A one-pot synthesis is described to construct a composite of the amino-derivative Zr carboxylate metal–organic framework and silica gel (UiO-66-NH2@silica) as an efficient solid sorbent for hexavalent chromium.

A one-pot synthesis to graft nanocrystallites of the UiO-66-NH 2 MOF on cellulose fibers is described. The grafting process is facilitated by surface functionalization of the cellulose fibers, to express terminal carboxylate groups that act as anchoring sites to coordinate Zr(IV) ions. The stirred reaction mixture ensured rapid nucleation on the porous support surface, and the subsequent homogeneous and complete coverage of the MOF atop the substrate fibers. The method applied to filter membrane demonstrated rapid and effective removal of model contaminants, dichromate ions containing Cr(VI) and methyl orange (MO), (78.2% and 84.5% for Cr(VI) and MO removal, respectively, with in-line filtration setup) from simulated wastewater aqueous solution. This approach delineates an efficient pathway toward grafting the water stable, functional, and microporous Zr-based MOF atop porous support, with potential far reaching applications.

Enzymes play vital roles in diverse industrial sectors and are essential components of many industrial products. Immobilized enzymes possess higher resistance to environmental changes and can be recovered/recycled easily when compared to the free forms. The primary benefit of immobilization is protecting the enzymes from the harsh environmental conditions (e.g., elevated temperatures, extreme pH values, etc.). The immobilized enzymes can be utilized in various large-scale industries, e.g., medical, food, detergent, textile, and pharmaceutical industries, besides being used in water treatment plants. According to the required application, a suitable enzyme immobilization technique and suitable carrier materials are chosen. Enzyme immobilization techniques involve covalent binding, encapsulation, entrapment, adsorption, etc. This review mainly covers enzyme immobilization by various techniques and their usage in different industrial applications starting from 1992 until 2022. It also focuses on the multiscale operation of immobilized enzymes to maximize yields of certain products. Lastly, the severe consequence of the COVID-19 pandemic on global enzyme production is briefly discussed.

The remarkable water stability of Zr-carboxylatebased metal−organic frameworks (MOFs) stimulated considerable interest toward their utilization in aqueous phase applications. The origin of such stability is probed here through pH titration and pK a modeling. A unique feature of the Zr 6 (μ 3 -OH) 4 (μ 3 -O) 4 (RCO 2 ) 12 cluster is the Zr-bridging oxo/hydroxyl groups, demonstrating several pK a values that appear to provide for the water stability at a wide range of pH. Accordingly, the tunability of the cage/surface charge of the MOF can feasibly be controlled through careful adjustment of solution pH. Such high stability, and facile control over cage/surface charge, can additionally be augmented through introducing chemical functionalities lining the cages of the MOF, specifically amine groups in the UiO-66-NH 2 presented herein. The variable protonation states of the Zr cluster and the pendant amino groups, their H-bond donor/acceptor characteristics, and their electrostatic interactions with guest molecules were effectively utilized in controlled experiments to demonstrate high uptake of model guest molecules (137 mg/g for Cr(VI), 1275 mg/g for methylene blue, and 909 mg/g for methyl orange). Additionally, a practical form of the silica-supported MOF, UiO-66-NH 2 @SiO 2 , constructed in under 2 h reaction time, is described, generating a true platform microporous sorbent for practical use in demanding applications.

Children exposed to passive cigarette smoke may develop several structural changes in the respiratory nasal mucosa with subsequent negative effects on its ciliary activity and mucociliary function. As a result of these effects, defense mechanisms of the nose may be ruined or lost, and those children may develop persistent sinonasal infections. Exposure of these children to passive smoking for longer periods of time may also induce other significant changes that were not detected in the present study.

The incidence of traumatic CSF has increased in recent years due to increased incidence of road traffic accidents (RTA) as well the increasing number of endoscopic sinus surgeries (ESS). The objective of this study is to present our experience in management of traumatic CSF leaks using the endoscopic multilayer repair technique. Forty-two patients (aged 10-75 years, 30 males and 12 females) presenting with confirmed post-traumatic CSF rhinorrhea were operated upon between January 2007 and December 2013. The endoscopic multilayer technique was used in all cases. Electromagnetic navigation was used in some cases. All cases presented with intermittent watery rhinorrhea. The duration of the rhinorrhea ranged from 3 days to 1 year before repair. One case presented after 10 years from the causative trauma. Ten cases had a history of meningitis. Nine cases had more than one defect. Iatrogenic defects were larger than defects following accidental trauma. Two cases, following RTA, developed pseudo-aneurysm of internal carotid artery. Ten cases had associated pneumocephalus. The mean duration of postoperative hospitalization was 6 days (range 4-8 days). The mean follow-up duration was 31.2 +/- 11.4 months (range 16-48 months). None of our patient developed serious intra- or postoperative complications. Only one case required another surgery to repair a missed second defect. Post-traumatic CSF leaks can be successfully managed via the endonasal endoscopic route using the multilayer repair technique. It is important to look for multiple defects in these cases. CT angiography is recommended for traumatic leaks involving the lateral wall of the sphenoid sinus to diagnose or exclude the development of pseudo-aneurysm of the internal carotid artery.

Aim: The aim of this study is to compare the phytochemical content and antioxidant potential of Ocimum gratissimum and Telfairia occidentalis leaves. Study Design: This study was made to fit a one-way Analysis of Variance. Place and Duration of Study: This research was carried out in the Department of Premedical Science, Educational Advancement Centre, Ibadan and Pharmaceutical Laboratory of the University of Ibadan, Nigeria between January and June, 2018. Methods: Both plants were purchased from Bodija market in Ibadan, Nigeria. The leaves were removed from the stem and washed with running water to remove contaminants. It was oven dried at 37˚C and milled into powder and extracted with ethanol. The qualitative and quantitative analyses of the phytochemical content as well as antioxidant potential were investigated. Results: The result showed that O. gratissimum is significantly higher in flavonoids content but lower in alkaloids when compared with those of T. occidentalis at P<0.05. No significant difference was observed in the concentrations of saponin, tannin, total phenolics and phytic acid in O. gratissimum when compared with those of T. occidentalis respectively at P<0.05. Antioxidant investigation showed that O. gratissimum is higher in ferric-ion reducing power but lower in ascorbic acid when compared with T. occidentalis respectively at P<0.05. The percentage inhibition of 2,2-diphenyl-1-picryl-hydrazyl-hydrate radical scavenging potential was observed to decrease with decreasing concentration for both plants but that of O. gratissimum was lower when compared with that of T. occidentalis respectively. Conclusion: This pharmacological study is a useful tool for further drug development from the natural plant products.

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