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Graphite is a stack of carbon layers where carbon atoms form hexagons in a honeycomb structure. Graphene on the other hand is a single atom thick layer which offers unique physical, chemical and biological properties compared to graphite. Recycling graphite waste and converting it into graphene or graphène oxide may offer many economic, environmental and health benefits, and may also be used in many applications. Graphite has been used widely in iron-steel, chemical, and nuclear industries for electrical, mechanical and other applications (e.g., metallurgy, pencil, coatings, lubricants and paint), and especially, most of the mold materials of drilling are made of graphite. The major goal of this study is to produce recycled graphène oxide from graphite waste recovered from the drilling mold by using Hummer's method. In this study, graphite-based tailings recovered from drilling mold were collected from local waste collection companies after the sieving and cleaning processes, the resulting graphite is exfoliated in a single layer using a chemical exfoliation process. We herein present a simple, fast, efficient and environmentally friendly technique to prepare graphene oxide (GO) from graphite residues recovered from the drilling mold by using Hummer's method. Complete characterizations of the properties of GO films have been performed. SEM and Raman analyzes showed that the GO sheets prepared in this study had a double-layered and multilamellar structure. X-ray diffraction (XRD) was chosen to measure the crystal structure of our materials. A Fourier transform infrared (FT-IR) spectrum analyzer was used to certify the presence of oxygen-containing functional groups in GO films. The chemical structure of the GO sheet was described in this study. Discussion and references for further research on graphene are provided. [ABSTRACT FROM AUTHOR]

Background: Metformin hydrochloride is a biguanide derivative that has been widely used to treat type 2 diabetes in humans. In veterinary medicine, metformin has shown increasing potential for diabetes treatment in different species, such as equids, dogs, cats and rabbits. It is highly hydrophilic, with incomplete gastrointestinal absorption and very large variability in absolute bioavailability between species, ranging from 4% in equids to 60% in humans. Metformin also shows a short half-life of approximately 2 h in dogs, cats, horses and humans. The objectives of this study were to evaluate a poly (lactic acid) (PLA) metformin microparticle formulation to test in rabbits and conduct a pharmacokinetics study of intravenous (S IV ) and oral solution (S PO ) metformin administration and oral PLA microparticle (S PLA ) administration to rabbits to evaluate the improvement in the metformin pharmacokinetics profile., Results: Metformin-loaded PLA microparticles were characterized by a spherical shape and high encapsulation efficiency. The results from Fourier transform infrared (FTIR) spectroscopy suggested the presence of interactions between metformin and PLA. X-Ray diffraction (XRD) analysis corroborated the results from the differential scanning calorimetry (DSC) studies, showing that metformin is present in an amorphous state within the microparticles. Physicochemical characterization suggested that PLA and metformin hydrochloride interacted within the microparticles via hydrogen bonding interactions. The pharmacokinetic study in rabbits showed sustained-release characteristics from the prepared microparticles with a delay in the time needed to reach the maximum concentration (T max ), decreased C max and bioavailability, and increased mean residence time (MRT) and half-life compared to the pure drug solution., Conclusions: Metformin-loaded PLA microparticles showed optimal and beneficial properties in terms of their physicochemical characteristics, making them suitable for use in an in vivo pharmacokinetic study. The pharmacokinetic parameters of the metformin microparticles from the in vivo study showed a shorter T max , longer MRT and half-life, decreased C max and the prolonged/sustained release expected for metformin. However, the unexpected decrease in bioavailability of metformin from the microparticles with respect to the oral solution should be evaluated for microparticle and dose design in future works, especially before being tested in other animal species in veterinary medicine., (© 2021. The Author(s).)

To determine the effect of in vitro gastrointestinal digestion on the release and antioxidant capacity of encapsulated and nonencapsulated phenolics carob pulp extracts, unripe and ripe carob pulp extracts were microencapsulated with polycaprolactone via double emulsion/solvent evaporation technique. Microcapsules' characterization was performed using scanning electron microscopy and Fourier transform infrared spectrometry analysis. Total phenolics and flavonoids content and antioxidant activities (ORAC, DPPH, and FRAP) were evaluated after each digestion step. The release of phenolic acids and flavonoids was measured along the digestion process by HPLC-MS/MS analysis. The most important phenolics and flavonoids content as well as antioxidant activities were observed after gastric and intestinal phases for nonencapsulated and encapsulated extracts, respectively. The microencapsulation of carob polyphenols showed a protective effect against pH changes and enzymatic activities along digestion, thereby promoting a controlled release and targeted delivery of the encapsulated compound, which contributed to an increase in its bioaccessibility in the gut.