Nehal Salahuddin - Academia.edu (original) (raw)

Papers by Nehal Salahuddin

Composites science and technology, 2022

Analytical Methods

A stripping voltammetric sensor for ultrasensitive detection of artesunate (ART) and dopamine HCl... more A stripping voltammetric sensor for ultrasensitive detection of artesunate (ART) and dopamine HCl (DA) has been successfully developed using a Ppy@ZnO/Fe3O4 core–shell nanocomposite ([PZM])-modified carbon paste sensor (MCPS).

Carbohydrate Polymers, 2022

Novel bio-based nanocomposites were developed as carriers for loading and sustained-release of va... more Novel bio-based nanocomposites were developed as carriers for loading and sustained-release of vanillin (Van.) and cinnamaldehyde (Cinn.) antioxidants. The composites were obtained by intercalation of chitosan (CS) into sodium montmorillonite (CS/Mt), incorporation of chitosan with polyaniline (CS/PANI) and chitosan/polyaniline/exfoliated montmorillonite (CS/PANI/Mt). The structure and morphology of composites were characterized by FTIR, XRD, SEM and TEM. The release data of Van. and Cinn. from CS and CS/Mt obeyed well zero-order equation. However, Higuchi and Korsmeyer-Peppas models fitted well the release data from CS/PANI and CS/Mt composites. Their antifungal activity was examined towards Fusarium oxysporum and Pythium debaryanum. In vitro assay, CS, Cinn., Van., CS/PANI and CS/PANI/Cinn., have a strong inhibitory effect on the linear growth of the target pathogens, even at lower concentrations. Greenhouse assay indicated that seedling treatment by the loaded CS/PANI/Cinn and CS/Mt/Cinn. reduced both disease index and disease incidence parameters of both pathogens and possessed seedlings growth promoting potential of tomato compared to untreated-infected controls.

ACS applied materials & interfaces, Jan 14, 2018

To overcome drug resistance, efficient cancer therapeutic strategies using a combination of small... more To overcome drug resistance, efficient cancer therapeutic strategies using a combination of small-molecule drugs and macromolecule drugs is highly desired. However, because of their significant differences in molecular weight and size, it is difficult to load them simultaneously in one vector and to release them individually. Here, a biodegradable organosilica-based core-shell-structured nanocapsule was designed and used as a dual stimuli-responsive drug vector to solve this problem. Biodegradable organosilica shell coated outside the macromolecule model drug "core" would be disrupted by high glutathione (GSH) levels inside tumor cells, resulting in the escape of the entrapped drugs. Small-molecule drugs capping on the surface of the organosilica shell via pH-responsive imine bonds can be cut and released in the acidic lysosomal environment. Transmission electron microscopy has shown that the framework of the organosilica shell was dissolved and degraded after 8 h incubati...

Colloids and Surfaces B: Biointerfaces, 2013

In the present work, a simple carboxylated multiwall carbon nanotubes (CMWCNTs) modified glassy c... more In the present work, a simple carboxylated multiwall carbon nanotubes (CMWCNTs) modified glassy carbon electrode was developed for sensitive determination of methyldopa (MTD). The study of modified electrode and MTD electrochemical behavior at its surface was investigated employing SEM, adsorptive stripping voltammetry, electrochemical impedance spectroscopy and chronocoulometry. These studies show that the oxidation of MTD is facilitated at the surface of GCE which is casted with CMWCNTs and remarkably peak current enhanced comparing to the bare electrode due to its adsorption on the electrode surface. Also, because of the catalytic property of modified electrode onset potential decreased for oxidation of MTD. Under optimized conditions, the calibration curve was linear in two concentration ranges of 0.1-30 and 30.0-300.0 μM with a detection limit of 0.08 μM and relative standard deviation (R.S.D.%) lower than 3.0% (n=5). This modified electrode was used as a sensor for determination of MTD in pharmaceutical and human urine samples with satisfactory results.

Journal of Molecular Structure

Advances in Polymer Technology, 2013

ABSTRACT In the present work, we explore the opportunity to deposit zinc sulfide (ZnS)/polyanilin... more ABSTRACT In the present work, we explore the opportunity to deposit zinc sulfide (ZnS)/polyaniline (PANI) composite films through an electrochemical route. The structural and the optical characterization showed the interaction between ZnS nanoparticular and PANI. The structure of the PANI–ZnS composite films was characterized by scanning electron microscopy, atomic force microscopy, and UV–vis spectroscopy. Cyclic voltammetry was used to investigate the electrochemical behavior of the resulting material. The existence of Zn and S on PANI–ZnS composite films was proved by the EDX-mapping method. The conductivity measurements of PANI–ZnS composite films and PANI were accomplished by the four-probe technique. © 2013 Wiley Periodicals, Inc. Adv Polym Technol 2013, 32, 21373; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21373

Journal of Advance Research in Pharmacy & Biological Science (ISSN: 2208-2360)

Chitosan (CS) 1,2,4-triazole derivatives including in the formulation tripolyphosphate (TPP) as c... more Chitosan (CS) 1,2,4-triazole derivatives including in the formulation tripolyphosphate (TPP) as crosslinking agent was prepared by a simple one step method using ultrasonic technique. The resultant nanoparticles were characterized by x-ray diffraction (XRD), Fourier transform infrared analysis (FT-IR), thermal gravimetric analysis (TGA), derivative thermal gravimetric analysis (D-TGA), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The results indicate that spherical nanoparticles with an average size of 21, 14.6, 23.95, 29.5 nm and their standard deviation (SD) were ±5, ±5.3, ±5.3, ±7.9 nm for CSTPP, CSTPPIII, CSTPPIV and CSTPPV, respectively were successfully prepared. The in vitro release and mechanism of 1,2,4-triazoles at different pH values was investigated. From values of R2 the mechanism of drug release is following zero order mechanism at pH 6.8; however in pH 2, CSTPPIII, CSTPPIV and CSTPPV are following Hixson-Crowell, zero order and Korsme...

Chemical Papers

The excellent antimicrobial and anticancer efficacy of zinc oxide nanoparticles (ZnO NPs) with st... more The excellent antimicrobial and anticancer efficacy of zinc oxide nanoparticles (ZnO NPs) with strong adsorption capability, low toxicity, low-cost and biocompatibility have spun these nanomaterials into one of the drug delivery systems. Herein, we prepared ZnO NPs with different morphologies and particle size using different methods. ZnO NPs were characterized by using Fourier transform infrared spectroscopy, X-ray diffraction, dynamic light scattering, zeta potential analyzer, scanning electron microscopy and transmission electron microscopy. Spheres with different average diameter ranged from 27 to 94.3 nm, flowers like shape with an average diameter of 250 nm, rod like shape with an average diameter of 92 nm, average length of 337 nm and a semispherical nanosheets with an average diameter of 49 nm were obtained. The nanoparticles were loaded by 5-fluorouracil as anticancer drug model. Adsorption capacity is influenced by the morphology and the size of nanoparticles. Kinetics using pseudo-first-order, pseudo-second-order and intra particle diffusion models was studied. Adsorption isotherms was explored using Langmuir, Freundlich and Temkin isotherm equations. Antibacterial activity of ZnO NPs onto gram-negative and gram-positive bacteria was studied by using disk diffusion agar method. The release of 5-fluorouracil from loaded ZnO NPs was studied at different pH media (2, 7.4) by using UV–visible spectrophotometer. 5-fluorouracil loaded ZnO NPs were examined against colon cancer (HCT) cell line. The spheres and flower-loaded drug showed higher efficacy than pure drug against colon cancer cell line. The results suggest that changing ZnO NPs morphology and particle size will affect antibacterial, anticancer activity, loading capacity of 5-fluorouracil and release profile.

zinc oxide nanotubes were prepared by a hydrothermal method using zinc nitrate as a precursor. Th... more zinc oxide nanotubes were prepared by a hydrothermal method using zinc nitrate as a precursor. The synthesized nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and their optical properties were characterized using UV -visible spectroscopy. The XRD analysis confirmed that the ZnO nanotubes have the hexagonal wurtzite structure. UV-vis absorption spectrum showed a typical spectrum of pure ZnO nanotubes. According to TEM analysis, the mean length and average outer diameter of the ZnO NTs were about 2.4 μm and 200 nm, respectively.

ACS Omega, 2021

Poly(aniline-co-o-anthranilic acid)-chitosan/silver@silver chloride (PAAN-CS/Ag@AgCl) nanohybrids... more Poly(aniline-co-o-anthranilic acid)-chitosan/silver@silver chloride (PAAN-CS/Ag@AgCl) nanohybrids were synthesized using different ratios of Ag@AgCl through a facile one-step process. The presence of CS led to the formation of the nanohybrid structure and prevented the aggregation of the copolymer efficiently. The synthesized nanohybrids were fully characterized by transmission electron microscopy, X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, and thermogravimetric analysis. (E)-N′-(Pyridin-2-ylmethylene) hydrazinecarbothiohydrazide I was prepared using thiosemicarbazide and confirmed by 1H-NMR, 13C-NMR, and FTIR analyses. Loading of the azine derivative I using various concentrations at different pH values onto the nanohybrid was followed by UV–vis spectroscopy. Langmuir and Freundlich adsorption isotherm models were used to describe the equilibrium isotherm, and the adsorption followed the Langmuir adsorption isotherm. A pseudo-second-order model was used to d...

Chitosan (CS)/Quinazolinone/Tripolyphosphate (TPP) nanoparticles have been synthesized using 2.3:... more Chitosan (CS)/Quinazolinone/Tripolyphosphate (TPP) nanoparticles have been synthesized using 2.3:1 molar ratio of CS/TPP in presence of quinazolinone derivatives (I-IV) through simple one step reaction. The mixture was subjected to ultrasonic waves to obtain the nanoparticles. The nanoparticles are quite uniform in size, spherical shape and rod like structure depending on the quinazolinone derivatives. The amount of loaded quinazolinone was calculated using UV-Vis spectrophotometer and TGA. The release of quinazolinone derivatives (I-IV) in acidic medium (pH=2) is significantly higher than in slightly acidic medium (pH=6.8). The proposed mechanism based on zero orders, first order, Higuchi, Hixson-Crowell and Korsmeyer-Peppas model equation are explored. The antimicrobial activity of nanoparticles was investigated against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus epidermis and Staphylococcus aureas.

Applied Clay Science

Abstract Eco-friendly adsorbent of chitosan–montmorillonite/polyaniline (CH–Mt/PANI) nanocomposit... more Abstract Eco-friendly adsorbent of chitosan–montmorillonite/polyaniline (CH–Mt/PANI) nanocomposite was synthesized by the intercalation of CH into Mt through ion-exchange process followed by the impregnation of aniline. Then in-situ polymerization of aniline using ammonium peroxydisulfate as an oxidant yielded a conducting polymer, polyaniline, as an additional component. The composite with polyaniline salt was also converted to corresponding CH–Mt/PANI base nanocomposite. The composites were characterized by Fourier transform infrared spectroscopy, X-ray diffractometry, thermal gravimetric analysis and electron microscopy and subsequently used for the removal of methylene blue from aqueous solutions. The composite with polyaniline base proved to be better dye adsorbent than that with polyaniline salt and was therefore investigated in detail. The adsorption of the dye onto CH–Mt/PANI base nanocomposite follows the pseudo second-order kinetics and it is well described by Temkin isotherm model. Moreover, the intraparticle diffusion was found to play a significant role in the adsorption mechanism. The maximum adsorption capacity was estimated to be 111 mg g−1, exceeded the adsorption capacities of the individual precursors.

RSC Advances

A targeted drug delivery system based on biocompatible magnetic hydrogel nanocomposites consistin... more A targeted drug delivery system based on biocompatible magnetic hydrogel nanocomposites consisting of poly[oligo(oxyethylene methacrylate)] anchored Fe3O4 nanoparticles was synthesized.

Handbook of Polymer Nanocomposites for Industrial Applications

Abstract Nanocomposites based on polymer materials enriched by relatively ultrafine and small amo... more Abstract Nanocomposites based on polymer materials enriched by relatively ultrafine and small amounts of nanostructures proved exceptionally promising materials. The preparation of nanocomposites includes three basic methods; melt blending, solvent method, and in situ polymerization techniques were discussed. This chapter deals with investigating the effect of zero-, one-, two-, and three-dimensional nanostructures on the properties of polymers. Polymer-inorganic nanocomposites owned massive interfacial surfaces as a unique property, which may outcome in distinctive physical frameworks. The main topics are concentrated on the applications of polymer nanocomposites as sensors and biosensors in the electroanalysis field due to their high stability, sensitivity, selectivity, and reproducibility. The sensors have been established for environmental evaluation especially for the recognition of metals, heavy metals, gases, and pesticides. In addition, the nanocomposite sensors were successfully used for detection of drugs in pharmaceutical formulation and biological fluids. Moreover electrochemical biosensors based on polymer nanocomposites were successfully developed for the detection of hormones, enzymes, and small biomolecules.