The unique properties of zinc oxide nanoparticles (ZnO-NPs) produced using plant extract make them attractive for use in medical as well as industrial applications, and it is necessary to develop environmentally friendly methods for their synthesis. This can be accomplished by replacing the traditional chemical compounds for the reduction of the zinc ions to ZnO-NPs during synthesis with natural plant extracts. Here, the biosynthesis of ZnO-NPs using Punica granatum (P. granatum) fruit peels extract was investigated as the reducing and stabilizing agent. The P. granatum/ZnO-NPs with spherical and hexagonal shapes were biosynthesized at different annealing temperatures. The X-ray diffraction analysis confirmed the synthesis of highly pure ZnO-NPs with increasing crystallinity in higher annealing temperatures. The ZnO-NPs displayed characteristic absorption peaks between 370 and 378 nm in the UV evis spectra. Transmission electron microscopy (TEM) imaging showed the formation of mostly spherical and hexagonal-shaped ZnO-NPs in the mean size of 32.98 nm and 81.84 nm at 600 C and 700 C respectively. According to FTIR spectrum, strong absorption bands in the range of 462e487 cm À1 corresponding to ZneO bond stretching can be seen. Antibacterial activities of P. granatum/ZnO-NPs against Escherichia coli (E. coli) and Enterococcus faecalis (E. faecalis) were investigated and compared. Results obtained show that smaller-sized P. granatum/ZnO-NPs are more effective in inhibiting growth of both bacteria. In addition, cytotoxicity assays were performed for P. granatum/ZnO-NPs against human colon normal and cancerous cells. P. granatum/ZnO-NPs exhibited similar killing activities of both cell lines at the concentration of !31.25 mg/mL. The biosynthesized ZnO-NPs could offer potential applications in biomedical field.

In this study, a comparative study of effect using honey on copper nanoparticles (Cu-NPs) via simple, environmentally friendly process and inexpensive route was reported. Honey and ascorbic acid act as stabilizing and reducing agents with the assistance of sonochemical method. The products were characterized using UV-visible (UV-vis) spectroscopy, X-Ray Diffraction (XRD), High-Resolution Transmission Electron Microscopy (HRTEM), Field-Emission Scanning Electron Microscopy (FESEM) and Fourier Transform Infrared (FTIR) spectroscopy. The reddish brown colour demonstrated the formation of Cu-NPs and UV-visible proved the plasmon resonance of Cu-NPs. XRD also confirmed a highly pure Cu-NPs obtained with absence of copper oxide in which the structure is crystalline. The spherical size of the Cu-NPs was acquire in the presence of honey which is 3.68 ± 0.78 nm with narrow particle distribution. The antibacterial activity was seen against gram-positive and gram-negative bacteria which are Enterococcus faecalis (E. faecalis) and Escherichia coli (E. coli). At higher concentration of Cu-NPs, they were more effective in killing both bacteria. The Cu-NPs without and with honey exhibited toxicities toward normal and cancerous cells. However, Cu-NPs without honey showed more potent killing activity against normal and cancer cells.

Photocatalytic activity of ZnO-NPs was tested by degradation of Malachite Green dye under UV light irradiation. The ZnO-NPs were biosynthesized using Punica granatum (pomegranate) fruit peels extract as the stabilizing agent. Simple sol-gel method and calcination in different temperatures (400, 500, 600 and 700°C) were carried out to obtain pure ZnO-NPs with high photocatalytic properties. In the degradation studies, 20 mg ZnO-NPs were used to degrade Malachite Green dye of 10 ppm initial concentration for a total period of 50 minutes in a 100 ml reaction volume. Results obtained shown that ZnO-NPs calcined in 700°C had the highest removal efficiency at about 99% in 40 minutes. This proves that biosynthesized ZnO-NPs have a high potential to be used as a photocatalyst to degrade textile dyes in a short time for wastewater treatments.

Chitosan nanoparticles (ChNPs) have been extensively examined for various biomedical applications due to their advantages include large surface area, biodegradability, and biocompatibility. The purpose of this research was to synthesize ChNPs using a simple ionic gelation technique by the interaction of low molecular weight chitosan (LMWC) and sodium tripolyphosphate (TPP) as a cross-linking agent. ChNPs, TPP, and LMWC were analysed by X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectra that indicated the formation of ChNPs, attributing to the rearrangement of the nanoparticles after adding the TPP cross-linker into the LMWC solution. XRD analysis exhibited that ChNPs were amorphous, due to the effect of TPP cross-linker. Dynamic light scattering showed the nano-dimension of ChNPs with a hydrodynamic size of 68.50 nm. Thus, the obtained results indicated that the properties of chitosan were improved through converting it into nanoparticles using TPP initiated ionic gelation procedure.

The combination of graphene-based materials and inorganic nanoparticles for the enhancement of the nanomaterial properties is extensively explored nowadays. In the present work, we used a sonochemical method to synthesize a copper/reduced graphene oxide (Cu/RGO) nanocomposite using Australian honey and vitamin C as capping and reducing agents, respectively. The honey-mediated copper/reduced graphene oxide (H/Cu/RGO) nanocomposite was then characterized through UV-visible, XRD, HRTEM, and FTIR analysis. The copper nanoparticles (Cu-NPs) in the nanocomposite formed uniform spherical shapes with a size of 2.20 ± 0.70 nm, which attached to the reduced graphene oxide (RGO) layers. The nanocomposite could suppress bacterial growth in both types of bacteria strains. However, in this study, the nanocomposite exhibited good bactericidal activity toward the Gram-positive bacteria than the Gram-negative bacteria. It also showed a cytotoxic effect on the cancer colorectal cell line HCT11, even in low concentrations. These results suggested that the H/Cu/RGO nanocomposite can be a suitable component for biomedical applications.

Chemotherapy is the most prominent route in cancer therapy for prolonging the lifespan of cancer patients. However, its non-target specificity and the resulting off-target cytotoxicities have been reported. Recent in vitro and in vivo studies using magnetic nanocomposites (MNCs) for magnetothermal chemotherapy may potentially improve the therapeutic outcome by increasing the target selectivity. In this review, magnetic hyperthermia therapy and magnetic targeting using drug-loaded MNCs are revisited, focusing on magnetism, the fabrication and structures of magnetic nanoparticles, surface modifications, biocompatible coating, shape, size, and other important physicochemical properties of MNCs, along with the parameters of the hyperthermia therapy and external magnetic field. Due to the limited drug-loading capacity and low biocompatibility, the use of magnetic nanoparticles (MNPs) as drug delivery system has lost traction. In contrast, MNCs show higher biocompatibility, multifunctional physicochemical properties, high drug encapsulation, and multi-stages of controlled release for localized synergistic chemo-thermotherapy. Further, combining various forms of magnetic cores and pH-sensitive coating agents can generate a more robust pH, magneto, and thermo-responsive drug delivery system. Thus, MNCs are ideal candidate as smart and remotely guided drug delivery system due to a) their magneto effects and guideability by the external magnetic fields, b) on-demand drug release performance, and c) thermo-chemosensitization under an applied alternating magnetic field where the tumor is selectively incinerated without harming surrounding non-tumor tissues. Given the important effects of synthesis methods, surface modifications, and coating of MNCs on their anticancer properties, we reviewed the most recent studies on magnetic hyperthermia, targeted drug delivery systems in cancer therapy, and magnetothermal chemotherapy to provide insights on the current development of MNC-based anticancer nanocarrier.

The activation of MNPs for hyperthermia therapy via an external alternating magnetic field is an interesting method in targeted cancer therapy. This mini-review explains new developments and implications of magnetic nanofluids mediated magnetic hyperthermia for their potential use in future clinical settings. The external alternating magnetic field generates heat in the tumor area to eliminate cancer cells. Depending on the tumor type and targeted area, several kinds of MNPs with different coating agents of various morphology and surface charge have been developed. The tunable physiochemical characteristics of MNPs enhance their heating capability. In addition, heating efficiency is strongly associated with the amount of the applied magnetic field and frequency. The great efforts have offered promising preclinical trials of magnetic hyperthermia via MNPs as a smart nanoagent. MNPs are very appropriate to be considered as a heating source in MHT and prospective research in this field will lead to tackle the problems from chemotherapy and introduce promising therapeutic techniques and nanodrug formulations for remotely controlled drug release and anticancer effects. This mini-review aims to pinpoint synthesis and structural analysis of various magnetic nanoparticles examined for magnetic hyperthermia therapy and controlled drug release in cancer treatment.

Due to their biocidal activity properties, graphene based materials have been widely studied especially in biomedical, agriculture and water treatment process which focus on mitigating the microbial resistance problem. However, the antibacterial performance of these materials alone are relatively weak and need to be improved in order to enhance their biological activity. Copper nanoparticles is a low cost metal also has the antibacterial properties which is almost similar with the silver and gold nanoparticles. The combination of these two materials had produced to a new potential material as another alternative for the antibacterial agents. Therefore, in this work, a brief review of copper/graphene based material nanocomposites and their antibacterial study was discussed.