Muhammad Fakhar-E-Alam

Plasma based technologies are superior to traditional methods, achieving lower processing temperatures, fewer defects and better control of material properties and are efficient platforms for the synthesis of nanomaterials. The chapter aims to give an overview of plasma nanostructures covering their fabrication, characterization and applications. Plasma derived nanomaterials are carbon based (CNTs, graphene, CQDs, nanodiamonds) and metal and metal oxide nanostructures, plasma polymerized films and 2D materials such as MoS2 and hexagonal boron nitride. The major synthesis techniques studied and discussed are arc discharge, microwave plasma enhanced CVD and atmospheric pressure plasma with a focus on resulting structures. Electron microscopy, Raman spectroscopy, XPS and in-situ plasma diagnostics are also discussed. This chapter emphasizes on the wide range of applications of plasma nanostructures in the energy, biomedical and environmental fields, such as solar cells, supercapacitors, lithium-ion batteries, wound healing, cancer treatment, plasma activated liquids and drug delivery.

Cobalt ferrite (CoFe₂O₄) nanoparticles (NPs) have become one of the most extensively studied spinel ferrites due to their remarkable physicochemical characteristics, such as high magneto crystalline anisotropy, excellent coercivity, notable chemical stability, adjustable optical band gap (1.3–1.9 eV), and significant saturation magnetization (50-80 emu/g). These inherent properties, further improved through cationic substitution and the formation of nanocomposites, make CoFe₂O₄ NPs highly adaptable for a wide range of technological uses. This review offers a thorough and up-to-date examination of the synthesis, structural characteristics, effects of elemental substitution, and various applications of CoFe₂O₄ NPs and their nanocomposites (NCs). The primary synthesis methods such as co-precipitation, sol-gel auto combustion, microemulsion, solvothermal, hydrothermal, and ceramic techniques are thoroughly assessed regarding control over particle size, level of crystallinity, and scalability. The effect of replacing main group elements, first and second transition series metals, and lanthanides on the structural, magnetic, electrical, and catalytic characteristics of CoFe₂O₄ is examined in detail. Various characterization techniques including XRD, FTIR, SEM/TEM, VSM, BET, and XPS are described to clarify the relationships between structure and properties. The applications assessed include environmental remediation techniques, biomedical applications, and energy storage solutions. The review highlights that strategic design of nanocomposites and precise substitution are essential methods for tackling the inherent drawbacks of unmodified CoFe₂O₄ and realizing its complete multifunctional capabilities.

Microorganisms that are infected by bacteria and viruses require good substitutes to traditional antimicrobial remedies. In this chapter, the authors discuss plasma irradiation specifically non-thermal (cold) plasma as a promising antiviral and antibacterial technology, plasma jet, and microwave plasma systems. The production of reactive oxygen and nitrogen species (ROS/RNS), UV radiation, and charged particles by the plasma all degrade microbial cell walls, membranes, and nucleic acids, which allows inactivation on a broad spectrum. The chapter discusses the major operating parameters that control efficacy and uses in both medical sterilization, food safety, water purification and biofilm control. Its benefits, such as its chemical-free operation, low temperature, and its environmental compatibility, place plasma as a strong alternative to the conventional methods of sterilization. New technologies such as plasma-activated water (PAW) hybrids of plasma nanomaterials, are talked about as well as the recent issues like equipment price and low penetration.

In this research, we developed undoped and aluminum-doped zinc oxide for antimicrobial and anticancer activities. This study focuses on the synthesis, characterization, and biological activities of zinc oxide nanoparticles (ZnO NPs) and aluminum-doped zinc oxide nanocomposites (Zn_1−xAl_xO NCs) at varying concentrations (x = 0, 0.25, 0.5, and 0.75 wt%) using the coprecipitation method. Various characterization techniques such as XRD, UV-Vis, FTIR, EDX, and SEM were performed to analyze the crystal structure, optical properties, functional group identification, elemental composition, and surface morphology. The antimicrobial activity test showed that Zn_0.75Al_0.25O NCs exhibited the strongest inhibition zone against Bacillus cereus compared to Staphylococcus aureus > Pasteurella multocida > Escherichia coli. Moreover, the cytotoxicity and cell viability of liver cancer (HepG-2), breast cancer (MCF-7), ovarian cancer (SKOV3), and normal liver cell lines) were evaluated using the MTT assay, demonstrating that Zn_0.75Al_0.25O NCs not only enhance cell destruction but also show low cytotoxicity and high biocompatibility at low concentrations. These results suggest that Zn_0.75Al_0.25O NCs could be a promising candidate for in vivo anticancer applications and should be further investigated.

Silver oxide (Ag₂O) particles are wonderful candidates due to their unique properties, and their use in a wide range of research, industrial and biomedical applications is rapidly increasing. This makes it fundamental to develop simple, environmentally friendly methods with possible scaling. Herein, sodium borohydride and Datura innoxia leaf extract were applied as chemical and biological stabilizing and reducing agents to develop Ag₂O particles. The primary aim was to evaluate the anticancer and antiviral activity of Ag₂O particles prepared via two methods. XRD, UV-visible and SEM analyses were used to examine the crystallite structure, optical properties and morphology, respectively. The resulting green-synthesized Ag₂O particles exhibited small size, spherically agglomerated shape, and high anticancer and antiviral activities compared to chemically synthesized Ag₂O particles. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium-bromide) assay of green-synthesized Ag₂O particles showed high anticancer activity against MCF-7 cells with IC₅₀ = 17.908 µg/mL compared to chemically synthesized Ag₂O particles with IC₅₀ = 23.856 µg/mL. The antiviral activity of green-synthesized Ag₂O particles and chemically synthesized Ag₂O particles was also evaluated by a plaque-forming assay, and green-synthesized Ag₂O particles showed higher antiviral ability with IC₅₀ = 0.618 µg/mL as compared to chemically synthesized Ag₂O particles with IC₅₀ = 6.129 µg/mL. We propose the use of green-synthesized Ag₂O particles in cancer treatment and drug delivery.

Bilayer electrospun fibers aimed to be used for skin tissue engineering applications were fabricated for enhanced cell attachment and proliferation. Different ratios of PHBV-PLLA (70:30, 80:20, and 90:10 w/w) blends were electrospun on previously formed electrospun PHBV membranes to produce their bilayers. The fabricated electrospun membranes were characterized with FTIR, which conformed to the characteristic peaks assigned for both PHBV and PLLA. The surface morphology was evaluated using SEM analysis that showed random fibers with porous morphology. The fiber diameter and pore size were measured in the range of 0.7 ± 0.1 µm and 1.9 ± 0.2 µm, respectively. The tensile properties of the bilayers were determined using an electrodynamic testing system. Bilayers had higher elongation at break (44.45%) compared to the monolayers (28.41%) and improved ultimate tensile strength (7.940 MPa) compared to the PHBV monolayer (2.450 MPa). In vitro cytotoxicity of each of the scaffolds was determined via culturing MC3T3 (pre-osteoblastic cell line) on the membranes. Proliferation was evaluated using the Alamar Blue assay on days 3, 7, and 14, respectively. SEM images of cells cultured on membranes were taken in addition to bright field imaging to visually show cell attachment. Fluorescent nuclear staining performed with DAPI was imaged with an inverted fluorescent microscope. The fabricated bilayer shows high mechanical strength as well as biocompatibility with good cell proliferation and cell attachment, showing potential for skin substitute applications.