Publications

In this communication, we demonstrate the proof of concept that carbon nanocapsules (CNCs) can be used as an effective fluorescent sensing platform for nucleic acid detection with selectivity down to single-base mismatch. The detection is accomplished by two steps: (1) CNC adsorbs and quenches the fluorescence of the dye-labeled single-stranded DNA (ssDNA) probe; (2) in the presence of the target, a hybridization event occurs, which produces a double-stranded DNA (dsDNA) that detaches from the CNC surface, leading to recovery of the dye fluorescence.

The development of polymer nanocomposites by incorporating variable nanofillers has attracted attention of scientists, researchers and industrial sectors due to their dramatic improvement in various properties. Cellulose acetate (CA) based nanocomposites have interesting history in the field of medical applications because CA meets a wide range of biomedical implant properties. Since cellulose acetate is considered as a biodegradable, renewable, non-corrosive, non-toxic and biocompatible material, it raised up the unique advantages over many other materials. This review is designed to provide a broad overview of cellulose acetate nanocomposites in the field of medical applications and medical devices.

ASLAM JAMAL, MOHAMMED MUZIBUR RAHMAN, SHER BAHADAR KHAN*, MOHAMMED MARGUB ABDULLAH, MOHD FAISAL, ABDULLAH MUHAMMAD ASIRI, AFTAB ASLAM PARWAZ KHAN, KALSOOM AKHTAR Centre for Advanced Materials and Nano-Engineering (CAMNE) and Department of Chemistry, Faculty of Sciences and Arts, Najran University, P. O. Box 1988, Najran, 11001, Kingdom of Saudi Arabia. Center of Excellence for Advanced Materials Research (CEAMR), King Abdulaziz University, Jeddah 21589, P.O. Box 80203, Saudi Arabia. Chemistry Department, Faculty of Science, King Abdulaziz University, Jeddah 21589, P.O. Box 80203, Saudi Arabia. Division of Nano Sciences and Department of Chemistry, Ewha Womans University, Seoul 120-750, Korea. drkhanmarwat@gmail .com*

To overcome the key challenges associated with cement dust, such as inhalable size, toxic ions, and the existence of large quantities of useless materials, researchers investigated an innovative and unusual conversion of toxic cement dust into Mayenite nanoparticles. Mayenite is a natural structure that can be used as a filler in a variety of industrial applications. The formation of Mayenite nanoparticles was achieved through a thermal reaction at 1000°C for 2 h between cement dust and aluminum oxide. Different techniques were used to characterize the synthesized Mayenite nanoparticles, revealing the formation of the target phase as well as the reduction of toxic ions present in cement dust. According to Scherrer's equation, the crystallite size of bypass and synthesized Mayenite nanoparticles is 45 and 30 nm, respectively. Also, with the aid of TEM analysis, the particle size distribution of the produced Mayenite nanoparticles was found to be 27±7 nm. The toxic ions, especially chlorides and sulphates, were reduced by 86% and 50%, respectively, according to X-ray fluorescence results. These findings are important for the future use of Mayenite, 12CaO.7Al₂O₃ (C12A7), nanoparticles formed from toxic cement dust recycling.

In this contribution, a significant catalyst based on spinel ZnMn2O4 composite nanoparticles has been developed for electro-catalysis of nitrophenol and photo-catalysis of brilliant cresyl blue. ZnMn2O4 composite (hetaerolite) nanoparticles were prepared by easy low temperature hydrothermal procedure and structurally characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) and UV-visible spectroscopy which illustrate that the prepared material is optical active and composed of well crystalline body-centered tetragonal nanoparticles with average size of ∼ 38 ± 10 nm. Hetaerolite nanoparticles were applied for the advancement of a nitrophenol sensor which exhibited high sensitivity (1.500 µAcm(-2) mM(-1)), stability, repeatability and lower limit of detection (20.0 µM) in short response time (10 sec). Moreover, hetaerolite nanoparticles executed high solar photo-catalytic degradation when applied to brilliant cresyl blue under visible light.

S-scheme-based hydrothermal synthesis of SiO2@CuFe2O4-AgI composites was effectively described in this work. The photo-degradation of hazardous dyes like methylene blue (MB) and methyl orange (MO) was utilized to test nanocomposites with variable weight percent of AgI for photocatalytic activity in the visible range. In terms of photocatalytic activity, SiO2@CuFe2O4-AgI with a 15% AgI loading beat both pure and hybrid composites. In terms of MO degradation, the hybrid composite with 15% AgI loading degrades 16 times and 8 times faster than pristine CuFe2O4 and AgI samples, respectively, while in terms of MB degradation, it degrades 18.67 times faster and 9.33 times faster than pristine samples. The increased surface area decreased the recombination rate of photogenerated e− -h+ pairs, quicker separation of photogenerated carriers, and high redox capacity of SiO2@CuFe2O4-AgI (15%) all contribute to improved photocatalytic performance. The hybrid composite is chemically stable and reusable even after 10 cycles. Because of the coordinated Fermi level between CuFe2O4 and AgI, SiO2 acts as a transfer bridge for electrons in a layered structure. Furthermore, the scavenger experiment demonstrates that •O2-, •OH, and h+ are significant reactive species that efficiently aided the photodegradation of dyes. Current research proposes a novel and cost-efficient method for creating a stable semiconductor-based photocatalytic system and a viable strategy for future applications.

Conjugated polyelectrolyte/MWCNT/poly(pyrrole) (CPE-K/MWCNT/PPY) composites have been prepared by a simple solution mixing technique. Synthesis of PPY/CPE/MWCNT composites was characterized by scanning electron microscopy and thermogravimetric analysis. These nanocomposites of CPE-K/MWCNT/PPY were deposited onto a glassy carbon electrode (GCE) in order to fabricate a reliable Mg2+ cationic sensor. A plot called the calibration curve is produced from the current as a function of concentration of Mg2+ ion. This plot was found to be linear in the range 0.1 nM to 0.01 mM, which is defined as the linear dynamic range. According to the surface area of the GCE (0.0316 cm2) and the slope of the calibration curve, a high sensitivity (19.4968 µA µM–1 cm–2) of the Mg2+ ion sensor was calculated. A significant lower limit of detection (97.71 ± 4.89 pM) was obtained in association with a signal to noise ratio of 3. Sensor parameters such as reproducibility, long-time stability, and short response time were measured and found to be quite satisfactory. This new approach to Mg2+ detection with high sensitivity is suggested for application as a novel multifunctional sensing system. Besides, it was found to be very effective to analyze real environmental samples.