Surface Modification of Alumina Nanoparticles: A Dispersion Study in Organic Media

Investigating the Reactive Reinforcement Ability of Maleic Anhydride-Modified Cellulose Nanocrystals via In-Situ Emulsion Polymerization

CNC-based nanocomposites have gained substantial interest because of their enhanced thermomechanical properties for high-end engineering applications. The chemical modification of CNCs expands their applicability, making them suitable for use in hydrophobic polymer matrices. The current study investigates the reactive reinforcing ability of maleic anhydride-modified cellulose nanocrystals during the in situ polymerization of a vinyl monomer, i.e., styrene. Highly crystalline nanocellulose (CNCBG) was isolated from Lagenaria siceraria (Bottle gourd) peels via Hydrochloric acid, which was further modified to synthesize maleic anhydride-modified cellulose nanocrystals (MACNCBG) and characterized employing various techniques. MACNCBG exhibited higher suspension stability than CNCBG due to the introduction of carboxyl groups. Furthermore, polystyrene-based nanocomposites of 3 and 5 wt % filler loading were prepared, respectively. While PSMACNCBG (5 wt %) displayed a premature failure, PSMACNCBG (3 wt %) demonstrated enhanced mechanical properties compared to PSCNCBG (3 wt %) and PS. At the same filler loading, MACNCBG demonstrated a more remarkable reinforcing ability than CNCBG, owing to its reactive tendency. The appearance of a new peak between 3000-2800 cm-1 corresponds to the C-H stretching of the formed C-C bond (between C=C of MACNCBG and benzal carbon of PS) in the FTIR spectra, confirming the reactive nature of MACNCBG.

Functionalized fennel extract-mediated alumina/cerium oxide nanocomposite potentiometric sensor for the determination of diclofenac sodium medication

The current work suggests a new, ultrasensitive green functionalized sensor for the determination of anti-inflammatory medication diclofenac sodium (DCF). Alumina (Al2O3) and cerium oxide (CeO2) nanoparticles (NPs) have attracted great interest for their use as outstanding and electroactive nanocomposite in potentiometric and sensory research due to their ultrafunctional potential. The formed nanoparticles have been confirmed using various spectroscopic and microscopic techniques. The fennel extract-mediated Al2O3/CeO2 nanocomposite (Al2O3/CeO2 NCS) modified coated wire membrane sensor developed in this study was used to quantify DCF in bulk and commercial products. Diclofenac sodium was coupled with phosphomolybdic acid (PMA) to generate diclofenac phosphomolybdate (DCF-PM) as an active ion-pair in the existence of polyvinyl chloride (PVC) and o-nitrophenyl octyl ether (o-NPOE). Clear peaks at 270, and 303 nm with band gaps of 4.59 eV and 4.09 eV were measured using UV-vis spectroscopy of Al2O3 and CeO2, respectively. The crystallite sizes of the formed nanoparticles were XRD-determined to be 30.13 ± 8, 17.72 ± 3, and 35.8 ± 0.5 nm for Al2O3, CeO2, and Al2O3/CeO2 NCS, respectively. The developed sensor showed excellent response for the measurement and assay of DCF, with a linearity between 1.0 × 10-9 and 1.0 × 10-2 mol L-1. EmV = (57.76) log [DCF] +622.69 was derived. On the other hand, the typical type DCF-PM presented a potentiometric response range of 1.0 × 10-5-1.0 × 10-2 mol L-1 and a regression equation of EmV = (56.97) log [DCF]+367.16. The functionalized sensor that was proposed was successful in determining DCF in its commercial tablets with percent recovery 99.95 ± 0.3. Method validation has been used to improve the suitability of the suggested potentiometric technique, by studying various parameters with respect to the international council harmonization requirements for analytical methodologies.

Innovative electrochemical electrode modified with Al2O3 nanoparticle decorated MWCNTs for ultra-trace determination of tamsulosin and solifenacin in human plasma and urine samples and their pharmaceutical dosage form

A simple, cheap, sensitive, and time-saving square wave voltammetric (SWV) procedure using a carbon paste electrode modified with aluminum oxide nanoparticle decorated multi-walled carbon nanoparticles (Al2O3-NPs/MWCNTs/CPE) is presented for the ultra-sensitive determination of tamsulosin (TAM) and solifenacin (SOL), one of the most prescribed pharmaceutical combinations in urology. Characterization of the developed electrode was performed using scanning electron microscopy (SEM), X-ray diffraction (XRD) patterns, energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM) and FT-IR spectrophotometry. The voltammetric behavior of TAM/SOL was evaluated using Al2O3-NPs in different content and electrode compositions. The use of Al2O3 functionalized MWCNTs as a CPE modifier increased the process of electron transfer as well as improved the electrode active surface area therefore, ultra-sensitive results were acquired with a linear range of 10-100 and 12-125 ng ml-1 for TAM and SOL respectively, and a limit of the detection value of 2.69 and 3.25 ng ml-1 for TAM and SOL, respectively. Interestingly, the proposed method succeeded in quantifying TAM and SOL with acceptable percentage recoveries in dosage forms having diverged concentration ranges and in the biological fluids with very low peak plasma concentration (C max). Furthermore, the proposed method was validated, according to the ICH criteria, and shown to be accurate and reproducible.

Green synthesis of nano-Al2O3, recent functionalization, and fabrication of synthetic or natural polymer nanocomposites: various technological applications

Environmentally friendly fabrication of nano-Al₂O₃, recent functionalization, and preparation of polymer nanocomposites including natural and man-made polymers with various industrial applications are reviewed.