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Multimodal delivery system (MDS) or theranostic delivery system (TDS) is still at its infancy. In this work, the concept of MDS was employed, where magnesium/zinc aluminium-layered double hydroxides (Zn/Mg-Al LDH) and graphene oxide (GO) were used as nanocarriers (host) to intercalate and adsorb therapeutic agents (chlorogenic acid, prochatetuic acid and gallic acid), and contrast agents; gadolinium (Gd) as well as gold nanoparticles (AuNPs) as guest molecules. The Gd contrast agent was used as the main contrast agent for magnetic resonance imaging (MRI) and the AuNPs served as supporting contrast agent. The therapeutic and contrast agents were used to develop various the LDH and GO-based nanocomposites. The agents were developed based on ion exchange interaction in the LDH and non-covalent π-π stacking bonding and OH/COOH hydrogen bonding in the GO. The synthesis routes adopted were the Hummer’s modified method for GO and co-precipitation for LDH. The mechanism and physico-chemical properties of the nanocomposite formation were studied via characterization processes, such as transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM), which were used for shape, size and morphological studies. Fourier transformed-infrared spectroscopy (FTIR) and Raman spectroscopy were used for chemical interaction studies. Inductive coupled plasma emission spectroscopy (ICP‒ES), carbon, hydrogen, nitrogen and sulphur analysis (CHNS) and energy-dispersive X-ray (EDS) were used to study the composition as well as purity of the samples. The crystallinity and phase change was studied with X-ray diffraction (XRD) and the ultra violet – visible spectroscopy (UV-Vis) was used for drug release study. The anticancer efficacies of the nanocomposites and the pure phases were evaluated using human liver cancer cell lines (HepG2) and mouse fibroblast cell lines (3T3) were used in cytotoxicity studies. The inherent signal optimization was done on a 3 Tesla MRI

We have developed gadolinium-based theranostic nanoparticles for co-delivery of drug and magnetic resonance imaging (MRI) contrast agent using Zn/Al-layered double hydroxide as the nanocarrier platform, a naturally occurring phenolic compound, gallic acid (GA) as therapeutic agent, and Gd(NO3)3 as diagnostic agent. Gold nanoparticles (AuNPs) were grown on the system to support the contrast for MRI imaging. The nanoparticles were characterized using techniques such as Hi-TEM, XRD, ICP-ES. Kinetic release study of the GA from the nanoparticles showed about 70% of GA was released over a period of 72 h. The in vitro cell viability test for the nanoparticles showed relatively low toxicity to human cell lines (3T3) and improved toxicity on cancerous cell lines (HepG2). A preliminary contrast property test of the nanoparticles, tested on a 3 Tesla MRI machine at various concentrations of GAGZAu and water (as a reference) indicates that the nanoparticles have a promising dual diagnostic and therapeutic features to further develop a better future for clinical remedy for cancer treatment.

Copper nanoparticle synthesis has been gaining attention due to its availability. However, factors such as agglomeration and rapid oxidation have made it a difficult research area. In the present work, pure copper nanoparticles were prepared in the presence of a chitosan stabilizer through chemical means. The purity of the nanoparticles was authenticated using different characterization techniques, including ultraviolet visible spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. The antibacterial as well as antifungal activity of the nanoparticles were investigated using several microorganisms of interest, including methicillin-resistant Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella choleraesuis, and Candida albicans. The effect of a chitosan medium on growth of the microorganism was studied, and this was found to influence growth rate. The size of the copper nanoparticles obtained was in the range of 2-350 nm, depending on the concentration of the chitosan stabilizer.

In this study, chemical synthesis and characterization of Cu-NPs was carried out in the presence of two different stabilizers i.e. chitosan and starch polymer. The aim of this research is to individually synthesize, characterize, and test the antimicrobial activity of starch stabilized and chitosan stabilized Cu-NPs. The synthesis was carried out using aqueous medium in the presence of hydrazine as reducing agent, ascorbic acid as anti-oxidant, and sodium hydroxide as pH moderator. In determining the optimum conditions for the nanomaterials synthesis, temperature, stabilizer concentration, and reductant concentration were varied accordingly, i.e. 0.05, 0.1, 0.2 and 0.5 weight (wt)% by volume for stabilizers, 0.5, 1.0, 1.5 and 2.0 mL for hydrazine, range of 40, 80, 100 and 120°C for temperature. All the Cts/Cu-NPs and Stc/Cu-NPs synthesized were characterized using TEM, FESEM, FT-IR, UV-Vis, XRD and EDX. Following synthesis of the nanoparticles, antimicrobial analysis of the synthesized particles was investigated using different stabilizer concentrations. The UV−Vis spectroscopy results obtained for all samples showed significant surface plasmon resonance (SPR) peaks in the range of 500−600 nm, which indicated Cu-NPs formation. The molecular surface bonding of the nanoparticles and stabilizing media showed good interaction, which showed new bands at lower wave numbers (410, 600, 610 and 425), as revealed by the FT−IR spectra of all the samples. This indicates the capping of the nanoparticles by the polymers. The XRD diffractograms of samples obtained indicated high purity of the nanoparticles synthesized. No obvious peaks of CuO or Cu2O were observed. TEM analysis indicated size and size distribution of the nanoparticles differed based on the various parameters studied. FESEM micrographs of the synthesized Cu-NPs showed morphology of particles embedded within the polymer matrix. Spherical shaped nanoparticles were dominant while few hexagonal and rod-shaped were obse

Herein we report a synthesis of copper nanoparticles (Cu-NPs) in chitosan (Cts) media via a chemical reaction method. The nanoparticles were synthesized in an aqueous solution in the presence of Cts as stabilizer and CuSO4·5H2O precursor. The synthesis proceeded with addition of NaOH as pH moderator, ascorbic acid as antioxidant and hydrazine as the reducing agent. The characterization of the prepared NPs was done using ultraviolet-visible spectroscopy, which showed a 593 nm copper band. The Field Emission Scanning Electron Microscope (FESEM) images were also observed, and found to be in agreement with the UV-Vis result, confirming the formation of metallic Cu-NPs. The mean size of the Cu-NPs was estimated to be in the range of 35–75 nm using X-ray diffraction. XRD was also used in analysis of the crystal structure of the NPs. The interaction between the chitosan and the synthesized NPs was studied using Fourier transform infrared (FT-IR) spectroscopy, which showed the capping of the NPs by Cts.

Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. The use of plants in the green synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the green biosynthesis of silver nanoparticles using Callicarpa maingayi stem bark extract has been reported. Characterizations of nanoparticles were done using different methods, which include; ultraviolet-visible spectroscopy (UV-Vis), powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray fluorescence (EDXF) spectrometry, zeta potential measurements and Fourier transform infrared (FT-IR) spectroscopy. UV-visible spectrum of the aqueous medium containing silver nanoparticles showed absorption peak at around 456 nm. The TEM study showed that mean diameter and standard deviation for the formation of silver nanoparticles were 12.40 ± 3.27 nm. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc) structure. The most needed outcome of this work will be the development of value added products from Callicarpa maingayi for biomedical and nanotechnology based industries.