Drug delivery constitutes the formulations, technologies, and systems for the transport of pharmaceutical compounds to specific areas in the body to exert safe therapeutic effects. The main criteria for selecting the correct medium for drug delivery are the quantity of the drug being carried and the amount of time required to release the drug. Hence, this research aimed to improve the aforementioned criteria by synthesizing a medium based on calcium carbonate-nanocellulose composite and evaluating its efficiency as a medium for drug delivery. Specifically, the efficiency was assessed in terms of the rates of uptake and release of 5-fluorouracil. Through the evaluation of the morphological and chemical properties of the synthesized composite, the established 3D printing profiles of nanocellulose and CaCO3 took place following the layer-by-layer films. The 3D printed double laminated CaCO3-nanocellulose managed to release the 5-fluorouracil as an effective single composition and in a time-controlled manner. � 2020 by the authors.

Tannin was successfully extracted from Gelam bark using acetone as the solvent as natural alternatives. The extracted tannin was then used as corrosion inhibitor for mild steel under acidic medium. The gravimetric and electrochemical potentiodynamic corrosion tests were executed at different purified and unpurified tannin concentrations (200-800 ppm) to test the ability to inhibit mild steel corrosion. The results showed that the corrosion rate decreased as tannin concentration increased while the inhibition efficiency increased. The isotherm adsorption found that the Langmuir model was the best model to represent the interaction of tannin inhibitor and the active sites on mild steel surface. The SEM analysis showed that the mild steel morphology changed after the addition of tannin. The presence of blue-black color on the mild steel surface indicated the formation of ferric tannate to protect the surface of mild steel. In conclusion, purified tannin was a better inhibitor compared to unpurified tannin on mild steel in 1 M HCl. � 2018, Malaysian Society of Analytical Sciences. All rights reserved.

In this study, lignin has been extracted from oil palm empty fruit bunch (EFB) fibers via an organosolv process. The organosolv lignin obtained was defined by the presence of hydroxyl-containing molecules, such as guaiacyl and syringyl, and by the presence of phenolic molecules in lignin. Subsequently, the extracted organosolv lignin and graphene nanoplatelets (GNP) were utilized as filler and reinforcement in photo-curable polyurethane (PU), which is used in stereolithography 3D printing. The compatibility as well as the characteristic and structural changes of the composite were identified through the mechanical properties of the 3D-printed composites. Furthermore, the tensile strength of the composited lignin and graphene shows significant improvement as high as 27%. The hardness of the photo-curable PU composites measured by nanoindentation exhibited an enormous improvement for 0.6% of lignin-graphene at 92.49 MPa with 238% increment when compared with unmodified PU. � 2019 by the authors.

The materials for additive manufacturing (AM) technology have grown substantially over the last few years to fulfill industrial needs. Despite that, the use of bio-based composites for improved mechanical properties and biodegradation is still not fully explored. This limits the universal expansion of AM-fabricated products due to the incompatibility of the products made from petroleum-derived resources. The development of naturally-derived polymers for AM materials is promising with the increasing number of studies in recent years owing to their biodegradation and biocompatibility. Cellulose is the most abundant biopolymer that possesses many favorable properties to be incorporated into AM materials, which have been continuously focused on in recent years. This critical review discusses the development of AM technologies and materials, cellulose-based polymers, cellulose-based three-dimensional (3D) printing filaments, liquid deposition modeling of cellulose, and four-dimensional (4D) printing of cellulose-based materials. Cellulose-based AM material applications and the limitations with future developments are also reviewed. 2020 by the authors.

Absorption is one of the effective, simple and economical methods to remove oil from oily wastewater. The most widely used approach is to utilize lignocellulosic biomass as oil absorbent. However, the hygroscopic of cellulose have limited the oil-water separation capability of lignocellulosic fibers. In this study, the surface functionality of oil palm empty fruit bunch (EFB) fibers was slightly altered by grafting reduced graphene oxide (rGO). The modified EFB fibers show a distinct morphological and chemical characteristics changes as the surface of fibers has been coated with rGO. This was supported by FTIR analysis with the diminishing peak of hydroxyl group region of EFB fibers. While the surface modification on EFB fibers shows a diminution of a hydrophilic characteristic of 131.6% water absorption in comparison with 268.9% of untreated EFB fibers. Moreover, modified fibers demonstrated an oil-water separation increment as well, as it shows 89% of oil uptake and improved ~17 times of oil selectivity in oil-water emulsion than untreated EFB fibers.

Regenerated kenaf cellulose membranes were prepared by dissolving cellulose in a cellulose solvent of sodium hydroxide and urea, followed by coagulating in a sulfuric acid (H2SO4) solution. Different coagulant concentrations and coagulation reaction times were applied to study the morphology, physical and mechanical properties of the prepared cellulose membrane. The crystallinity index, surface morphology, mechanical performance and transparency of cellulose membrane were evaluated using X-ray diffraction (XRD), variable pressure scanning electron microscopy (VPSEM), tensile tests and UV-visible spectroscopy (UV-Vis), respectively. The results revealed changes in the pore size of the cellulose membranes, which were correlated with the concentration of sulfuric acid coagulant. However, the pore size of the membranes was not significantly affected by the coagulation time. Cellulose membranes that had been coagulated in lower concentration sulfuric acid with moderate coagulation time showed desirable mechanical properties. Thus, this study reports a favorable reaction time and coagulant concentration to fabricate regenerated cellulose membranes with desired physical properties. � 2018 Editura Academiei Romane. All rights reserved.

The recognition of cellulose nanofibrils (CNF) in the past years as a high prospect material has been prominent, but the impractical cellulose extraction method from biomass remained as a technological barrier for industrial practice. In this study, the telescopic approach on the fractionation of lignin and cellulose was performed by organosolv extraction and catalytic oxidation from oil palm empty fruit bunch fibers. The integration of these techniques managed to synthesize CNF in a short time. Aside from the size, the zeta potential of CNF was measured at ?41.9 mV, which allow higher stability of the cellulose in water suspension. The stability of CNF facilitated a better dispersion of Fe(0) nanoparticles with the average diameter size of 52.3�73.24 nm through the formulation of CNF/Fe(0). The total uptake capacity of CNF towards 5-fluorouracil was calculated at 0.123 mg/g. While the synergistic reactions of adsorption-oxidation were significantly improved the removal efficacy three to four times greater even at a high concentration of 5-fluorouracil. Alternatively, the sludge generation after the oxidation reaction was completely managed by the encapsulation of Fe(0) nanoparticles in regenerated cellulose. � 2019, The Author(s).