From molecular biology to nanotechnology and nanomedicine

Responsive Supramolecular Polymers for Diagnosis and Treatment

Stimuli-responsive supramolecular polymers are ordered nanosized materials that are held together by non-covalent interactions (hydrogen-bonding, metal-ligand coordination, π-stacking and, host-guest interactions) and can reversibly undergo self-assembly. Their non-covalent nature endows supramolecular polymers with the ability to respond to external stimuli (temperature, light, ultrasound, electric/magnetic field) or environmental changes (temperature, pH, redox potential, enzyme activity), making them attractive candidates for a variety of biomedical applications. To date, supramolecular research has largely evolved in the development of smart water-soluble self-assemblies with the aim of mimicking the biological function of natural supramolecular systems. Indeed, there is a wide variety of synthetic biomaterials formulated with responsiveness to control and trigger, or not to trigger, aqueous self-assembly. The design of responsive supramolecular polymers ranges from the use of hydrophobic cores (i.e., benzene-1,3,5-tricarboxamide) to the introduction of macrocyclic hosts (i.e., cyclodextrins). In this review, we summarize the most relevant advances achieved in the design of stimuli-responsive supramolecular systems used to control transport and release of both diagnosis agents and therapeutic drugs in order to prevent, diagnose, and treat human diseases.

Meta-Analysis of Cytotoxicity Studies Using Machine Learning Models on Physical Properties of Plant Extract-Derived Silver Nanoparticles

Silver nanoparticles (Ag-NPs) demonstrate unique properties and their use is exponentially increasing in various applications. The potential impact of Ag-NPs on human health is debatable in terms of toxicity. The present study deals with MTT(3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium-bromide) assay on Ag-NPs. We measured the cell activity resulting from molecules' mitochondrial cleavage through a spectrophotometer. The machine learning models Decision Tree (DT) and Random Forest (RF) were utilized to comprehend the relationship between the physical parameters of NPs and their cytotoxicity. The input features used for the machine learning were reducing agent, types of cell lines, exposure time, particle size, hydrodynamic diameter, zeta potential, wavelength, concentration, and cell viability. These parameters were extracted from the literature, segregated, and developed into a dataset in terms of cell viability and concentration of NPs. DT helped in classifying the parameters by applying threshold conditions. The same conditions were applied to RF to extort the predictions. K-means clustering was used on the dataset for comparison. The performance of the models was evaluated through regression metrics, viz. root mean square error (RMSE) and R². The obtained high value of R² and low value of RMSE denote an accurate prediction that could best fit the dataset. DT performed better than RF in predicting the toxicity parameter. We suggest using algorithms for optimizing and designing the synthesis of Ag-NPs in extended applications such as drug delivery and cancer treatments.

Inorganic nanoparticles promoted synthesis of heterocycles

The application of inorganic nanoparticles as nanocatalyst for synthesizing of nitrogen containing heterocycles are reviewed. While an inclusive summary of the various catalysts utilized in the synthesis of heterocycles is demonstrated with limited focus on the preparation or characterization of the catalyst. The review is being summarized into different sections based on the size and the number of N-atoms in the cyclic compounds.

Produce of Selenium Nanoparticles by Pulsed Laser Ablation for Anticancer Treatments

The most serious public health problems now involve antibiotic resistance and cancer that kills more than 15 million people per year which indicates that the existing antibiotics and chemotherapy are not as active as before. This paper provides nanotechnology as a possible answer. However, typical physicochemical nanomaterials production processes, frequently requiring the use of harmful catalysts, have environmental or social implications. This paper covers how to use the innovative liquid-pulsed laser ablation (LP-PLA) process to manufacture selenium nanoparticles (SeNPs). After the first set of radiation at 500[Formula: see text]mJ laser energy and 100 pulses, a second set was employed to decrease the size to less than 100[Formula: see text]nm with the same condition. Therefore, two main groups of 80 and 10[Formula: see text]nm had colloidal solutions for spherical SeNPs. The particles were also more stable following the second round of irradiation. Furthermore, when SeNPs were grown with human dermal fibroblast cells at doses up to 1[Formula: see text]ppm, they had a mild cytotoxic impact. The potential of utilizing totally naked SeNPs produced using the novel LP-PLA procedure as a novel and efficient way of producing nanoparticles for biomedical applications is presented in this paper.

Automated identification and quantification of tire wear particles (TWP) in airborne dust: SEM/EDX single particle analysis coupled to a machine learning classifier

The share of non-exhaust particles, including tire wear particles (TWP), within the airborne dust and particularly within PM10 has increased in recent years due to a significant reduction of other particles including exhaust road traffic emissions. However, the quantification of TWP is a demanding task due to the non-specificity of tracers, and the fact that they are commonly contained in analytically challenging low concentrations (e.g. Zn, styrene, 1,3-butadiene, vinylcyclohexene). This difficulty is amplified by the chemical and morpho-textural heterogeneity of TWP resulting from the interaction between the tires and the road surface. In contrast to bulk techniques, automated single particle SEM/EDX analysis can benefit from the ubiquitous heterogeneity of environmental TWP as a diagnostic criterion for their identification and quantification. For this purpose, we follow a machine-learning (ML) approach that makes use of an extensive number (67) of morphological, textural (backscatter-signal based) and chemical descriptors to differentiate environmental particles into the following classes: TWP, metals, minerals and biogenic/organic. We present a ML-based model developed to classify airborne samples (trained by >100,000 environmental particles including 6841 TWP), and its application within a one-year monitoring campaign at two Swiss sites. In this study, the mass concentrations of TWP in the airborne fractions PM80-10, PM10-2.5 and PM2.5-1 were determined. Furthermore, the particle size distribution and shape characteristics of 5621 TWP were evaluated. A cut through a TWP by means of FIB-SEM evidences that the mineral and metal particles typically found in TWP are not only present on the particle surface but also throughout the complete TWP volume. At the urban background site, the annual average mass fraction of TWP and micro-rubber in PM10 was 1.8% (0.28 μg/m³) and 0.9%, respectively. At the urban kerbside site, the corresponding values were 6 times higher amounting to 10.5% (2.24 μg/m³) for TWP, and 5.0% for micro-rubber.

Green synthesis, characterization, antioxidant, antibacterial, and photocatalytic activity of Suaeda maritima (L.) Dumort aqueous extract-mediated copper oxide nanoparticles

Background

The aim of this work was to synthesize copper oxide nanoparticles (CuO NPs) utilizing heartwood aqueous extract of Suaeda maritima (L.) Dumort. The synthesis of CuO NPs using green methodology with small size and high stability paved the way to protect the environment by not involving toxic chemicals and environment-friendly methodology for pharmacological and photocatalytic applications. The aqueous areal parts extract of S. maritima (L.) Dumort was used for synthesis, characterization of CuO NPs was studied, and further its antioxidant, antibacterial, and photocatalytic activity for the removal of methylene blue was studied.

Results

The synthesized CuO NPs shows characteristic UV-visible absorption maximum at 282 nm. The FT-IR spectra shows peak at 3640 cm⁻¹ attributed to hydrogen bonded O-H group of poly phenols, alcohols, and N-H of amide. Strong peak at 1122 cm⁻¹ corresponds to C-OH stretch in phenols and alcohols. Peaks at 1467 cm⁻¹ and 1585 cm⁻¹ corresponds to C=C in aromatic compounds. Strong peak at 1749 cm⁻¹ represents the C=O in aldehydes or in keto compounds. Several strong bonds identified in the range of 1088 to 1225 cm⁻¹ representing C-O-C stretch vibrations. The synthesized particles were circular in shape with rough surface morphology and dispersed as clusters with size of 37 nm with metallic content of 73.8%. The synthesized CuO NPs were proved as potent antibacterial and antioxidant activities. The photocatalytic for the removal of methylene blue in aqueous solution was studied and results proved that the CuO NPs were effectively remove the dye up to 86.91% within less time of 75 min. Hence, the CuO NPs synthesized are high efficiency with less particle size and can be used as antioxidant, antibacterial agent, and also applicable for the removal of hazardous methylene blue dye from effluents and can contribute indirectly to clean up the environment.

Conclusions

The investigation reports the eco-friendly, cost-effective method for synthesizing copper oxide nanoparticles from S. maritima extract with biomedical applications.

Biological Nanofactories: Using Living Forms for Metal Nanoparticle Synthesis

Metal nanoparticles are nanosized entities with dimensions of 1-100 nm that are increasingly in demand due to applications in diverse fields like electronics, sensing, environmental remediation, oil recovery and drug delivery. Metal nanoparticles possess large surface energy and properties different from bulk materials due to their small size, large surface area with free dangling bonds and higher reactivity. High cost and pernicious effects associated with the chemical and physical methods of nanoparticle synthesis are gradually paving the way for biological methods due to their eco-friendly nature. Considering the vast potentiality of microbes and plants as sources, biological synthesis can serve as a green technique for the synthesis of nanoparticles as an alternative to conventional methods. A number of reviews are available on green synthesis of nanoparticles but few have focused on covering the entire biological agents in this process. Therefore present paper describes the use of various living organisms like bacteria, fungi, algae, bryophytes and tracheophytes in the biological synthesis of metal nanoparticles, the mechanisms involved and the advantages associated therein.

Non-exhaust traffic emissions: Sources, characterization, and mitigation measures

Non-exhaust emissions (NEE) of particulate matter (PM) from brake, tyre, road pavement and railway wear, as well as resuspension of already deposited road dust, account for up to 90% by mass of total traffic-related PM emitted. This review aims at analysing the current knowledge on road traffic NEE regarding sources, particle generation processes, chemical and physical characterization, and mitigation strategies. The literature on this matter often presents highly variable and hardly comparable results due to the heterogeneity of NEE sources and the absence of standardized sampling and measurement protocols. As evidence, emission factors (EFs) were found to range from 1 mg km^-1 veh^-1 to 18.5 mg km^-1 veh^-1 for brake wear, and from 0.3 mg km^-1 veh^-1 to 7.4 mg km^-1 veh^-1 for tyre wear. Resuspended dust, which varies in even wider ranges (from 5.4 mg km^-1 veh^-1 to 330 mg km^-1 veh^-1 for cars), is considered the prevailing NEE source. The lack of standardized monitoring approaches resulted in the impossibility of setting international regulations to limit NEE. Therefore, up until now the abatement of NEE has only been achieved by mitigation and prevention strategies. However, the effectiveness of these measures still needs to be improved and further investigated. As an example, mitigation strategies, such as street washing or sweeping, proved effective in reducing PM levels, but only in the short term. The replacement of internal combustion engines vehicles with electric ones was instead proposed as a prevention strategy, but there are still concerns regarding the increase of NEE deriving from the extra weight of the batteries. The data reported in this review highlighted the need for future studies to broaden their research area, and to focus not only on the standardization of methods and the introduction of regulations, but also on improving already existing technologies and mitigating strategies.

Antidiabetic and Hypolipidemic Potential of Green AgNPs against Diabetic Mice

Green nanotechnology-based approaches have been acquired as environmentally friendly and cost effective with many biomedical applications. The present study reports the synthesis of silver nanoparticles (AgNPs) from the leaves of Emblica phyllanthus, characterized by UV-Vis spectroscopy, EDX, SEM, AFM, and XRD. The acute and chronic antidiabetic and hypolipidemic potential of AgNPs was studied in alloxan-induced diabetic mice. A total of 11 groups (G1-G11, n = 6) of mice were treated with different concentrations (150 and 300 mM) and sizes of AgNPs and compared with those treated with standard glibenclamide. A significant decrease (P > 0.05) in the glucose level was achieved for 30, 45, and 65 nm after 15 days of treatment compared to the diabetic control. The oral administration of optimal AgNPs reduced the glucose level from 280.83 ± 4.17 to 151.17 ± 3.54 mg/dL, while the standard drug glibenclamide showed the reduction in glucose from 265.5 ± 1.43 to 192 ± 3.4 mg/dL. Histopathological studies were performed in dissected kidney and liver tissues of the treated mice, which revealed significant recovery in the liver and kidney after AgNP treatment. Acute toxicity study revealed that AgNPs were safe up to a size of 400 nm and the raw leaf extract of Emblica phyllanthus was safe up to 2500 mg/kg b.w. This study may help provide more effective and safe treatment options for diabetes compared to traditionally prescribed antidiabetic drugs.

Green synthesis, in vivo and in vitro pharmacological studies of Tamarindus indica based gold nanoparticles

The current investigation aims to synthesize gold nanoparticles (AuNPs) from aqueous extract of Tamarindus indica and to evaluate the in vitro anti-bacterial and in vivo sedative and anelgescic activities of crude extract as well as synthesized AuNPs. Several methods have been reported to synthesize AuNPs; however, most of them were not ecofriendly. In the present study, the green synthesis of AuNPs has been carried out. Using the green synthesis method, AuNPs of T. indica were synthesized at room temperature (25 °C) by mixing 5 mL of HAuCl₄ (1 mM) with 1 mL of T. indica seed extract solution. This extract solution was prepared by taking 5 gm dry seeds in 100 mL of double deionized water with continuous stirring for up to 24 h at 80 °C. The stability of AuNPs was confirmed with the help of relevant experimental techniques including ultraviolet-visible (UV/Vis) showing maximum absorbance at 535-540 nm, Fourier transform infrared showing a broad signal at 3464 cm^-1 which can be attributed to either amide or hydroxyl functionalities and atomic force microscopy analysis showed that the biomaterial surrounding AuNPs was agglomerated which proves the formation of discrete nanostructutres. These AuNPs have been evaluated for their antibacterial potential. The results revealed good antibacterial activity of the samples against. Klebsiella pneumonia, Bacillus subtilis and Staphylococcus epidermidis with 10-12 mm zone of inhibition range. The AuNPs were also found stable at high temperature, over a range of pH and in 1 mM salt solution. Moreover, the crude extract and respective AuNPs also exhibited interesting sedative and analgesic activities. Hence, we focused on phytochemicals-mediated synthesis of AuNPs considered as greatest attention in the treatment of anti-bacterial, analgesic, and sedative.

Green synthesis of cerium oxide nanoparticles using Acorus calamus extract and their antibiofilm activity against bacterial pathogens

The emergence of multidrug resistance in bacterial pathogens has increased drastically and it has become prevalent in clinical infections. In last few decades, there is a large gap in the discovery of new antibiotics with novel mode of action. The situation of antimicrobial resistance has become so alarming that if not action is taken, infectious diseases will become major cause of global mortality and morbidity by 2050. The growing interest of researchers in nanotechnology and their possible application in healthcare is being seen as a new hope in discovery of novel antimicrobial agents. Among various approaches employed for the nanoparticle synthesis, biological methods are considered more advantageous and environment friendly. Biofilms are considered as novel target for the development of new antimicrobial entities. In this study, cerium oxide nanoparticles (CeO₂ -NPs) were synthesized using Acorus calamus aqueous extract and tested for the antibiofilm activity both against Gram +ve and Gram -ve bacteria. The average size of synthesized CeO₂ -NPs was found to be 22.03 nm. The biofilms of the test bacteria were inhibited by more than 75% by the treatment with CeO₂ -NPs. The quantitative biofilm data were further verified by light microscopy, electron microscopy, and confocal microscopy. The confocal and electron microscopic analysis confirmed that treatment with CeO2-NPs reduced the development and colonization of the bacteria on solid support. Moreover, it was found that the colonization and biofilm development by test bacteria were fairly reduced on the glass surface. Moreover, a dose-dependent inhibition of preformed biofilms was also found. The exopolysaccharides (EPS) production by the test bacteria were substantially reduced by the supplementation of CeO₂ -NPs in culture media. The findings of this study highlight the efficacy of cerium oxide nanoparticles against bacterial pathogens that may be exploited for the development of new alternative antimicrobial agent.

Microwave-Assisted Rapid Green Synthesis of Gold Nanoparticles Using Seed Extract of Trachyspermum ammi: ROS Mediated Biofilm Inhibition and Anticancer Activity

Green synthesis of metal nanoparticles using plant extracts as capping and reducing agents for the biomedical applications has received considerable attention. Moreover, emergence and spread of multidrug resistance among bacterial pathogens has become a major health concern and lookout for novel alternative effective drugs has gained momentum. In current study, we synthesized gold nanoparticles using the seed extract of Trachyspermum ammi (TA-AuNPs), assessed its efficacy against drug resistant biofilms of Listeria monocytogenes and Serratia marcescens, and evaluated its anticancer potential against HepG2 cancer cell lines. Microwave-assisted green synthesis of gold nanoparticles was carried out and characterization was done using UV-vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and dynamic light scattering (DLS). Most nanoparticles were observed as spherical and spheroidal with few anisotropies with an average crystalline size of 16.63 nm. Synthesized TA-AuNPs demonstrated significant biofilm inhibitory activity against L. monocytogenes (73%) as well as S. marcescens (81%). Exopolysaccharide (EPS), motility, and CSH, key elements that facilitate the formation and maintenance of biofilm were also inhibited significantly at the tested sub-minimum inhibitory concentrations (sub-MICs). Further, TA-AuNPs effectively obliterated preformed mature biofilms of S. marcescens and L. monocytogenes by 64% and 58%, respectively. Induction of intracellular ROS production in TA-AuNPs treated bacterial cells could be the plausible mechanism for the reduced biofilm formation in test pathogens. Administration of TA-AuNPs resulted in the arrest of cellular proliferation in a concentration-dependent manner. TA-AuNPs decrease the intracellular GSH in HepG2 cancer cell lines, cells become more prone to ROS generation, hence induce apoptosis. Thus, this work proposes a new eco-friendly and rapid approach for fabricating NPs which can be exploited for multifarious biomedical applications.

Flower-Based Green Synthesis of Metallic Nanoparticles: Applications beyond Fragrance

Green synthesis has gained wide attention as a sustainable, reliable, and eco-friendly approach to the synthesis of a variety of nanomaterials, including hybrid materials, metal/metal oxide nanoparticles, and bioinspired materials. Plant flowers contain diverse secondary compounds, including pigments, volatile substances contributing to fragrance, and other phenolics that have a profound ethnobotanical relevance, particularly in relation to the curing of diseases by 'Pushpa Ayurveda' or floral therapy. These compounds can be utilized as potent reducing agents for the synthesis of a variety of metal/metal oxide nanoparticles (NPs), such as gold, silver, copper, zinc, iron, and cadmium. Phytochemicals from flowers can act both as reducing and stabilizing agents, besides having a role as precursor molecules for the formation of NPs. Furthermore, the synthesis is mostly performed at ambient room temperatures and is eco-friendly, as no toxic derivatives are formed. The NPs obtained exhibit unique and diverse properties, which can be harnessed for a variety of applications in different fields. This review reports the use of a variety of flower extracts for the green synthesis of several types of metallic nanoparticles and their applications. This review shows that flower extract was mainly used to design gold and silver nanoparticles, while other metals and metal oxides were less explored in relation to this synthesis. Flower-derived silver nanoparticles show good antibacterial, antioxidant, and insecticidal activities and can be used in different applications.

Primary Immunodeficiencies: Diseases of Children and Adults - A Review

Primary immunodeficiencies (PIDs) belong to a group of rare congenital diseases occurring all over the world that may be seen in both children and adults. In most cases, genetic predispositions are already known. As shown in this review, genetic abnormalities may be related to dysfunction of the immune system, which manifests itself as recurrent infections, increased risk of cancer, and autoimmune diseases. This article reviews the various forms of PIDs, including their characterization, management strategies, and complications. Novel aspects of the diagnostics and monitoring of PIDs are presented.

Comparison of Polydopamine-Coated Mesoporous Silica Nanorods and Spheres for the Delivery of Hydrophilic and Hydrophobic Anticancer Drugs

Mesoporous silica nanoparticles (MSNs) have been widely studied as drug delivery systems in nanomedicine. Surface coating of MSNs have enabled them to perform efficiently in terms of bioavailability, biocompatibility, therapeutic efficacy and targeting capability. Recent studies have suggested the use of polydopamine (PDA) as a facilitative coating for MSNs that provides sustained and pH-responsive drug release, owing to the adhesive "molecular-glue" function of PDA. This further endows these hybrid MSN@PDA particles with the ability to carry large amounts of hydrophilic drugs. In this study, we expand the feasibility of this platform in terms of exploring its ability to also deliver hydrophobic drugs, as well as investigate the effect of particle shape on intracellular delivery of both a hydrophilic and hydrophobic anticancer drug. MSN@PDA loaded with doxorubicin (hydrophilic) and fingolimod (hydrophobic) was studied via a systematic in vitro approach (cellular internalization, intracellular drug distribution and cytotoxicity). To promote the cellular uptake of the MSN@PDA particles, they were further coated with a polyethylene imine (PEI)-polyethylene glycol (PEG) copolymer. Drug-loaded, copolymer-coated MSN@PDA showed effective cellular uptake, intracellular release and an amplified cytotoxic effect with both doxorubicin and fingolimod. Additionally, rods exhibited delayed intracellular drug release and superior intracellular uptake compared to spheres. Hence, the study provides an example of how the choice and design of drug delivery systems can be tuned by the need for performance, and confirms the PDA coating of MSNs as a useful drug delivery platform beyond hydrophilic drugs.

Synthesis and biological function of Nickel and Copper nanoparticles

Nickel and Copper nanoparticles were synthesized by simple chemical method and studied for antimicrobial activities. The size of synthesized Nickel and Copper nanoparticles was found to be 24.00 nm and 13.13 nm respectively. The XRD analysis reveals the crystal system of Nickel and Copper nanoparticles. Copper nanoparticles were found orthorhombic whereas the nickel nanoparticles were monoclinic. The antimicrobial activities of Nickel and Copper nanoparticles dispersed in DMSO was investigated. Comparative sensitivity test of these synthesized nanoparticles was carried out against three pathogenic micro-organisms (Gram negative bacteria), viz. Escherichia coli, Klebsiella pneumoniae and Pneumonia Typhus, using agar diffusion cup plate method. Copper and Nickel nanoparticles have shown appreciable sensitivity at 100 μg/ml against all test micro-organisms. Comparatively, Copper nanoparticles were found to exhibit higher zone of inhibition (ZOI) than Nickel nanoparticles.

Production, characterization and antibacterial activity of silver nanoparticles produced by Fusarium oxysporum and monitoring of protein-ligand interaction through in-silico approaches

The present study envisages biological production of silver nanoparticles using Fusarium oxysporum and in-silico identification of the antibacterial activity of the nanoparticles using protein-ligand interaction studies. The morphology of the nanoparticles was variable, with majority of them spherical in the size range 1-50 nm. For in-silico studies, two microorganisms, Escherichia coli and Pseudomonas aeruginosa were selected and metal docking was carried out using the licensed software SYBYL X 1.1.1. The ligand docked deeply into the binding pockets of the outer membrane proteins (OMPs) of both E. coli and P. aeruginosa. The results showed that silver may prove to be a strong antibacterial agent against both the pathogens, with the antibacterial action of silver being greater in the case of P. aeruginosa. The results obtained through in-silico studies were further validated by in-vitro approaches on both solid and liquid media to confirm the results obtained by in-silico analysis. The corroboration of in-silico and in-vitro results amply demonstrates the immense antibacterial potential of silver nanoparticles against the selected pathogens.

Fibrous polymer nanomaterials for biomedical applications and their transport by fluids: an overview

Over the past few decades, there has been strong interest in the development of new micro- and nanomaterials for biomedical applications. Their use in the form of capsules, particles or filaments suspended in body fluids is associated with conformational changes and hydrodynamic interactions responsible for their transport. The dynamics of fibres or other long objects in Poiseuille flow is one of the fundamental problems in a variety of biomedical contexts, such as mobility of proteins, dynamics of DNA or other biological polymers, cell movement, tissue engineering, and drug delivery. In this review, we discuss several important applications of micro and nanoobjects in this field and try to understand the problems of their transport in flow resulting from material-environment interactions in typical, crowded, and complex biological fluids. Our aim is to elucidate the relationship between the nano- and microscopic structures of elongated polymer particles and their flow properties, thus opening the possibility to design nanoobjects that can be efficiently transported by body fluids for targeted drug release or local tissue regeneration.

Ultrasmall superparamagnetic Fe3O4 nanoparticles: honey-based green and facile synthesis and in vitro viability assay

Introduction

In the present research, we report a quick and green synthesis of magnetite nanoparticles (Fe₃O₄-NPs) in aqueous solution using ferric and ferrous chloride, with different percentages of natural honey (0.5%, 1.0%, 3.0% and 5.0% w/v) as the precursors, stabilizer, reducing and capping agent, respectively. The effect of the stabilizer on the magnetic properties and size of Fe₃O₄-NPs was also studied.

Methods

The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy.

Results

The XRD analysis indicated the presence of pure Fe₃O₄-NPs while the TEM images indicated that the Fe₃O₄-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM study demonstrated that the magnetic properties were enhanced with the decrease in the percentage of honey. In vitro viability evaluation of Fe₃O₄-NPs performed by using the MTT assay on the WEHI164 cells demonstrated no significant toxicity in higher concentration up to 140.0 ppm, which allows them to be used in some biological applications such as drug delivery.

Conclusion

The presented synthesis method can be used for the controlled synthesis of Fe₃O₄-NPs, which could be found to be important in applications in biotechnology, biosensor and biomedicine, magnetic resonance imaging and catalysis.

Augmentation of therapeutic potential of curcumin using nanotechnology: current perspectives

Curcumin, an active principle of Curcuma longa, is extracted from the rhizome. Its therapeutic efficiency has been proved using various in vitro and in vivo models. Inflammatory, neoplastic and preneoplastic diseases are the major targets using curcumin as therapeutic agent. Feasible clinical formulations could not be obtained because of its lack of solubility, stability and higher degradation rate. Recently, many techniques have been evolved to improve the physicochemical properties of pharmacological compounds, thereby increasing their biological activity. Curcumin has been developed using various techniques, particularly micro and nanotechnology to improve its stability and bioavailability. This review focuses on the studies pertaining to the delivery of curcumin in the form of micro and nanosize formulations for the treatment of a variety of diseases.

Phytofabricated gold nanoparticles and their biomedical applications

In a couple of decades, nanotechnology has become a trending technology owing to its integrated science collection that incorporates variety of fields such as chemistry, physics, medicine, catalytic processes, food processing industries, electronics and energy sectors. One of the emerging fields of nanotechnology that has gained momentous admiration is nano-biotechnology. Nano-biotechnology is an integrated combination of biology with nanotechnology that encompasses the tailoring, and synthesis of small particles that are less than 100nm in size and subsequent exploitation of these particles for their biological applications. Though the variety of physical techniques and chemical procedures are known for the nanoparticles synthesis, biological approach is considered to be the preferred one. Environmental hazards and concerns associated with the physical and chemical approaches of nanoparticles synthesis has added impetus and zenith to the biological approach involving the use of plants and microorganisms. The current review article is focused on the synthesis of plant-derived (phytochemical) gold nanoparticles alongside their scope in biomedical applications.

A Review of Current Research into the Biogenic Synthesis of Metal and Metal Oxide Nanoparticles via Marine Algae and Seagrasses

Today there is a growing need to develop reliable, sustainable, and ecofriendly protocols for manufacturing a wide range of metal and metal oxide nanoparticles. The biogenic synthesis of nanoparticles via nanobiotechnology based techniques has the potential to deliver clean manufacturing technologies. These new clean technologies can significantly reduce environmental contamination and decease the hazards to human health resulting from the use of toxic chemicals and solvents currently used in conventional industrial fabrication processes. The largely unexplored marine environment that covers approximately 70% of the earth’s surface is home to many naturally occurring and renewable marine plants. The present review summarizes current research into the biogenic synthesis of metal and metal oxide nanoparticles via marine algae (commonly known as seaweeds) and seagrasses. Both groups of marine plants contain a wide variety of biologically active compounds and secondary metabolites that enables these plants to act as biological factories for the manufacture of metal and metal oxide nanoparticles.

Sandwiches of N-doped diamondoids and benzenevialone pair–cation and cation–pi interaction: a DFT study

Cation–lone pair and cation–pi interactions in the complexes of N-doped dimondoids.

Punicalagin Green Functionalized Cu/Cu2O/ZnO/CuO Nanocomposite for Potential Electrochemical Transducer and Catalyst

A novel ternary Punica granatum L-Cu/Cu2O/CuO/ZnO nanocomposite was successfully synthesised via green route. In this work, we demonstrate that the green synthesis of metal oxides is more viable and facile compare to other methods, i.e., physical and chemical routes while presenting a potential electrode for energy applications. The prepared nanocomposite was characterised by both microscopic and spectroscopic techniques. High-resolution scanning electron microscopy (HRSEM) and X-ray diffraction (XRD) techniques revealed different transitional phases with an average nanocrystallite size of 29-20 mm. It was observed that the nanocomposites changed from amorphous-slightly crystalline Cu/Cu2O to polycrystalline Cu/Cu2O/CuO/ZnO at different calcination temperatures (room temperature-RT- 600 °C). The Cu/Cu2O/ZnO/CuO metal oxides proved to be highly crystalline and showed irregularly distributed particles with different sizes. Meanwhile, Fourier transform infrared (FTIR) spectroscopy confirmed the purity while together with ultraviolet-visible (UV-Vis) spectroscopy proved the proposed mechanism of the synthesised nanocomposite. UV-Vis showed improved catalytic activity of the prepared metal oxides, evident by narrow band gap energy. The redox and electrochemical properties of the prepared nanocomposite were achieved by cyclic voltammetry (CV), electrochemical impedance (EIS) and galvanostatic charge-discharge (GCD). The maximum specific capacitance (C s) was calculated to be 241 F g(-1) at 50 mV s(-1) for Cu/Cu2O/CuO/ZnO nanoplatelets structured electrode. Moreover, all the CuO nanostructures reveal better power performance, excellent rate as well as long term cycling stability. Such a study will encourages a new design for a wide spectrum of materials for smart electronic device applications.

Comparative in vivo toxicity assessment places multiwalled carbon nanotubes at a higher level than mesoporous silica nanoparticles

In the present work, we took two nanomaterials (NMs), mesoporous silica nanoparticles (MSNs) and multiwalled carbon nanotubes (MWCNTs), and compared their in vivo toxicity taking albino mice as a test animal model. Presently, conflicting data persist regarding behavior of these NMs with macromolecules like protein and lipid at the cellular level in cell lines as well as in animal models and this generated the interest to study them. The mice were treated orally with a single dose of 50 ppm MWCNTs and intraperitoneally with 10, 25, and 50 mg kg−1 body weight (BW) of MSNs and 1.5, 2.0, and 2.5 mg kg−1 BW of MWCNTs. Liver enzyme markers serum aspartate aminotransferase (AST), alanine aminotransferase, and alkaline phosphatase along with total protein (TP) levels were evaluated 7 days postexposure. No significant differences in organ weight indices or enzyme levels were observed between different treatment doses but there were significant differences between the treatment groups and the controls. Of the three enzymes assayed, AST displayed a peculiar pattern, especially in the MWCNTs intraperitoneally treated group. TP level was significantly increased in the orally treated MWCNTs group. The results showed that MWCNTs even at much smaller doses than MSNs displayed similar toxicity levels, suggesting that toxicity of MWCNTs is greater than MSNs.

Green synthesis of nanoparticles and its potential application

Nanotechnology is a new and emerging technology with wealth of applications. It involves the synthesis and application of materials having one of the dimensions in the range of 1-100 nm. A wide variety of physico-chemical approaches are being used these days for the synthesis of nanoparticles (NPs). However, biogenic reduction of metal precursors to produce corresponding NPs is eco-friendly, less expensive, free of chemical contaminants for medical and biological applications where purity of NPs is of major concern. Biogenic reduction is a "Bottom Up" approach similar to chemical reduction where a reducing agent is replaced by extract of a natural products with inherent stabilizing, growth terminating and capping properties. Furthermore, the nature of biological entities in different concentrations in combination with reducing organic agents influence the size and shape of NPs. Present review focuses on microbes or plants based green synthesis of Ag, Au, Cu, Fe, Pd, Ru, PbS, CdS, CuO, CeO2, Fe3O4, TiO2, and ZnO NPs and their potential applications.

Green Synthesis of Metallic Nanoparticles via Biological Entities

Nanotechnology is the creation, manipulation and use of materials at the nanometre size scale (1 to 100 nm). At this size scale there are significant differences in many material properties that are normally not seen in the same materials at larger scales. Although nanoscale materials can be produced using a variety of traditional physical and chemical processes, it is now possible to biologically synthesize materials via environment-friendly green chemistry based techniques. In recent years, the convergence between nanotechnology and biology has created the new field of nanobiotechnology that incorporates the use of biological entities such as actinomycetes algae, bacteria, fungi, viruses, yeasts, and plants in a number of biochemical and biophysical processes. The biological synthesis via nanobiotechnology processes have a significant potential to boost nanoparticles production without the use of harsh, toxic, and expensive chemicals commonly used in conventional physical and chemical processes. The aim of this review is to provide an overview of recent trends in synthesizing nanoparticles via biological entities and their potential applications.

Carbon Nanotropes: A Contemporary Paradigm in Drug Delivery

Discovery of fullerenes and other nanosized carbon allotropes has opened a vast new field of possibilities in nanotechnology and has become one of the most promising research areas. Carbon nanomaterials have drawn interest as carriers of biologically pertinent molecules due to their distinctive physical, chemical and physiological properties. We have assigned the nomenclature “Carbon Nanotropes” to the nanosized carbon allotropes. Carbon nanotropes such as fullerenes, carbon nanotubes (CNTs) and graphenes, have exhibited wide applicability in drug delivery, owing to their small size and biological activity. The nanotherapeutics/diagnostics will allow a deeper understanding of human ills including cancer, neurodegenerative diseases, genetic disorders and various other complications. Recently, nanomaterials with multiple functions, such as drug carrier, MRI, optical imaging, photothermal therapy, etc., have become more and more popular in the domain of cancer and other areas of research. This review is an endeavor to bring together the usefulness of the carbon nanomaterials in the field of drug delivery. The last section of the review encompasses the recent patents granted on carbon nanotropes at United State Patent Trademark Office (USPTO) in the related field.

Antinociceptive, muscle relaxant and sedative activities of gold nanoparticles generated by methanolic extract of Euphorbia milii

Background

Nanotechnology has potential future for enhancing therapeutic efficacy and reducing the unwanted effects of herbal drugs. The biological research on Euphorbia species has been supported by the use of some plants in traditional medicines. Many species of Euphorbia have been reported as having strong sedative and analgesic effects. In the present research work gold nanoparticles of Euphorbia milii methanolic extract (Au-EM) were synthesized, characterized and tested for antinociceptive, muscle relaxant and sedative activities.

Methods

Au-EM was prepared by stirring 1 mM warm trihydrated tetrachloroaurate solution with E. milii methanolic extract without using any external reducing agents. The gold nanoparticles were characterized by UV-Visible spectroscopy, infrared spectrophotometery, atomic force microscopy and scanning electron microscopy while their stability was evaluated against varying pH and different volumes of sodium chloride (NaCl). The metal sensing capacity of Au-EM was tested towards cobalt, copper, lead, mercury and nickel. Au-EM was evaluated in BALB/c mice at a dose of 10 and 20 mg/kg for antinociceptive, muscle relaxant and sedative activities in comparison with the crude E. milii methanolic extract.

Results

Au-EM showed remarkable stability in different NaCl and pH solutions. Au-EM produced significant (P < 0.01) antinociceptive effect at doses of 10 and 20 mg/kg as compared to the crude E. milii methanolic extract. In the rotarod test, Au-EM showed significant muscle relaxant effect at 10 mg/kg (P < 0.05) and 20 mg/kg (P < 0.01) after 30, 60 and 90 min. In an open field test significant sedative effect (P < 0.05) of Au-EM was observed at 10 and 20 mg/kg. Moreover significant detection sensitivity was demonstrated towards all the tested heavy metals.

Conclusions

These results concluded that the gold nanoparticles improved the potency of E. milii methanolic extract and exhibited significant analgesic, muscle relaxant and sedative properties. The significant metals sensing ability and enhanced stability in different NaCl and pH solutions may enable us to explore different formulations of E. milii gold nanoparticles for potentially effective and safe nano-herbal therapy.

Nanosized microporous crystals: emerging applications

This review highlights recent developments in the synthesis and unconventional applications of nanosized microporous crystals including framework (zeolites) and layered (clays) type materials. Owing to their microporous nature nanosized zeolites and clays exhibit novel properties, different from those of bulk materials. The factors controlling the formation of nanosized microporous crystals are first revised. The most promising approaches from the viewpoint of large-scale production of nanosized zeolites and clays are discussed in depth. The preparation and advanced applications of nanosized zeolites and clays in free (suspension and powder forms) and fixed (films) forms are summarized. Further the review emphasises the non-conventional applications of new porous materials. A comprehensive analysis of the emerging applications of microporous nanosized crystals in the field of semiconductor industry, optical materials, chemical sensors, medicine, cosmetics, and food industry is presented. Finally, the future needs and perspectives of nanosized microporous materials (zeolites and clays) are addressed.

Green Synthesis of Silver Nanoparticle Using Banana (Musa) Sap

Green synthesis of silver nanoparticles using banana sap as a solvent, reducing agent and capping agent is reported in this work. Banana sap has also been used as a binder to incorporate silver nanoparticles into cotton fabric. UV-Visible spectroscopy was used to monitor the quantitative formation of silver nanoparticles. Silver nanoparticle coated fabric showed high antimicrobial activity against gram negative bacteria such asPseudomonas aureginosaandEscherichia coli, and gram positive bacteria such asBacillus subtilisandStaphylococcus aureus.KeywordsGreen synthesis, Silver nanoparticles, banana sap, antimicrobial activity

Nanorobotic Applications in Medicine: Current Proposals and Designs

Advances in technology have increased our ability to manipulate the world around us on an ever-decreasing scale. Nanotechnologies are rapidly emerging within the realm of medicine, and this subfield has been termed nanomedicine. Use of nanoparticle technology has become familiar and increasingly commonplace, especially with pharmaceutical technology. An exciting and promising area of nanotechnological development is the building of nanorobots, which are devices with components manufactured on the nanoscale. This area of study is replete with potential applications, many of which are currently being researched and developed. The goal of this paper is to give an introduction to the emerging field of nanorobotics within medicine, and provide a review of the emerging applications of nanorobotics to fields ranging from neurosurgery to dentistry.

Overview of the role of nanotechnological innovations in the detection and treatment of solid tumors

Nanotechnology, although still in its infantile stages, has the potential to revolutionize the diagnosis, treatment, and monitoring of disease progression and success of therapy for numerous diseases and conditions, not least of which is cancer. As it is a leading cause of mortality worldwide, early cancer detection, as well as safe and efficacious therapeutic intervention, will be indispensable in improving the prognosis related to cancers and overall survival rate, as well as health-related quality of life of patients diagnosed with cancer. The development of a relatively new field of nanomedicine, which combines various domains and technologies including nanotechnology, medicine, biology, pharmacology, mathematics, physics, and chemistry, has yielded different approaches to addressing these challenges. Of particular relevance in cancer, nanosystems have shown appreciable success in the realm of diagnosis and treatment. Characteristics attributable to these systems on account of the nanoscale size range allow for individualization of therapy, passive targeting, the attachment of targeting moieties for more specific targeting, minimally invasive procedures, and real-time imaging and monitoring of in vivo processes. Furthermore, incorporation into nanosystems may have the potential to reintroduce into clinical practice drugs that are no longer used because of various shortfalls, as well as aid in the registration of new, potent drugs with suboptimal pharmacokinetic profiles. Research into the development of nanosystems for cancer diagnosis and therapy is thus a rapidly emerging and viable field of study.

Rapid green synthesis of silver nanoparticles from Chrysanthemum indicum L and its antibacterial and cytotoxic effects: an in vitro study

The present work reports a simple, cost-effective, and ecofriendly method for the synthesis of silver nanoparticles (AgNPs) using Chrysanthemum indicum and its antibacterial and cytotoxic effects. The formation of AgNPs was confirmed by color change, and it was further characterized by ultraviolet-visible spectroscopy (435 nm). The phytochemical screening of C. indicum revealed the presence of flavonoids, terpenoids, and glycosides, suggesting that these compounds act as reducing and stabilizing agents. The crystalline nature of the synthesized particles was confirmed by X-ray diffraction, as they exhibited face-centered cubic symmetry. The size and morphology of the particles were characterized by transmission electron microscopy, which showed spherical shapes and sizes that ranged between 37.71-71.99 nm. Energy-dispersive X-ray spectroscopy documented the presence of silver. The antimicrobial effect of the synthesized AgNPs revealed a significant effect against the bacteria Klebsiella pneumonia, Escherichia coli, and Pseudomonas aeruginosa. Additionally, cytotoxic assays showed no toxicity of AgNPs toward 3T3 mouse embryo fibroblast cells (25 μg/mL); hence, these particles were safe to use.

A prospective overview of the essential requirements in molecular modeling for nanomedicine design

Nanotechnology has presented many new challenges and opportunities in the area of nanomedicine design. The issues related to nanoconjugation, nanosystem-mediated targeted drug delivery, transitional stability of nanovehicles, the integrity of drug transport, drug-delivery mechanisms and chemical structural design require a pre-estimated and determined course of assumptive actions with property and characteristic estimations for optimal nanomedicine design. Molecular modeling in nanomedicine encompasses these pre-estimations and predictions of pertinent design data via interactive computographic software. Recently, an increasing amount of research has been reported where specialized software is being developed and employed in an attempt to bridge the gap between drug discovery, materials science and biology. This review provides an assimilative and concise incursion into the current and future strategies of molecular-modeling applications in nanomedicine design and aims to describe the utilization of molecular models and theoretical-chemistry computographic techniques for expansive nanomedicine design and development.

Carbon nanomaterials for nerve tissue stimulation and regeneration

Nanotechnology offers new perspectives in the field of innovative medicine, especially for reparation and regeneration of irreversibly damaged or diseased nerve tissues due to lack of effective self-repair mechanisms in the peripheral and central nervous systems (PNS and CNS, respectively) of the human body. Carbon nanomaterials, due to their unique physical, chemical and biological properties, are currently considered as promising candidates for applications in regenerative medicine. This chapter discusses the potential applications of various carbon nanomaterials including carbon nanotubes, nanofibers and graphene for regeneration and stimulation of nerve tissue, as well as in drug delivery systems for nerve disease therapy.

Theory, fabrication and applications of microfluidic and nanofluidic biosensors

Biosensors are a broad array of devices that detect the type and amount of a biological species or biomolecule. Several different types of biosensors have been developed that rely on changes to mechanical, chemical or electrical properties of the transduction or sensing element to induce a measurable signal. Often, a biosensor will integrate several functions or unit operations such as sample extraction, manipulation and detection on a single platform. This review begins with an overview of the current state-of-the-art biosensor field. Next, the review delves into a special class of biosensors that rely on microfluidics and nanofluidics by presenting the underlying theory, fabrication and several examples and applications of microfluidic and nanofluidic sensors.

Imaging the uptake of gold nanoshells in live cells using plasmon resonance enhanced four wave mixing microscopy

Gold nanoshells (GNS) are novel metal nanoparticles exhibiting attractive optical properties which make them highly suitable for biophotonics applications. We present a novel investigation using plasmon-enhanced four wave mixing microscopy combined with coherent anti-Stokes Raman scattering (CARS) microscopy to visualize the distribution of 75 nm radius GNS within live cells. During a laser tolerance study we found that cells containing nanoshells could be exposed to < 2.5 mJ each with no photo-thermally induced necrosis detected, while cell death was linearly proportional to the power over this threshold. The majority of the GNS signal detected was from plasmon-enhanced four wave mixing (FWM) that we detected in the epi-direction with the incident lasers tuned to the silent region of the Raman spectrum. The cellular GNS distribution was visualized by combining the epi-detected signal with forwards-detected CARS at the CH2 resonance. The applicability of this technique to real-world nanoparticle dosing problems was demonstrated in a study of the effect of H2S on nanoshell uptake using two donor molecules, NaHS and GYY4137. As GYY4137 concentration was increased from 10 µM to 1 mM, the nanoshell pixel percentage as a function of cell volume (PPCV) increased from 2.15% to 3.77%. As NaHS concentration was increased over the same range, the nanoshell PPCV decreased from 12.67% to 11.47%. The most important factor affecting uptake in this study was found to be the rate of H2S release, with rapid-release from NaHS resulting in significantly greater uptake.

Nanocompounds of iron and zinc: their potential in nutrition

Recent studies suggest nanostructured oxides and phosphates of Fe and atomically mixed Fe/Zn may be useful for nutritional applications. These compounds may have several advantages over existing fortificants, such as ferrous sulfate (FeSO(4)), NaFeEDTA and electrolytic iron. Because of their very low solubility and formation of soft agglomerates of micron size at neutral pH as well as their light native color, they tend to be less reactive in difficult-to-fortify foods and thus have superior sensory performance. At gastric pH the soft agglomerates break up and the Fe compounds rapidly and completely dissolve due to their very high surface area. This results in in vitro solubility and in vivo bioavailability comparable to FeSO(4). Doping with Mg and/or Ca may increase solubility and improve sensory characteristics by lightening color. Feeding the nanostructured compounds at 150-400 µg Fe day(-1) for 15 days to weanling rats in two studies did not induce measurable histological or biochemical adverse effects. No significant Fe was detected in the submucosa of the gastrointestinal tract or lymphatic tissues, suggesting that the nanosized Fe is absorbed through usual non-heme Fe absorption pathways. Thus, these novel compounds show promise as food fortificants or supplements.