Novel formulation for co-delivery of cinnamon- and cumin-loaded polymeric nanoparticles to enhance their oral bioavailability

Nanobiotechnology has been an encouraging approach to improving the efficacy of hydrophobic bioactive compounds. The biologically active constituents present in herbal extracts are poorly absorbed, resulting in loss of bioavailability and efficacy. Hence, herbal medicine and nanotechnology are combined to overcome these limitations. The surface-to-volume ratio of nanoparticles is high and as the size is small, the functional properties are enhanced. The present study reports the synthesis of cinnamon and cumin (Ci–Cu) dual drug-loaded poly (D, L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) to overcome the limitations of oral bioavailability and extend the effect of these drugs for alleviating health problems. The solvent evaporation method was adopted for the synthesis, and the as-prepared nanoparticles were characterized by Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, Transmission electron microscopy (TEM) and X-ray diffraction (XRD). The average size of the formed spherical Ci-Cu nanoparticles ranged between 90 and 120 nm. The encapsulation efficiency of the drug was found to be 79% ± 4.5%. XRD analysis demonstrated that cinnamon and cumin were amorphously scattered in the PLGA matrix. The FTIR bands showed no evident changes suggesting the no direct molecular interactions between the drug and the polymer. At pH 6.9, the release studies in vitro exhibited a burst initially followed by a tendency to obtain a slower steady release. The results indicated that the Cu-Ci dual drug-loaded polymeric NPs has drug release at a slower rate. The time taken for 25% release of drug in Ci-Cu-loaded PLGA NPs was twice as compared to cumin-loaded PLGA Nps, and three times compared to cinnamon-loaded PLGA NPs.Open Access funding provided by the Qatar National Library. This study was funded by the Qatar University, Kishor Kumar Sadasivuni Grant no: QUCG-CAM-21/22-1.Scopu

High-Precision Nonenzymatic Electrochemical Glucose Sensing Based on CNTs/CuO Nanocomposite

The measurement of blood glucose levels is essential for diagnosing and managing diabetes. Enzymatic and nonenzymatic approaches using electrochemical biosensors are used to measure serum or plasma glucose accurately. Current research aims to develop and improve noninvasive methods of detecting glucose in sweat that are accurate, sensitive, and stable. The carbon nanotube (CNT)-copper oxide (CuO) nanocomposite (NC) improved direct electron transport to the electrode surface in this study. The complex precipitation method was used to make this NC. X-ray diffraction (XRD) and scanning electron microscopy were used to investigate the crystal structure and morphology of the prepared catalyst. Using cyclic voltammetry and amperometry, the electrocatalytic activity of the as-prepared catalyst was evaluated. The electrocatalytic activity in artificial sweat solution was examined at various scan rates and at various glucose concentrations. The detection limit of the CNT-CuO NC catalyst was 3.90 µM, with a sensitivity of 15.3 mA cm−2 µM−1 in a linear range of 5–100 µM. Furthermore, this NC demonstrated a high degree of selectivity for various bio-compounds found in sweat, with no interfering cross-reactions from these species. The CNT-CuO NC, as produced, has good sensitivity, rapid reaction time (2 s), and stability, indicating its potential for glucose sensing.This publication was supported by Qatar University internal (Grant No. QUCG-CAM-21/22-1). The findings herein are solely the responsibility of the authors.Scopu

Comparison study of metal oxides (CeO2, CuO, SnO2, CdO, ZnO and TiO2) decked few layered graphene nanocomposites for Dye-Sensitized solar cells

Recent research is focused on few layered graphene (FLG) with various metal oxides (MOs) as (MOs; CeO2, CuO, SnO2, CdO, ZnO, and TiO2) nanocomposite materials are alternatives to critically important in the fabrication of solar cell devices. In this work, FLG with different MOs nanocomposites were prepared by a novel eco-friendly viable ultrasonic assisted route (UAR). The prepared FLG/MO nanocomposites were performed with various characterization techniques. The crystal and phase compositional were carried out through using X-ray diffraction technique. Surface morphological studies by field emission scanning electron microscope (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM). Spectroscopic methods were done by Raman and UV-Vis Diffuse reflectance spectra (UV-DRS). The prepared FLG/MO nanocomposites materials were used as a photoanode, in the fabrication of dye sensitized solar cells (DSSCs). Compared to TiO2 nanoparticles (NPs) and other FLG/MO nanocomposites, FLG/TiO2 nanocomposites exhibited superior photovoltaic properties. The ob-tained results indicate that FLG/TiO2 nanocomposites significantly improved the power conversion efficiency (PCE) of DSSCs. The photovoltaic analyses were performed in a solar simulator with an air mass (AM) of 1.5 G, power density of 100 m W/m2, and current density-voltage (J-V) was investigated using N719 dye.Funding: ?This research was funded by QATAR NATIONAL RESEARCH FUND (QNRF), grant number NPRP: 12S-0131-190030? and ?The APC was funded by QATAR NATIONAL RE-SEARCH FUND (QNRF)?.Scopu

Improvement of heat sink performance using paraffin/graphite/hydrogel phase change composite coating

Phase-change materials offer high latent heat and are widely used for energy storage applications. Paraffin wax is usually used as a phase-change material. However, its application in energy storage is restricted due to its low thermal conductivity. In the present work, graphite and graphite-hydrogel are used to enhance the thermal conductivity and heat release properties of paraffin wax. Wax-graphite (W-G) and wax-graphite-hydrogel (W-G-H) composites were synthesized by the dispersion of graphite and graphite-hydrogel in paraffin wax above its melting temperature. Scanning electron microscope (SEM) analysis was used to investigate the graphite and graphite-hydrogel distribution in the paraffin wax matrix. Thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) characterization were performed to measure the thermal stability and phase transition properties, respectively. DSC revealed that all composites have a similar melting temperature. The W-G-H composite displayed nearly 12 folds more thermal conductivity compared to the pure paraffin wax. High temperature brings adverse impacts on energy efficiency, and even destroys a semiconductor device. The synthesized W-G-H composite is proposed to decrease the working temperature of semiconductor devices. As an applicative demonstration, the W-G-H composite film was coated at the back of the solar panel. The W-G-H composite coated solar panel displayed a surface temperature that was near ∼4 °C lower than the bare solar panel while operating. The real-time experiment indicates that the W-G-H composite has high thermal conductivity and heat release properties. The study reports fundamentally new low-cost, simple, scalable, and self-adaptive, passive cooling technology to the semiconductor industry. The proposed material can further be developed in the form of paint and its heat sink properties can be improved by introducing hydrogels doped with Li+ and Br− ions.This work was supported by Qatar National Research Fund under the grant no. NPRP12S-0131-190030 . Open Access funding was provided by the Qatar National Librar

A Smart Colorimetric Platform for Detection of Methanol, Ethanol and Formic Acid

Carbon dioxide (CO2 ) is a greenhouse gas in the atmosphere and scientists are working on converting it to useful products, thereby reducing its quantity in the atmosphere. For converting CO2, different approaches are used, and among them, electrochemistry is found to be the most common and more efficient technique. Current methods for detecting the products of electrochemical CO2 conversion are time-consuming and complex. To combat this, a simple, cost-effective colorimetric method has been developed to detect methanol, ethanol, and formic acid, which are formed electrochemically from CO2 . In the present work, the highly efficient sensitive dyes were successfully established to detect these three compounds under optimized conditions. These dyes demonstrated excellent selectivity and showed no cross-reaction with other products generated in the CO2 conversion system. In the analysis using these three compounds, this strategy shows good specificity and limit of detection (LOD, ~0.03-0.06 ppm). A cost-effective and sensitive Internet of Things (IoT) colorimetric sensor prototype was developed to implement these dyes systems for practical and real-time application. Employing the dyes as sensing elements, the prototype exhibits unique red, green, and blue (RGB) values upon exposure to test solutions with a short response time of 2 s. Detection of these compounds via this new approach has been proven effective by comparing them with nuclear magnetic resonance (NMR). This novel approach can replace heavy-duty instruments such as high-pressure liquid chromatography (HPLC), gas chromatography (G.C.), and NMR due to its extraordinary selectivity and rapidity.Funding: This research was funded by Qatar National Research Fund (a member of the Qatar Foundation) grant number NPRP11S-1221-170116 and the APC was funded by Qatar National Research Fund.Scopu

A Novel Design and Development of Multilevel Inverters for Parallel Operated PMSG-Based Standalone Wind Energy Conversion Systems

The article presents the new power conversion for parallel-operated wind energy conversion systems. It has been formulated by new multilevel inverter (MLI) topologies with reduced switch counts, lowered conduction losses and a very good output voltage spectrum. The wind energy conversion systems included permanent magnet synchronous generator (PMSG), a diode bridge rectifier, a conventional boost converter and a novel multilevel inverter connected to an isolated load. The power conversion utilizing a novel multilevel DC to AC converter has been proven for its better efficiency, voltage utilization and power quality. The integration of wind energy conversion systems has been explored in MATLAB Simulink, and the hardware setup does the authentication of the MLI structure.This work was supported by Qatar National Research Fund under the grant no. MME03-1226-210042. The statements made herein are solely the responsibility of the authors.Scopu

Self-sanitizing reusable glove via 3D-printing and common mold making method

In health care and public health practice, it is critical to settings control practices that are critical to reducing the transmission of infections through cross-contamination. To provide protection from cross-contamination, use and throw gloves are routinely used. However, single-time use and inconsistent sanitization of used gloves remain a large problem and elevate the risk of catching viruses, germs, pathogens, and contaminants. The study reports reusable self-sanitizing gloves via 3D-printing and common hand molding methods. The major contribution is frequent self-sanitization of gloves without any manual intervention. The elastomeric material is used for fabricating gloves and continuous channels are embedded within the elastomeric material that runs through the entire glove surface, covering the front, back, and fingers. Elastomeric material allows the engagement of fingers for gripping objects. While the embedded channel is provided with uniformly spaced openings to eject the sanitizing solution. The glove surface is textured with a porous morphology that acts as mini and micro reservoirs for sterilizing solution ejected through embedded channel opening. The embedded channel is connected to a sanitizing solution storage tank. The incorporation of sanitizing solution storage tank enables its usage over a longer period. This uniquely constructed design of the gloves even assists in the effective sterilization of infected surface that comes in contact with the gloves. The gloves can be customized to improve comfortability by fabricating them from the 3D-printed mound developed based on the palm size of the user. The developed technology can be used by individuals working in hospitals, the transport sector, delivery units, schools, offices, industries, etc. We strongly believe that this technology will be highly useful in minimizing the risk of getting infected through cross-contamination and will help in maintaining hygienic as well as safe surroundings.This work was supported by the RRC-2-063-133 grant from the Qatar National Research Fund (a member of Qatar Foundation). Open Access funding was provided by the Qatar National Library

Size-Independent Parameter for Temperature-Dependent Surface Plasmon Resonance in Metal Nanoparticles

Temperature (T)-dependent optical response of gold nanoparticle (NP) dimer of radii, 5-60 nm surrounded by air Medium is simulated and studied using finite element method (FEM). Temperature-dependent damping parameter from Drude-Lorentz dielectric model having contribution from different scattering, mechanisms and volume expansion is taken into,consicleration for studying surface plasmon resonance (SPR) behavior. A red shift and band broadening of SPR. is observed with increase in temperature for all sizes with significant shift for dimes of radii 40-60 nm. A size-independent parameter is extracted from the study, showing similar temperature-dependence, irrespective of dimer size, and can be used as an important parameter in temperature sensing

Optimization of electroless plating of gold during MACE for through etching of silicon wafer

Deep etching of silicon (Si) is very much desirable for wide variety of applications. Under the context, a cost effective and reproducible through etching of similar to 375 mu m thick Si wafer is demonstrated through long hour metal assisted chemical etching (MACE) followed by short duration KOH etching. During MACE, apart from pH and temperature, metal catalyst size and coverage density during electroless plating plays an important role. Optimization of gold deposition in terms of plating solution concentration and deposition time during MACE is studied for effective through etching. HAuCl4 concentration of similar to 5 mM for 30 s is found to be best suited for MACE and produces deep and highly dense pores in Si with threshold pore radius similar to 250 nm and above. Following the MACE, KOH etching effectively scoops out porous Si to realize through etching