from the threedimensional structure of proteins. We apply molecular docking calculations to MOFs as a fast approach to distinguish between good and poor drug candidates for incorporation. The approach can predict the binding behavior of different guest molecules in agreement to experimental measurements using X-ray powder diffraction, thermogravimetry-differential thermal analysis, and UV-vis spectroscopy techniques. It can also identify the overall binding mode of tested compounds and estimate binding affinity differences above the error of 2 kcal mol À1 or 8.4 kJ mol À1 associated with the empirical scoring function used in the calculations. This exploratory investigation indicates that the molecular docking technique may be useful in the fast screening of drug candidates for adsorption to coordination polymers for controlled drug delivery and/or environmental remediation.

Two novel coordination polymers (CPs) have been synthesized, characterized and successfully applied as robust heterogeneous catalysts for the Biginelli multicomponent reaction to obtain 3,4dihydropyrimidin-2(1H)-one or thione (DHPMs) derivatives. The reaction was initially developed using both CPs and the Zn-based material showed much better catalytic activity. After the reaction optimization under batch conditions, a continuous flow protocol was developed and applied with impressive results. Four bioactive DHPMs were successfully synthesized with high yields. The mechanism of the transformation was also investigated by electrospray (tandem) mass spectrometry (ESI-MS(/MS)) analyses. Online monitoring of the reaction indicated under the developed conditions that the iminium mechanism is preferred over the enamine-and Knoevenagel-based mechanisms. Nine DHPMs had their antitumoral activities evaluated against MCF-7 (human breast cancer cells), A549 (human alveolar basal epithelial cells) and Caco-2 (human epithelial colorectal cells) cancer cell lineages. Fibroblasts (healthy cells) were not affected by the tested DHPMs showing an excellent selectivity for tumour cells. Three DHPMs returned impressive results, being capable of inhibiting tumour cell proliferation in 72 h.

The coordination polymer [Zn(BDC)(H(2)O)(2)](n) was tested for extraction of pyrimethanil, ametryn, dichlofluanid, tetraconazole, flumetralin, kresoxim-methyl and tebuconazole from the medicinal plant Hyptis pectinata, with analysis using gas chromatography-mass spectrometry in selected ion monitoring mode (GC/MS, SIM). Experiments carried out at different fortification levels (0.1, 0.5 and 1.0 μg g(-1)) resulted in recoveries in the range 73-97%, and RSD values were between 5 and 12% for the [Zn(BDC)(H(2)O)(2)](n) sorbent. Detection and quantification limits ranged from 0.02 to 0.07 μg g(-1) and from 0.05 to 0.1 μg g(-1), respectively, for the different pesticides studied. The method developed was linear over the range tested (0.04-14.0 μg g(-1)), with correlation coefficients ranging from 0.9987 to 0.9998. Comparison between [Zn(BDC)(H(2)O)(2)](n) and the commercial phase C(18)-bonded silica showed good performance of the [Zn(BDC)(H(2)O)(2)](n) polymeric sorbent for the pesticides tested.

This manuscript reports the first example of up-conversion properties involving Yb 3+ and Tb 3+ ions in five isostructural Lanthanide-Organic Frameworks (LnOFs), herein designated as UCMarker-1 to UCMarker-5, respectively, and their application as optical probes for the identification of gunshot residues (GSRs) and the ammunition encryption procedure. The excitation of the Yb 3+ 2 F 7/2 « 2 F 5/2 transition (980 nm) at room temperature leads to visible up-conversion (UC) emission of Tb 3+ 5 D 4 A 7 F J . The GSR and lead-free primer residues are easily identified upon UV radiation (l = 254 nm). These results prove that the exploration of LnOFs to identify GSR is attractive for the identification of ammunition origins or caliber recognition.

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In this work, the grapheme oxide (GO) and GO/ZnO nanocomposite were successfully obtained from the oxidation of graphite and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). In the GO/ZnO nanocomposite, the GO sheets were coated with aggregated ZnO nanoneedles with ca. 20 nm of diameter. The obtained materials were used as heterogeneous catalysts for acetylation of Soybean Fatty Acids Methyl Esters (FAME), promoting the epoxy ring-opening using acetic anhydride. The epoxy ring was almost completely opened in the presence of GO or GO/ZnO nanocomposites, with conversion rates up to 99% and selectivity of ca. 90%, and partially opened using only ZnO. The GO/Zn and GO catalysts were reused three times with conversion rates of ca. 85 and 74%, respectively.

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The accumulation of antibiotics in wastewater has led to the development and spreading of antibiotic resistance in the environment. Amoxicillin (Amox), a beta-lactamic antibiotic, is one of the most frequently consumed antibiotics in the world. We have applied two metal-organic frameworks (MOFs) containing zinc(II) as platforms to degrade Amox. We have predicted the adsorption of this antibiotic via molecular docking calculations which have been further corroborated by means of Fourier transform infrared and UV-Vis spectroscopies, thermogravimetric analysis, X-ray diffraction and scanning microscopy measurements. We have subsequently performed mass spectrometry analysis of Amox@zeolitic imidazolate framework-8 (ZIF-8) and Amox@Zn(1,4-benzenedicarboxylate) (ZnBDC) to demonstrate the degradation of Amox upon contact with the Zn-containing frameworks. We propose a possible pathway for the degradation of Amox involving the cleavage of the four-membered β-lactam ring. These Zn-containing frameworks provide a biocompatible platform for the degradation in solution of Amox, which should also be suitable to degrade other β-lactam antibiotics.Keywords: β-lactamase activity, gentamicin, β-lactam catalysis, penicilloic and penilloic acids, biocompatible frameworks IntroductionIn the last decade, antibiotics have emerged as novel environmental pollutants. The widespread use of antibiotics in human and veterinary medicine, animal husbandry, plant production and aquaculture has led to high consumption and the gradual accumulation of antibiotics in the environment (e.g., wastewater, landfills, industrial and hospital effluents). [1][2][3][4][5][6] From 100,000 to 200,000 t of antibiotics are consumed per year in hospitals, homes, veterinary use and aquaculture throughout the world. On average, high-income countries generate ca. 0.5 kg of hazardous waste per bed per day whereas low-income countries generate ca. 0.2 kg. Furthermore, low-income countries do not separate hospital waste into hazardous or non-hazardous wastes, making the real quantity of hazardous waste much higher, as reported by the World Health Organization (WHO).Environmental accumulation of antibiotics has raised serious concerns about the induction of antibiotic resistance. [8][9][10] The exposure of bacteria to the subinhibitory antibiotic concentrations found in many natural environments such as sewage water and sludge, rivers, lakes and even drinking water is a crucial aspect of the current antibiotic resistance crisis.11-14 Furthermore, the incomplete absorption or metabolism of antibiotics in target organisms may lead to excretion rates from 5 to 90% of the dose in the form of metabolites or as parent compounds. 15,16 The chemical structure of antibiotics often contains cyclic moieties such as benzene rings, piperazine units, hexahydropyrimidines, sulfonamides, quinolone, and morpholine groups.5 Upon metabolic processing in humans and animals, these meta-stable compounds yield activated metabolites, which are continuously released in Metal Organic Framewor...