In this study, an eco-friendly biosynthesis of stable gold nanoparticles (T-GNPs) was carried out using different concentrations of tomato juice (nutraceuticals) as a reducing agent and tetrachloroauric acid as a metal precursor to explore their potential application in cancer therapeutics. The synthesis of T-GNPs was monitored by UV-visible absorption spectroscopy, which unveiled their formation by exhibiting the typical surface plasmon absorption maxima at 522 nm. The size of T-GNPs was found to be 10.86 ± 0.6 nm. T-GNPs were characterised by dynamic light scattering, zeta potential, transmission electron microscopy analysis and Fourier transform infrared spectroscopy. T-GNPs were further investigated for their anti-cancer activity against human lung carcinoma cell line (A ₅₄₉) and human cervical cancer cell line wherein the IC₅₀ values were found to be 0.286 and 0.200 mM, respectively. T-GNPs inhibited the growth of cancer cells by generating ROS and inducing apoptosis. T-GNPs were found highly effective by virtue of their size, metallic property and capping molecules. Thus, this study opens up the prospects of using nutraceutical (tomato juice) as nutratherapeutic agent (T-GNPs) against critical diseases like lung cancer and cervical cancer.

Nanocarriers, in various forms, have the possibility of providing endless opportunities in the area of drug delivery. The purpose of this study was formulation and evaluation of betamethasone sodium phosphate (BSP) loaded chitosan nanoparticles (CNPs) using cross-linked chitosan malic acid derivative for better therapeutic effect. The prepared BSP loaded CNPs formulations were characterised for photon correlation spectroscopy, zeta potential, transmission electron microscopy, in-vitro release kinetics and in-vivo toxicity studies. Mean particle diameter of BSP loaded CNPs was about 130 nm with spherical morphology. The in-vitro drug release study of BSP loaded CNPs showed sustained drug release for 48 h and drug release was found to follow zero order. The biochemical, haematology and histopathology reports of in-vivo toxicity studies revealed that BSP loaded CNPs do not exhibit any toxic effect on vital organs and could be safe. The developed BSP loaded CNPs are found to be safer, and used for the treatments of highly prevalent and chronic disease like rheumatoid arthritis.

The aim of this study was preparation and optimisation of a controlled-release delivery system to decrease the dose-dependent side effects of gentamicin. Hydrogel nanoparticles composed of a polycationic polymer (chitosan) and an inorganic polyanion (sodium tripolyphosphate) were fabricated in the presence of gentamicin. An experimental design was drawn upon to determine the optimum condition of nanoparticle preparation. Various features of the nanoparticles including drug loading parameters, particle size distribution, zeta potential and in vitro drug release profile were evaluated. Ultimately, the antimicrobial activity of the gentamicin-loaded nanoparticles was analysed by determination of the minimum inhibitory concentration (MIC) and the potency test. As a result, the nanocarriers with an average size of about 250 nm (unloaded) and 493 nm (gentamicin-loaded) were obtained with unimodal distribution and a notable polydispersity index (≤0.3). The drug loading efficiency was between 28 and 32%. The gradual and sustained releases (∼90%) of gentamicin were achieved in 24 h. The MIC and potency test showed no significant decrease in the antibacterial activity of gentamicin-loaded nanoparticles. The outcomes demonstrated that the optimised chitosan nanogels prepared in this study can be considered as a suitable carrier for a controlled release system.

Silver phosphate nanoparticles were biologically synthesised, for the first time, using a dilute silver nitrate solution as the silver ion supplier, and without any source of phosphate ion. The applied bacterium was Sporosarcina pasteurii formerly known as Bacillus pasteurii which is capable of solubilising phosphate from soils. It was speculated that the microbe accumulated phosphate from the organic source during the growth period, and then released it to deionised water. According to the transmission electron microscopy images and X-ray diffraction results, the produced nanoparticles were around 20 nm in size and identified as silver phosphate nanocrystals. The outcomes were also approved by energy-dispersive X-ray analysis, thermogravimetric and differential scanning calorimetry analyses, ultraviolet–visible spectroscopy, and Fourier transform infrared spectroscopy analysis. Finally, the antibacterial effect of the obtained nanoparticles was verified by testing them against Bacillus cereus, Staphylococcus aureus, Escherichia coli, and Salmonella typhimurium. The activity of silver phosphate nanoparticles against gram-negative strains was better than the gram positives. It should be mentioned that the concentrations of 500 and 1000 mg/l were found to be strongly inhibitory for all of the strains.

We report new, eco-friendly and green method for the synthesis of sulphur nanoparticles using sodium polysulphide in the presence of leaf extracts of four different medicinal plants, which can be used for treatment of bacterial infections. Sodium polysulphide and acidic solution (H₂SO₄) in the presence of plant leaf extract developed the yellowish precipitate in solution, which indicated the formation of sulphur nanoparticles. UV–Vis spectrophotometer analysis of reaction mixture showed absorbance spectra in the range of 292–296 nm, which is supposed to be specific for sulphur nanoparticles. Zeta potential study of sulphur nanoparticles synthesized from Catharanthus roseus showed more stability when compared with other medicinal plants. Sulphur nanoparticles synthesized from C. roseus were further characterized by XRD analysis, FTIR analysis, and TEM analysis. The biogenic sulphur nanoparticles were spherical, polydispersed with particle size of 70–80 nm. Evaluation of antibacterial study revealed that synthesized sulphur nanoparticles exhibited better bactericidal efficacy against common pathogenic bacteria Escherichia coli and Staphylococcus aureus with minimum inhibitory concentration of 200 μg/ml with significant activity used in combination with antibiotic. It can be concluded that the synthesized sulphur nanoparticles can be used as antibacterial agents after thorough experimental trials in animals.

Actin is a biological protein that provides support to the cellular structure and plays a crucial role in cytoskeletal and intra-cellular signalling events. Logic circuits can be designed with actin filaments with the help of actin quantum automata. The authors use a rule (4,27) to implement some novel designs of logic subtractor circuits on this automata to achieve the difference in two binary bits. Logic design of both half and full binary subtractors is proposed in this study. Actin-based quantum cellular automata can be used in different combinations of input to get optimised results from the circuits. The authors focus on consolidating the designs inside single automata block to generate output in a less number of timesteps and less overheads. The designs are simulated with Simulink and this way output is verified for these different design approaches. Reliability and fault-tolerance check is another interesting part of this study. To get a better idea of the optimisation achieved, the authors have also presented a comparative study between the proposed designs in terms of circuit size and efficiency. With all these parameters involved, this study explores opportunities for future implementation of unconventional computing in nano-scale and cost-effective bio-molecular networks.

In this study, spontaneous synthesis of a gold (Au) colloid using cells of Cupriavidus metallidurans CH34 is reported, and compared with results obtained using cells of the model bacterium Escherichia coli MG1655. To investigate the synthesis mechanism, bacterial biomass and secretomes from both strains were incubated with Au(III) ions. Only CH34 cells were capable of producing extracellular dispersions of Au nanoparticles (NPs). Transmission electron microscopy images showed that AuNPs morphology was dominated by triangular and decahedral nanostructures. Energy dispersive X-ray spectroscopy and Fourier transform infrared spectra showed the presence of sulphur and vibrations associated to proteins. Average AuNPs diameter was obtained by dynamic light-scattering measurements (DLS), NP tracking analysis measurements and analysis of electron microscopy images. Moreover, DLS measurements showed that the biogenic colloid was stable after exposure to ultrasound, high ionic strength and extreme pH conditions. The biogenic AuNPs produced by strain CH34 did not show antibacterial activity, in contrast to biogenic silver NPs. Comparative bioinformatic analysis of genomes from strain CH34 and strain MG1655 showed potential CH34 proteins that may be electron donors during reduction of Au(III) ions. On the basis of these results, a mechanism for the extracellular Au reduction by strain CH34 is proposed.

The environmentally friendly synthesis of silver nanoparticles (AgNPs) has been achieved employing silver nitrate and sodium alginate (SA) without using other chemicals except for sodium hydrate. In the synthesis process, SA functions as both reductive and stabilising agent. The as-synthesised AgNPs size can be controlled just changing the reactive parameters such as the concentration of silver nitrate and SA, the solution pH, the reaction temperature and time. Formation of AgNPs was observed by the colour change in the reaction medium which was further established with UV–Vis spectroscopy. The characterisation of AgNPs infers that the as-synthesised AgNPs with an average size of 8.2 nm were spherical in shape and a face cubic crystal structure. The AgNPs-SA beads were easily prepared using AgNPs-SA nanocomposites due to SA crosslinking with metal ions. The catalytic efficiency of the resulting AgNPs beads is evaluated for the reduction of dyes such as 4-nitrophenol, methylene blue and reactive red in the presence of NaBH₄. Antibacterial efficacy of AgNPs was analysed against gram-negative Escherichia Coli and gram-positive Staphylococcus aureus by measuring the zones of inhibition on the solid growth medium. The as-synthesised AgNPs have shown efficient inhibitory activity against the tested bacterial strains.

Recently, attention has been given to nanocellulose produced by bacteria due to its unique properties and environmentally friendly nature when compared with plant cellulose. Bacterial nanocellulose (BNC) producing isolate was successfully isolated from rotten fruits via dilution and spread plates method. Based on the biochemical characterisation and molecular analysis of the 16S rDNA gene, the isolate was identified as Gluconacetobacter xylinus BCMZ sp. Nanocellulose productivity was confirmed by the formation of the white gelatinous layer between air/liquid surfaces when the culture was cultivated under a stationary condition at 30°C. Successful purification of nanocellulose was achieved using alkaline treatment method. The Fourier transformed infrared spectrum showed a characteristics band signature of pure nanocellulose, by displaying strong absorption peaks at 3335.36 and 2901.40 cm⁻¹ representing carbonyl and carbon–hydrogen bonding, respectively. Morphological characteristics of the BNC were determined by scanning electron microscopy (SEM). Elemental analysis of BNC was determined by energy dispersive X-ray (SEM/EDX) analysis. The isolates BCZM showed significant nanocellulose production ability with a high degree of purity when compared with plant nanocellulose. BNC purification using 1 M NaOH solution is effective and eco-friendly with no indication of recalcitrant formation as commonly found in plant nanocellulose purification steps.

Conventional hepatitis B vaccine contains alum but is less effective to induce Th1 response. Selenium nanoparticles and Bacillus Calmette–Guerin were reported as immune modulators. In this study, SeNPs were extracted from Mycobacterium bovis and characterised. SeNPs were mixed with HBs-Ag and administered to the mice to investigate he immune response pattern. With an addition of Se ions at a sub-inhibitory concentration to the Sauton medium broth after 24 h, SeNPs were extracted from M. bovis and characterised by Fourier transform infrared spectroscopy, dynamic light scattering, atomic forcemicroscopy, energy dispersive X-ray spectrum, transmission electron microscopy, and thermogravimetric analysis. Furthermore, female inbred BALB/c mice were injected subcutaneously on the first, 14th, 28th day with 100 and 200 µg doses of that SeNPs supplemented with HBs-Ag vaccine. Later, the total antibody, isotypes of Immunoglobulin G1, Interlukin 4, and interferon-γ were measured by enzye-linked immunosorbent assay. The size of the SeNPs was <150 nm. Level of total antibody and immunoglobulin G2a increased significantly in the group that received 200 µg/ml nano selenium extracted from M. bovis. SeNPs in dose of 200 µg coated with organic materials of M. bovis could induce an influential immune response in relation to the conventional HBs-Ag vaccine.

Extracellular biosynthesis of silver nanoparticles using five fungal species including Fusarium oxysporum and four others isolated from native lichens (Kerman, Iran) was investigated in this study. These fungal species were identified as Arctoparmelia incurva, Penicillium chrysogenum, Uncultured root-associated fungus, and Caloplaca arnoldii by using ITS rRNA sequence analysis. These species were then cultivated in four common industrial wastes, namely a combination of yeast and malt extract, sugar beet molasses, whey, and wastewater of beverage industry, prior to their use for biosynthesis. The synthesis of the nanoparticles was monitored by UV–visible spectroscopy. It was found to be significantly affected by both fungal species and their cultivation media. C. arnoldii cultivated in the yeast and malt extract resulted in the best performance regarding reaction kinetics, particle mean diameter and size distribution. The mean diameter and variance of the nanoparticles were determined to be about 11 nm and 24 by using transmission electron microscopy and powder X-ray diffraction techniques, respectively. The zeta potential of the nanoparticles was measured to be −21.5 mV confirming their long-term stability. These findings suggest a new biosynthetic route towards eco-friendly and inexpensive production of the nanoparticles in bulk.

Infectious diseases are caused by etiological agents. Nanotechnology has been used to minimise the effect of clinical pathogens which have resistance to antibiotics. In current research synthesis, characterisation and biological activities of green synthesised nanoparticles using Artemisia vulgaris extract have been done. The characterisation of AgNPs was carried out using Fourier transform infrared spectroscopy, UV-Vis spectrophotometry, and scanning electron microscopy. Anti-biofilm, cell viability, antibacterial, brine shrimp lethality, and deoxyribonucleic acid protection effects have been screened. UV-Vis spectra showed the absorption peak of synthesised nanoparticles at 400 nm. FT-IR indicated the involvement of the functional group in the preparation of AgNPs. SEM showed the spherical shape of AgNPs with 30 nm diameter. Biological screening results revealed the antibacterial effect against clinical bacterial pathogens. Biofilm reduction and cell viability assay also supported the antibacterial effect. Cytotoxicity effect was recorded as 100% at 200 μg/ml through brine shrimp lethality assay. Protein kinase inhibition zones recorded for AgNPs (16 mm bald) compared with A. vulgaris extract (11 mm bald). It has been concluded that green synthesised AgNPs are more effective against infectious pathogens and could be used as a potential source for therapeutic drugs.

Due to the strong effect of nanoparticles' size and surface properties on cellular uptake and bio-distribution, the selection of coating material for magnetic core–shell nanoparticles (CSNPs) is very important. In this study, the effects of four different biocompatible coating materials on the physical properties of Fe₃O₄ (magnetite) nanoparticles (NPs) for different biomedical applications are investigated and compared. In this regard, magnetite NPs are prepared by a simple co-precipitation method. Then, CSNPs including Fe₃O₄ as a core and carbon, dextran, ZnO (zincite) and SiO₂ (silica) as different shells are synthesised using simple one- or two-step methods. A comprehensive study is carried out on the prepared samples using X-ray diffraction, vibrating sample magnetometry, transmission electron microscopy and Fourier transform infrared spectroscopy analyses. According to the authors' findings, it is suggested that carbon- and dextran-coated magnetite NPs with high M _s have great potential in the application of magnetic resonance imaging contrast agents. Moreover, silica-coated magnetite NPs with high coercivity are potentially suitable candidates for hyperthermia and ZnO-coated Fe₃O₄ is potentially suitable for photothermal therapy.

We present an approach to functionalise optical microring resonators as hybridisation platforms, using tip-mould reactive microcontact printing process. Derived from reactive microcontact printing using an ad hoc mould of polydimethylsiloxane (PDMS), the method functionalises single microring resonator with a target-specific capture agent. The authors report the functionalisation of silicon nitride (SiN) diameter microring resonator with single-strand DNA and the hybridisation detection of 100 nM target analyte, while concurrently monitoring not-functionalised microring as a control sensor. Results show that the functionalisation approach permits to address single microring resonators with mutual distance lower than with high precision, enabling a better integration of multiple spotting zones on the chip concerning traditional functionalisation procedures.