Introduction to metallic nanoparticles

Green synthesis of silver nanoparticles using Omani pomegranate peel extract and two polyphenolic natural products: characterization and comparison of their antioxidant, antibacterial, and cytotoxic activities

Background

Green synthesis of silver nanoparticles (AgNPs) has gained popularity due to the economical and eco-friendly approach associated with it. The aim of the study was to biosynthesize silver nanoparticles using pomegranate peel extract (PPE), quercetin (Q), and gallic acid (GA) and to evaluate their antioxidant, antimicrobial, and cytotoxic activities.

Results

A sharp color change from yellow to brown, appearance of a peak in a UV spectrum around 413–425 nm, and four intense peaks in XRD spectra matching with the reference silver crystal confirmed the formation of AgNPs. SEM and TEM analysis revealed particles to be mostly spherical with few aggregates. Average particle size distribution and zeta potential was found to be 43.6 nm and −18.01mV, 31.6 nm and −21.5 mV, and 21.7 nm and −27.9 mV for Q-AgNPs, P-AgNPs, and GA-AgNPs, respectively. P-AgNPs showed excellent in vitro antioxidant activity (84.85–89.20%) and cytotoxic activity (100% mortality). P-AgNPs and GA-AgNPs exhibited good antimicrobial activity against the four bacterial strains comparable to the reference antibiotics but Q-AgNPs failed to inhibit the growth of P. vulgaris.

Conclusions

Omani pomegranate peel extract seems to be a potential and alternative source for the simple, one pot, eco-friendly green synthesis of extracellular stable AgNPs. The synthesized nanoparticles have the potential to be developed as possible antimicrobial agents and antioxidants.

Graphical abstract

Nanotechnology approaches for delivery and targeting of Amphotericin B in fungal and parasitic diseases

Amphotericin B (AMB), with widespread antifungal and anti-parasitic activities and low cross-resistance with other drugs, has long been identified as a potent antimicrobial drug. However, its clinical toxicities, especially nephrotoxicity, have limited its use in clinical practice. Lately, nano-based systems have been the subject of serious research and becoming an effective strategy to improve toxicity and antimicrobial potency. Commercial AMB lipid formulations have been developed in order to improve the therapeutic index and nephrotoxicity, while limited use is mainly due to their high cost. The review aimed to highlight the updated information on nanotechnology-based approaches to the development of AMB delivery and targeting systems for treatment of fungal diseases and leishmaniasis, regarding therapeutic challenges and achievements of various delivery systems.

Emerging Concern for Silver Nanoparticle Resistance in Acinetobacter baumannii and Other Bacteria

The misuse of antibiotics combined with a lack of newly developed ones is the main contributors to the current antibiotic resistance crisis. There is a dire need for new and alternative antibacterial options and nanotechnology could be a solution. Metal-based nanoparticles, particularly silver nanoparticles (NAg), have garnered widespread popularity due to their unique physicochemical properties and broad-spectrum antibacterial activity. Consequently, NAg has seen extensive incorporation in many types of products across the healthcare and consumer market. Despite clear evidence of the strong antibacterial efficacy of NAg, studies have raised concerns over the development of silver-resistant bacteria. Resistance to cationic silver (Ag+) has been recognised for many years, but it has recently been found that bacterial resistance to NAg is also possible. It is also understood that exposure of bacteria to toxic heavy metals like silver can induce the emergence of antibiotic resistance through the process of co-selection. Acinetobacter baumannii is a Gram-negative coccobacillus and opportunistic nosocomial bacterial pathogen. It was recently listed as the "number one" critical level priority pathogen because of the significant rise of antibiotic resistance in this species. NAg has proven bactericidal activity towards A. baumannii, even against strains that display multi-drug resistance. However, despite ample evidence of heavy metal (including silver; Ag+) resistance in this bacterium, combined with reports of heavy metal-driven co-selection of antibiotic resistance, little research has been dedicated to assessing the potential for NAg resistance development in A. baumannii. This is worrisome, as the increasingly indiscriminate use of NAg could promote the development of silver resistance in this species, like what has occurred with antibiotics.

Effect of gold nanoparticle treated dorsal root ganglion cells on peripheral neurite differentiation

The use of gold nanoparticles (AuNps) in applications connected to the peripheral nervous system (PNS) holds much promise in terms of therapeutic and diagnostic strategies. Despite their extensive use, a clear understanding of their effects on neurons and glia in the PNS is lacking. In this study, we set out to examine the effects of AuNps on dorsal root ganglion (DRG) cells, and how such AuNp-exposed cells could in-turn affect neurite differentiation. DRG cultures were exposed to mono-dispersed spherical-shaped AuNps of diameter 24.3 ± 2.3, 109.2 ± 14.7 or 175 ± 19.2 nm at varying concentrations. Cellular uptake and viability were quantified using flow-cytometry. Neurite differentiation was quantified using neurite tracing analysis in PC-12 and DRG neurons exposed to conditioned media derived from AuNp-treated DRG cells. Both neurons and glia were found to internalize AuNps. DRG cell viability was significantly reduced upon treatment with higher concentration of 175 nm sized AuNps, while 24 nm and 109 nm sized AuNps had no effect. Further, conditioned media from AuNp-treated DRG cells produced comparable neurite outgrowth and neurite branching measurement as controls in PC-12 and DRG neurons. DRG cells were quite resilient to AuNp exposure in mild-moderate concentration. AuNp-exposed DRG cells, irrespective of size and concentration range tested, did not affect neuronal differentiation.

Metallic nanoparticles as drug delivery system for the treatment of cancer

INTRODUCTION

The targeted delivery of anticancer agents to tumor is a major challenge because most of the drugs show off-target effect resulting in nonspecific cell death. Multifunctionalized metallic nanoparticles (NPs) are explored as new carrier system in the era of cancer therapeutics. Researchers investigated the potential of metallic NPs to target tumor cells by active and passive mechanisms, thereby reducing off-target effects of anticancer agents. Moreover, photocatalytic activity of upconversion nanoparticles (UCNPs) and the enhanced permeation and retention (EPR) effect have also gained wide potential in cancer treatment. Recent advancement in the field of nanotechnology highlights their potency for cancer therapy.

AREAS COVERED

This review summarizes the types of gold and silver metallic NPs with targeting mechanisms and their potentiality in cancer therapy.

EXPERT OPINION

Recent advances in the field of nanotechnology for cancer therapy offer high specificity and targeting efficiency. Targeting tumor cells through mechanistic pathways using metallic NPs for the disruption/alteration of molecular profile and survival rate of the tumor cells has led to an effective approach for cancer therapeutics. This alteration in the survival rate of the tumor cells might decrease the proliferation thereby resulting in more efficient management in the treatment of cancer.

Development of a Structural Comparison Method to Promote Exploration of the Potential Energy Surface in the Global Optimization of Nanoclusters

A structural comparison method (SCM) was created to quantify the structural diversity of nanoclusters and was implemented into a global optimization algorithm to evaluate structural diversity between generated clusters on the fly and promote exploration of the potential energy surface. The SCM evaluated topological differences between clusters using the common neighbor analysis and provided a numerical measure of similarity between the two clusters. The SCM was implemented into a genetic algorithm by integrating it into a new structure + energy fitness operator such that structural diversity of clusters in the population and their energies were used to assign fitness values to clusters. The efficiency of the genetic algorithm with this new fitness operator was benchmarked against several Lennard-Jones clusters (LJ₃₈, LJ₇₅, and LJ₉₈) known to be difficult cases for global optimization algorithms. For LJ₃₈ and LJ₇₅, this new structure + energy fitness operator performed equally well or better than the energy fitness operator. However, the efficiency of locating the global minimum of LJ₉₈ decreased using this new structure + energy fitness operator. Further analysis of the genetic algorithm with this fitness operator showed that the algorithm did indeed promote exploration of the PES of LJ₉₈ as desired but hindered refinement of clusters, preventing it from locating the global minimum even if the energy funnel of the global minimum had been located.

Simple Equations Pertaining to the Particle Number and Surface Area of Metallic, Polymeric, Lipidic and Vesicular Nanocarriers

Introduction: Bioactive encapsulation and drug delivery systems have already found their way to the market as efficient therapeutics to combat infections, viral diseases and different types of cancer. The fields of food fortification, nutraceutical supplementation and cosmeceuticals have also been getting the benefit of encapsulation technologies. Aim: Successful formulation of such therapeutic and nutraceutical compounds requires thorough analysis and assessment of certain characteristics including particle number and surface area without the need to employ sophisticated analytical techniques. Solution: Here we present simple mathematical formulas and equations used in the research and development of drug delivery and controlled release systems employed for bioactive encapsulation and targeting the sites of infection and cancer in vitro and in vivo. Systems covered in this entry include lipidic vesicles, polymeric capsules, metallic particles as well as surfactant- and tocopherol-based micro- and nanocarriers.

Magnetic Properties of Fe, Co and Ni Based Nanopowders Produced by Chemical-Metallurgy Method

This research study describes the magnetic properties of Fe, Co and Ni metallic nanopowders (NPs) and their ternary nanocomposites (NCs), which can be used as fillers in radio-wave absorbing composite materials and coatings, as well as for magnetic protection of banknotes and security paper. The nanopowders were prepared by the chemical metallurgy method. The desired properties of Fe, Co and Ni NPs and NCs were achieved by co-precipitation, the addition of surfactants and changes in reduction temperature and time parameters. Magnetic measurements showed that all samples of pure metal NPs are semi-hard magnetic materials. The added surfactants have distinct effects on the dimensional and magnetic characteristics of Fe, Co and Ni NPs. Ni–Co–Fe NCs are also mainly semi-hard magnetic materials. Fine-tuning of their composition and chemical reduction temperatures allows controlling the values of Ms and Hc in large ranges from 49 to 197 A·m2/kg and from 4.7 to 60.6 kA/m, respectively.

Plasmonic Nanoparticles as Optical Sensing Probes for the Detection of Alzheimer's Disease

Alzheimer's disease (AD), considered a common type of dementia, is mainly characterized by a progressive loss of memory and cognitive functions. Although its cause is multifactorial, it has been associated with the accumulation of toxic aggregates of the amyloid-β peptide (Aβ) and neurofibrillary tangles (NFTs) of tau protein. At present, the development of highly sensitive, high cost-effective, and non-invasive diagnostic tools for AD remains a challenge. In the last decades, nanomaterials have emerged as an interesting and useful tool in nanomedicine for diagnostics and therapy. In particular, plasmonic nanoparticles are well-known to display unique optical properties derived from their localized surface plasmon resonance (LSPR), allowing their use as transducers in various sensing configurations and enhancing detection sensitivity. Herein, this review focuses on current advances in in vitro sensing techniques such as Surface-enhanced Raman scattering (SERS), Surface-enhanced fluorescence (SEF), colorimetric, and LSPR using plasmonic nanoparticles for improving the sensitivity in the detection of main biomarkers related to AD in body fluids. Additionally, we refer to the use of plasmonic nanoparticles for in vivo imaging studies in AD.

Nanocarrier-delivered small interfering RNA for chemoresistant ovarian cancer therapy

Ovarian cancer is the fifth leading cause of cancer-related death in women in the United States. Because success in early screening is limited, and most patients with advanced disease develop resistance to multiple treatment modalities, the overall prognosis of ovarian cancer is poor. Despite the revolutionary role of surgery and chemotherapy in curing ovarian cancer, recurrence remains a major challenge in treatment. Thus, improving our understanding of the pathogenesis of ovarian cancer is essential for developing more effective treatments. In this review, we analyze the underlying molecular mechanisms leading to chemotherapy resistance. We discuss the clinical benefits and potential challenges of using nanocarrier-delivered small interfering RNA to treat chemotherapy-resistant ovarian cancer. We aim to elicit collaborative studies on nanocarrier-delivered small interfering RNA to improve the long-term survival rate and quality of life of patients with ovarian cancer. This article is categorized under: RNA Methods > RNA Nanotechnology Regulatory RNAs/RNAi/Riboswitches > RNAi: Mechanisms of Action.

The Use of Montmorillonite (MMT) in Food Nanocomposites: Methods of Incorporation, Characterization of MMT/Polymer Nanocomposites and Main Consequences in the Properties

BACKGROUND

The clay Montmorillonite (MMT) is among the nanofillers more frequently used in food packaging. The uniform dispersion of nanoparticles in polymers confers considerable improvement of mechanical, thermal, optical, and/or barrier properties in polymer/clay nanocomposites.

OBJECTIVE

The aim is to ascertain the state of the art of the use of MMT for packaging purposes, with special emphasis on food applications.

METHODS

A literature review was carried out through recent papers and patents that focused on the incorporation of MMT in polymers.

RESULTS

This review emphasizes the interaction of MMT with polymers and their levels of incorporation in the nanocomposites. This work also highlights the analytical methodologies used for the characterization of the polymer/clay nanocomposites and the main consequences of the fillers in the properties of nanocomposites. Challenges remain about increasing the compatibility between clays and biopolymers to promote their utilization in food packaging. New strategies for immobilization of oxides, enzymes, essential oils, and other bioactive compounds are needed.

CONCLUSION

MMT-based composite materials are promising to be used in intelligent and active packaging.

The Evaluation of Drug Delivery Nanocarrier Development and Pharmacological Briefing for Metabolic-Associated Fatty Liver Disease (MAFLD): An Update

Current research indicates that the next silent epidemic will be linked to chronic liver diseases, specifically non-alcoholic fatty liver disease (NAFLD), which was renamed as metabolic-associated fatty liver disease (MAFLD) in 2020. Globally, MAFLD mortality is on the rise. The etiology of MAFLD is multifactorial and still incompletely understood, but includes the accumulation of intrahepatic lipids, alterations in energy metabolism, insulin resistance, and inflammatory processes. The available MAFLD treatment, therefore, relies on improving the patient's lifestyle and multidisciplinary pharmacotherapeutic options, whereas the option of surgery is useless without managing the comorbidities of the MAFLD. Nanotechnology is an emerging approach addressing MAFLD, where nanoformulations are suggested to improve the safety and physicochemical properties of conventional drugs/herbal medicines, physical, chemical, and physiological stability, and liver-targeting properties. A wide variety of liver nanosystems were constructed and delivered to the liver, only those that addressed the MAFLD were discussed in this review in terms of the nanocarrier classes, particle size, shape, zeta potential and offered dissolution rate(s), the suitable preparation method(s), excipients (with synergistic effects), and the suitable drug/compound for loading. The advantages and challenges of each nanocarrier and the focus on potential promising perspectives in the production of MAFLD nanomedicine were also highlighted.

Nanoencapsulation of Plant Volatile Organic Compounds to Improve Their Biological Activities

Plant volatile organic compounds (volatiles) are secondary plant metabolites that play crucial roles in the reproduction, defence, and interactions with other vegetation. They have been shown to exhibit a broad range of biological properties and have been investigated for antimicrobial and anticancer activities. In addition, they are thought be more environmentally friendly than many other synthetic chemicals 1. Despite these facts, their applications in the medical, food, and agricultural fields are considerably restricted due to their volatilities, instabilities, and aqueous insolubilities. Nanoparticle encapsulation of plant volatile organic compounds is regarded as one of the best strategies that could lead to the enhancement of the bioavailability and biological activity of the volatile compounds by overcoming their physical limitations and promoting their controlled release and cellular absorption. In this review, we will discuss the biosynthesis and analysis of plant volatile organic compounds, their biological activities, and limitations. Furthermore, different types of nanoparticle platforms used to encapsulate the volatiles and the biological efficacies of nanoencapsulated volatile organic compounds will be covered.

Therapeutic Potential of Green Synthesized Metallic Nanoparticles against Staphylococcus aureus

BACKGROUND

The recent treatment challenges posed by the widespread emergence of pathogenic Multidrug-Resistant (MDR) bacterial strains are a cause of huge health troubles worldwide. Infections caused by MDR organisms are associated with longer period of hospitalization, increased mortality, and inflated healthcare costs. Staphylococcus aureus is one of these MDR organisms identified as an urgent threat to human health by the World Health Organization. Infections caused by S. aureus may range from simple cutaneous infestations to life threatening bacteremia. S. aureus infections get easily escalated in severely ill, hospitalized and or immunocompromised patients with incapacitated immune system. Also, in HIV-positive patients S. aureus ranks amongst one of the most common comorbidities where it can further worsen a patient's health condition. At present anti-staphylococcal therapy is reliant typically on chemotherapeutics that are gathering resistance and pose unfavorable side-effects. Thus, newer drugs are required that can bridge these shortcomings and aid effective control against S. aureus.

OBJECTIVE

In this review, we summarize drug resistance exhibited by S. aureus and lacunae in current anti-staphylococcal therapy, nanoparticles as an alternative therapeutic modality. The focus lays on various green synthesized nanoparticles, their mode of action and application as potent antibacterial compounds against S. aureus.

CONCLUSION

Use of nanoparticles as anti-bacterial drugs has gained momentum in recent past and green synthesized nanoparticles, which involves microorganisms and plants or their byproducts for synthesis of nanoparticles offer a potent, as well as environment friendly solution in warfare against MDR bacte.

Nano Metal based Herbal theranostics for Cancer management: coalescing nature's boon with nanotechnological advancement

Cancer is amongst the leading public health problems globally with continuously increasing prevalence rate that demands for extensive and expensive treatment. Despite availability of number of potential cancer therapies, inadequate success has been achieved due to complexity and heterogeneity of tumors. Moreover, late/ terminal stage cancer leads to multidrug resistance, excruciating side effects, recurrence, etc. This is because of low penetrability and deleterious effects of drug on non-target cells/ tissues. This requires for cost effective, efficacious, alternative/ adjunct, complementary medicines with targeted drug delivery approach. A potential strategy to resolve this difficulty is to use theranostics i.e., formulations having both a therapeutic element and an imaging agent. Phytotherapeutics have been extensively used since times immemorial, having wide acceptability, easy availability, minimal side effects and comparatively inexpensive. These herbal formulations are mostly orally administered and thus subjected to adverse pH, enzymatic degradation, poor gut absorption, low bioavailability and non-targeted delivery that ultimately lead to their poor effectiveness. Constraints associated with conventional phyto-pharmaceuticals can be improved by designing and using "Nano Delivery Systems" (NDS). The foremost aim of metal based NDS is to provide sustained drug release, site-specific action, improved patient's compliance and enhanced efficacy. Metal Nanocarriers carrying herbal drugs will avoid these obstructions, so the drug can circulate into the blood for a longer period of time and provide optimal amount of the drug to the site of action. Besides, Herbal drugs with NDS thus would be efficacious as alternative/ complementary cancer theranostics. Present review describes about novel theranostic systems employing metal nanocarriers with diagnostic and therapeutic properties as are an effective strategy for cancer treatment. These systems when conjugated with herbal drugs provide an efficient management strategy for cancer.

CS/Au/MWCNT nanohybrid as an efficient carrier for the sustained release of 5-FU and a study of its cytotoxicity on MCF-7

The chemical reduction method has been used to adeptly synthesize a CS/Au/MWCNT nanocomposite, to be used as a carrier for the effectual delivery of the anticancer drug 5-Fluorouracil. The work aims at utilizing the less investigated ternary nanocomposite system containing chitosan (CS), gold (Au) and MWCNT's to attain higher encapsulation efficiency and to enable a more sustained and prolonged release of 5-FU. This system has improved cytotoxicity when compared to the CS/Au binary system. The prepared sample has been characterized using various techniques that confirm the formation of the nanocomposite, encapsulation of 5-FU into the nanocomposite, the structure of 5-FU and Au in the nanocomposite and the formation of the polymer matrix nanocomposite. An increase in the encapsulation efficiency to 98% and loading efficiency to 43% is observed when compared to the binary composite, elucidating the importance of incorporation of carbon nanotubes into the nanocomposite. A reduction in the release percentage of 5-FU by 40% indicates a more prolonged release, which will enable a reduction of the number of dosages that need to be administered. This in turn leads to a reduction in the side effects posed by the drug 5-FU. Moreover, the effectiveness of the drug loaded nanocomposite system towards the inhibition of breast cancer cells, apparent from the attainment of 50% cell viability while taking sample concentrations as low as 25 μg ml-1, makes this ternary nanocomposite superior and significant.

A method based on asymmetric flow field flow fractionation hyphenated to inductively coupled plasma mass spectrometry for the monitoring of platinum nanoparticles in water samples

An analytical methodology based on asymmetric flow field flow fractionation hyphenated to inductively coupled plasma mass spectrometry (AF4-ICP-MS) has been developed for monitoring citrate coated platinum nanoparticles (PtNPs) of different sizes (5, 30, and 50 nm) in water samples. Several factors have been optimized, such as carrier composition, AF4 separation program, focusing step or cross flow values. Under the optimum conditions, PtNPs can be fractionated in about 30 min in a single run with quantitative recoveries of the membrane (100 ± 7%, n = 5). The optimized method has been successfully applied to study transformations, not only in size but also surface modifications, of PtNPs in synthetic and natural water samples over time. The effect of organic matter was specifically studied, and it was found to be a critical parameter. The analytical strategy followed in this work can be very useful to develop further environmental studies involving PtNPs.

Accumulation and cellular toxicity of engineered metallic nanoparticle in freshwater microalgae: Current status and future challenges

Metal nanoparticles (MNPs) are employed in a variety of medical and non-medical applications. Over the past two decades, there has been substantial research on the impact of metallic nanoparticles on algae and cyanobacteria, which are at the base of aquatic food webs. In this review, the current status of our understanding of mechanisms of uptake and toxicity of MNPs and metal ions released from MNPs after dissolution in the surrounding environment were discussed. Also, the trophic transfer of MNPs in aquatic food webs was analyzed in this review. Approximately all metallic nanoparticles cause toxicity in algae. Predominantly, MNPs are less toxic compared to their corresponding metal ions. There is a sufficient evidence for the trophic transfer of MNPs in aquatic food webs. Internalization of MNPs is indisputable in algae, however, mechanisms of their transmembrane transport are inadequately known. Most of the toxicity studies are carried out with solitary species of MNPs under laboratory conditions rarely found in natural ecosystems. Oxidative stress is the primary toxicity mechanism of MNPs, however, oxidative stress seems a general response predictable to other abiotic stresses. MNP-specific toxicity in an algal cell is yet unknown. Lastly, the mechanism of MNP internalization, toxicity, and excretion in algae needs to be understood carefully for the risk assessment of MNPs to aquatic biota.

External and Internal Stimuli-Responsive Metallic Nanotherapeutics for Enhanced Anticancer Therapy

Therapeutic, diagnostic, and imaging approaches based on nanotechnology offer distinct advantages in cancer treatment. Various nanotherapeutics have been presented as potential alternatives to traditional anticancer therapies such as chemotherapy, radiotherapy, and surgical intervention. Notably, the advantage of nanotherapeutics is mainly attributable to their accumulation and targeting ability toward cancer cells, multiple drug-carrying abilities, combined therapies, and imaging approaches. To date, numerous nanoparticle formulations have been developed for anticancer therapy and among them, metallic nanotherapeutics reportedly demonstrate promising cancer therapeutic and diagnostic efficiencies owing to their dense surface functionalization ability, uniform size distribution, and shape-dependent optical responses, easy and cost-effective synthesis procedure, and multiple anti-cancer effects. Metallic nanotherapeutics can remodel the tumor microenvironment by changing unfavorable therapeutic conditions into therapeutically accessible ones with the help of different stimuli, including light, heat, ultrasound, an alternative magnetic field, redox, and reactive oxygen species. The combination of metallic nanotherapeutics with both external and internal stimuli can be used to trigger the on-demand release of therapeutic molecules, augmenting the therapeutic efficacies of anticancer therapies such as photothermal therapy, photodynamic therapy, magnetic hyperthermia, sonodynamic therapy, chemodynamic therapy, and immunotherapy. In this review, we have summarized the role of different metallic nanotherapeutics in anti-cancer therapy, as well as their combinational effects with multiple stimuli for enhanced anticancer therapy.

Biogenic synthesis of Pd-nanoparticles using Areca Nut Husk Extract: a greener approach to access α-keto imides and stilbenes

An eco-friendly green method for a one-step synthesis of palladium nanoparticles and their synthetic utility are reported.

Phyto-drug conjugated nanomaterials enhance apoptotic activity in cancer

Cancer continues to be one of the leading causes of death worldwide and is a major obstacle to increased life expectancy. However, survival has not improved significantly with average cancer standard treatment strategies over the past few decades; survival rates have remained low, with tumor metastasis, adverse drug reactions, and drug resistance. Therefore, substitute therapies are essential to treat this dreadful disease. Recently, research has shown that natural compounds in plants, such as phytochemicals, are extensively exploited for their anticarcinogenic potential. Phytochemicals may show their anticancer activity different cancer cell markers may alter molecular pathways, which promote in cellular events such as cell cycle arrest and apoptosis, regulate antioxidant status, cell proliferation, migration, invasion and toxicity. Although their outstanding anticancer activity, however, their pharmacological budding is hindered by their low aqueous solubility, poor bioavailability, and poor penetration into cells, hepatic disposition, narrow therapeutic index, and rapid uptake by normal tissues. In this situation, nanotechnology has developed novel inventions to increase the potential use of phytochemicals in anticancer therapy. Nanoparticles can improve the solubility and stability of phytochemicals, specific tumor cell/tissue targeting, enhanced cellular uptake, reduction of phytochemicals. Therapeutic doses of phytochemicals for a long time. Additional benefits include better blood stability, multifunctional design of nanocarriers and improvement in countermeasures. This review summarizes the advances in the use of nanoparticles for the treatment of cancer, as well as various nano-drug deliveries of phytochemicals against cancer. In particular, we are introducing several applications of nanoparticles in combination with phyto-drug for the treatment of cancer.

Nanomedicine: Photo-activated nanostructured titanium dioxide, as a promising anticancer agent

The multivariate condition of cancer disease has been approached in various ways, by the scientific community. Recent studies focus on individualized treatments, minimizing the undesirable consequences of the conventional methods, but the development of an alternative effective therapeutic scheme remains to be held. Nanomedicine could provide a solution, filling this gap, exploiting the unique properties of innovative nanostructured materials. Nanostructured titanium dioxide (TiO₂) has a variety of applications of daily routine and of advanced technology. Due to its biocompatibility, it has also a great number of biomedical applications. It is now clear that photo-excited TiO₂ nanoparticles, induce generation of pairs of electrons and holes which react with water and oxygen to yield reactive oxygen species (ROS) that have been proven to damage cancer cells, triggering controlled cellular processes. The aim of this review is to provide insights into the field of nanomedicine and particularly into the wide context of TiO₂-NP-mediated anticancer effect, shedding light on the achievements of nanotechnology and proposing this nanostructured material as a promising anticancer photosensitizer.

Nanoapproaches to Modifying Epigenetics of Epithelial Mesenchymal Transition for Treatment of Pulmonary Fibrosis

Idiopathic Pulmonary Fibrosis (IPF) is a chronically progressive interstitial lung that affects over 3 M people worldwide and rising in incidence. With a median survival of 2-3 years, IPF is consequently associated with high morbidity, mortality, and healthcare burden. Although two antifibrotic therapies, pirfenidone and nintedanib, are approved for human use, these agents reduce the rate of decline of pulmonary function but are not curative and do not reverse established fibrosis. In this review, we discuss the prevailing epithelial injury hypothesis, wherein pathogenic airway epithelial cell-state changes known as Epithelial Mesenchymal Transition (EMT) promotes the expansion of myofibroblast populations. Myofibroblasts are principal components of extracellular matrix production that result in airspace loss and mortality. We review the epigenetic transition driving EMT, a process produced by changes in histone acetylation regulating mesenchymal gene expression programs. This mechanistic work has focused on the central role of bromodomain-containing protein 4 in mediating EMT and myofibroblast transition and initial preclinical work has provided evidence of efficacy. As nanomedicine presents a promising approach to enhancing the efficacy of such anti-IPF agents, we then focus on the state of nanomedicine formulations for inhalable delivery in the treatment of pulmonary diseases, including liposomes, polymeric nanoparticles (NPs), inorganic NPs, and exosomes. These nanoscale agents potentially provide unique properties to existing pulmonary therapeutics, including controlled release, reduced systemic toxicity, and combination delivery. NP-based approaches for pulmonary delivery thus offer substantial promise to modify epigenetic regulators of EMT and advance treatments for IPF.

Creating Structured Hydrogel Microenvironments for Regulating Stem Cell Differentiation

The development of distinct biomimetic microenvironments for regulating stem cell behavior and bioengineering human tissues and disease models requires a solid understanding of cell-substrate interactions, adhesion, and its role in directing cell behavior, and other physico-chemical cues that drive cell behavior. In the past decade, innovative developments in chemistry, materials science, microfabrication, and associated technologies have given us the ability to manipulate the stem cell microenvironment with greater precision and, further, to monitor effector impacts on stem cells, both spatially and temporally. The influence of biomaterials and the 3D microenvironment's physical and biochemical properties on mesenchymal stem cell proliferation, differentiation, and matrix production are the focus of this review chapter. Mechanisms and materials, principally hydrogel and hydrogel composites for bone and cartilage repair that create "cell-supportive" and "instructive" biomaterials, are emphasized. We begin by providing an overview of stem cells, their unique properties, and their challenges in regenerative medicine. An overview of current fabrication strategies for creating instructive substrates is then reviewed with a focused discussion of selected fabrication methods with an emphasis on bioprinting as a critical tool in creating novel stem cell-based biomaterials. We conclude with a critical assessment of the current state of the field and offer our view on the promises and potential pitfalls of the approaches discussed.

Recent advances in understanding oligonucleotide aptamers and their applications as therapeutic agents

The innovative discovery of aptamers was based on target-specific treatment in clinical diagnostics and therapeutics. Aptamers are synthetic, single-stranded oligonucleotides, simply described as chemical antibodies, which can bind to diverse targets with high specificity and affinity. Aptamers are synthesized by the SELEX technique, and possess distinctive properties as small size (10-50 kDa), higher stability, easy manufacture and less immunogenicity. These oligonucleotides are easily degraded by nucleases, so require some important modifications like capping and incorporation of modified nucleotides. RNA aptamers can be modified chemically on 2' positions using -NH3, -F, -deoxy, or -OMe groups to enhance their nuclease resistance. Aptamers have been employed for multiple purposes, as direct drugs or aptamer-drug conjugates targeted against different diseased cells. Different aptamer-conjugated nanovehicles (e.g., micelles, liposomes, silica nano-shells) have been designed to transport diverse anticancer-drugs like doxorubicin and cisplatin in bulk to minimize systemic cytotoxicity. Some drug-loaded nanovehicles (up to 97% loading capacity) and conjugated with specific aptamer resulted in more than 60% tumor inhibition as compared to unconjugated drug-loaded nanovehicles which showed only 31% cancer inhibition. In addition, aptamers have been widely used in basic research, food safety, environmental monitoring, clinical diagnostics and therapeutics. Different FDA-approved RNA and DNA aptamers are now available in the market, used for the treatment of diverse diseases, especially cancer. These aptamers include Macugen, Pegaptanib, etc. Despite a good progress in aptamer use, the present-day chemotherapeutics and drug targeting systems still face great challenges. Here in this review article, we are discussing nucleic acid aptamers, preparation, role in the transportation of different nanoparticle vehicles and their applications as therapeutic agents.

Synthesis, characterization and biocompatibility studies of carbon quantum dots from Phoenix dactylifera

In the present study, Carbon Quantum Dots (CQDs) were synthesized from Phoenix dactylifera (Date palm fruit) using microwave-assisted pyrolysis and were characterized for its various properties. The synthesized CQD sample exhibited a narrow absorbance peak at 270 nm in UV-Vis spectrum that indicated generation of narrow sized particles. The FTIR analysis of the crude CQDs and dialysed sample revealed the various functional groups involved in the formation of CQDs. TEM data revealed the nature of CQDs to be quasi-spherical and spatially distributed. Biocompatibility of the CQDs was studied using various model systems. CQDs displayed no cytotoxic and anti-clonogenic property when exposed to WRL-68 cell line whereas a slight toxicity was evident in HT1080 post 24 h of incubation suggesting the tremendous potential of the CQDs in the synergistic killing of cancer cells. Phytotoxicity assessment in four different seedlings revealed the non-toxic nature of CQDs. Further these CQDs were found to possess high biocompatibility imposing no inhibition in microbial growth and zilch effect on the development of zebrafish embryos. Thus these CQDs can find immense potential applications in fields of biomedicine as biomolecule detection, drug carriers, fluorescent tracers and in controlling the drug release.

Synthesis of Metal Nanostructures Using Supercritical Carbon Dioxide: A Green and Upscalable Process

Metallic nanostructures have numerous applications as industrial catalysts and sensing platforms. Supercritical carbon dioxide (scCO₂ ) is a green medium for the scalable preparation of nanomaterials. Supercritical fluid reactive deposition (SFRD) and other allied techniques can be employed for the mass production of metal nanostructures for various applications. The present article reviews the recent reports on the scCO₂ -assisted preparation of zero-valent metal nanomaterials and their applications. A brief description of the science of pure supercritical fluids, especially CO₂ , and the basics of binary mixtures composed of scCO₂ and a low volatile substance, e.g., an organometallic precursor are presented. The benefits of using scCO₂ for preparing metal nanomaterials, especially as a green solvent, are also being highlighted. The experimental conditions that are useful for the tuning of particle properties are reviewed thoroughly. The range of modifications to the classical SFRD methods and the variety of metallic nanomaterials that can be synthesized are reviewed and presented. Finally, the broad ranges of applications that are reported for the metallic nanomaterials that are synthesized using scCO₂ are reviewed. A brief summary along with perspectives about future research directions is also presented.

Green Synthesis of Silver Nanoparticles Using Astragalus tribuloides Delile. Root Extract: Characterization, Antioxidant, Antibacterial, and Anti-Inflammatory Activities

Today, the green synthesis of metal nanoparticles is a promising strategy in material science and nanotechnology. In this research, silver nanoparticles (AgNPs) were synthesized through the high-efficient, cost-effective green and facile process, using the Astragalus tribuloides Delile. root extract as a bioreduction and capping agent at room temperature. UV-Vis spectroscopy was applied for the investigation of the reaction proceedings. To characterize the greenly synthesized AgNPs, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction spectroscopy (XRD), and transmission electron microscopy (TEM) analyses were utilized. In addition, the total phenolics and flavonoids contents, antioxidant, antibacterial, and anti-inflammatory activities of the greenly synthesized AgNPs and the A. tribuloides root extract were evaluated. The results indicated that the AgNPs had spherical morphology and crystalline structure with the average size of 34.2 ± 8.0 nm. The total phenolics and flavonoids contents of the greenly synthesized AgNPs were lower than those for the A. tribuloides root extract. The resultant AgNPs exhibited the appropriate antioxidant activity (64%) as compared to that for the A. tribuloides root extract (47%). The antibacterial test approved the higher bactericidal activity of the resulting AgNPs on the Gram-positive and Gram-negative bacteria in comparison to the A. tribuloides root extract. Considering the anti-inflammatory activity, the greenly synthesized AgNPs showed a stranger effect than the A. tribuloides root extract (82% versus 69% at 500 μg/mL). Generally, the AgNPs that were fabricated by using the A. tribuloides root extract had appropriate antioxidant, antibacterial, and anti-inflammatory activities and, therefore, can be considered as a promising candidate for various biomedical applications.

Water safety screening via multiplex LAMP-Au-nanoprobe integrated approach

Contaminated water resources remain a major global concern regarding public health. The majority of water safety protocols include indicators of microbial contamination to evaluate the potential risk to public health and are key elements of quality guidelines. Among these, markers for total coliforms and fecal coliforms are strong indicators of co-contamination with other pathogens. Traditional methods, recurring to slow and cumbersome culture-based approaches, have been gradually replaced by molecular methods, capable of faster and more specific screening. These are usually PCR-based methods that may allow for multiple pathogen detection but require dedicated laboratory equipment, hindering the rapid on-site assessment. Here, we used a multiplex Loop-Mediated Isothermal Amplification (mLAMP) strategy for the amplification of two markers associated with the contamination by total and fecal coliforms (e.g. Escherichia coli) - lacZ and uidA genes, respectively - thus allowing for single tube multiplex detection. The mLAMP products were then subject to an Au-nanoprobe colorimetric detection assay for precise discrimination of targets. This approach was validated in 22 water samples that were also screened for the presence of lacZ and uidA using standard and quantitative PCR, with the capability for discriminating the contamination level, e.g. a semi-quantitative evaluation of water quality.

Characterization and antibacterial of Gold Nanoparticles Prepared by Electrolysis method

In this study gold nanoparticles (AuNPs) was prepared by electrolysis method Au thin film which was deposited on a glass substrate by drop-casting technique structural, optical and topographic characteristic of prepared nanoparticles were examined by UV-VIS absorption, TEM electron microscopy, AFM atomic microscopy, and XRD diffraction. Antibacterial activity of nanoparticles has been investigated against many pathogenic bacteria, including Escherichia coli, Staphylococcus aureus, bacillus and Pseudomonas aeruginosa using a well-spread method, and the results showed that nanoparticles have an inhibitory effect against all types of pathogenic bacteria For diseases. And 30 and 25 mm) for aerosols, E. coli, Bacillus subtilis, Staphylococcus aureus and Staphylococcus aureus, respectively.

Current Research of Graphene-Based Nanocomposites and Their Application for Supercapacitors

This review acmes the latest developments of composites of metal oxides/sulfide comprising of graphene and its analogues as electrode materials in the construction of the next generation of supercapacitors (SCs). SCs have become an indispensable device of energy-storage modes. A prompt increase in the number of scientific accomplishments in this field, including publications, patents, and device fabrication, has evidenced the immense attention they have attracted from scientific communities. These efforts have resulted in rapid advancements in the field of SCs, focusing on the development of electrode materials with features of high performance, economic viability, and robustness. It has been demonstrated that carbon-based electrode materials mixed with metal oxides and sulfoxides can perform extremely well in terms of energy density, durability, and exceptional cyclic stability. Herein, the state-of-the-art technologies relevant to the fabrication, characterization, and property assessment of graphene-based SCs are discussed in detail, especially for the composite forms when mixing with metal sulfide, metal oxides, metal foams, and nanohybrids. Effective synthetic methodologies for the nanocomposite fabrications via intercalation, coating, wrapping, and covalent interactions will be reviewed. We will first introduce some fundamental aspects of SCs, and briefly highlight the impact of graphene-based nanostructures on the basic principle of SCs, and then the recent progress in graphene-based electrodes, electrolytes, and all-solid-state SCs will be covered. The important surface properties of the metal oxides/sulfides electrode materials (nickel oxide, nickel sulfide, molybdenum oxide, ruthenium oxides, stannous oxide, nickel-cobalt sulfide manganese oxides, multiferroic materials like BaMnF, core-shell materials, etc.) will be described in each section as per requirement. Finally, we will show that composites of graphene-based electrodes are promising for the construction of the next generation of high performance, robust SCs that hold the prospects for practical applications.

Nanotechnology-based drug delivery systems for enhanced diagnosis and therapy of oral cancer

Oral cancer is a common malignant life-threatening tumor. Despite some advances in traditional therapy, mortality and mobidity rates are high due to delayed diagnosis and ineffective treatment. Additionally, some patients inevitably suffer from various fatal adverse effects during the course of therapy. Therefore, it is imperative to develop novel methods to eradicate oral cancer cells with minimal adverse effects on normal cells. Nanotechnology is a promising and novel vehicle for the diagnosis and treatment of oral cancer with encouraging recent achievements. In this review, we present state-of-the-art nanotechnology-based drug delivery systems employed in the domain of oral cancer, especially for its enhanced diagnosis and therapy. We describe in detail the types of nanotechnology used in the management of oral cancer and summarize administration routes of nanodrugs. Finally, the potential and prospects of nanotechnology-based drug delivery systems as promising modalities of diagnosis and therapy of oral cancer are highlighted.

The challenge of using nanotherapy during pregnancy: Technological aspects and biomedical implications

During the period of pregnancy, several processes and physiological adaptations occur in the body and metabolism of pregnant woman. These physiological adaptations in pregnant woman end up leading to a suppression in immune system favoring obstetric complications to the mother, fetus and placental tissue. An effective pharmacological therapy for these complications is still a challenge, since some drugs during pregnancy can have deleterious and teratogenic effects. An emerging alternative to pharmacological therapy during pregnancy is drugs encapsulated in nanoparticles (NP), recent area called nano-obstetrics. NP have the advantage of drug targeting and reduction of side effects. Then, maternal, placental or fetal uptake can be expected, depending on the characteristics of NP. Inorganic NP, crossing placental barrier effectively, but have several nanotoxicological effects. While organic NP appear to have a better targeting capacity and have few toxicological effects, but the studies are still scarce. Thus, in this review, were examined questions related to use and impact of physicochemical aspects of inorganic and organic NP during pregnancy.

Highly stable AgNPs prepared via a novel green approach for catalytic and photocatalytic removal of biological and non-biological pollutants

Increases in biological and non-biological pollutants pose a significant threat to environmental systems. In an effort to develop an effective means to treat such pollutants, the use of Phaseolus vulgaris (kidney beans) as reducing and capping agents is proposed for the green synthesis of highly stable silver nanoparticles (AgNPs) with a face-centered cubic (fcc) crystalline structure (size range: 10-20 nm). The potent role of the resulting AgNPs was found as triple platforms (photocatalyst, catalyst, and antimicrobial disinfectant). AgNPs were able to photocatalytically degrade approximately 97% of reactive red-141 (RR-141) dye within 150 min of exposure (quantum efficiency of 3.68 × 10^-6 molecule.photon^-1 and a removal reaction kinetic rate of 1.13 × 10^-2 mmol g^-1 h^-1). The role of specific reactive oxygen species (ROS) in the photocatalytic process and complete mineralization of dye was also explored through scavenger and chemical oxygen demand (COD) experiments, respectively. As an catalyst, AgNPs were also capable of reducing 4-nitrophenol to 4-aminophenol within 15 min. Overall, AgNPs showed excellent stability as catalyst and photocatalyst even after five test cycles. As an antimicrobial agent, the AgNPs are effective against both gram-positive (Bacillus subtilis) and -negative bacteria (Escherichia coli), with the zones of clearance as 15 and 18 mm, respectively. Thus, the results of this study validate the triple role of AgNPs derived via green synthesis as a photocatalyst, catalyst, and antimicrobial agent for effective environmental remediation.

Nanocarriers for effective nutraceutical delivery to the brain

Neurodegenerative disorders are common among aging populations around the globe. Most are characterized by loss of neurons, protein aggregates, oxidative stress, mitochondrial damage, neuroinflammation among others. Although symptomatic treatment using conventional pharmacotherapy has been widely employed, their therapeutic success is limited due to varied reasons. In the need to identify an alternative approach, researchers successfully demonstrated the therapeutic utility of plant-derived nutraceuticals in cell and animal models of neurodegenerative conditions. However, most nutraceuticals failed during clinical trials in humans owing to their poor bioavailability in vivo and limited permeability across the blood brain barrier (BBB). The current emphasis is therefore on the improved delivery of nutraceuticals to the brain. In this regard, development of nanoparticle conjugated nutraceuticals to enhance bioavailability and therapeutic efficacy in the brain has gained attention. Here, we review the research advances in nanoparticles conjugated nutraceuticals applied in neurodegenerative disorders and discuss their advantages and limitations, clinical trials and toxicity concerns.

Citrate-silver nanoparticles and their impact on some environmental beneficial fungi

Colloidal suspensions of silver nanoparticles (AgNPs) with surface modified by capping with citrate ions were synthesized by chemical reduction method. Transmission and Scanning Electron Microscopy as well as darkfield Optical Microscopy provided information on the nanoparticle morphology, with fine symmetrical grains and log-normal fitted size distribution. Small Angle X-ray Scattering method allowed theoretical confirmation of colloidal silver nanoparticle fine granularity, based on measurements in the native fluid sample. UV–Vis spectrophotometry allowed studying the Localized Surface Plasmon Resonance band versus the stability of the citrate-AgNP sample after storage and after UV-C exposure. The colloidal AgNP impact on Phanerochaete chrysosporium environmental microorganisms was studied by specific biochemical investigations. Silver released from the colloidal suspension of AgNPs was supposed to induce changes in some antioxidant enzymes and in some enzymes of Krebs’ cycle. Catalase activity was moderately changed (an increase with over 50%) as well as superoxide dismutase activity, while the diminution of the activities of four dehydrogenases synthesized in the fungus mycelium was emphasized also: a decrease with about 60% for malate dehydrogenase, with over 50% for isocitrate dehydrogenase and succinate dehydrogenase and with about 40% for alpha-ketoglutarate dehydrogenase. These findings suggested the nano-toxicological issues of citrate-AgNPs impact on the environmental beneficial microorganisms.

Nanotechnology and Animal Health

Nanotechnology has been a rapidly expanding area of research with huge potential in many sectors, including animal healthcare. It promises to revolutionize drug and vaccine delivery, diagnostics, and theranostics, which has become an important tool in personalized medicine by integrating therapeutics and diagnostics. Nanotechnology has also been used successfully in animal nutrition. In this review, the application of nanotechnology in animal health will be reviewed with its pros and cons.

Trends in Nanomedicines for Cancer Treatment

Background:

Cancer is characterized by abnormal cell growth and considered one of the leading causes of death around the world. Pharmaceutical Nanotechnology has been extensively studied for the optimization of cancer treatment.

Objective:

Comprehend the panorama of Pharmaceutical Nanotechnology in cancer treatment, through a survey about nanomedicines applied in clinical studies, approved for use and patented.

Methods:

Acknowledged products under clinical study and nanomedicines commercialized found in scientific articles through research on the following databases: Pubmed, Science Direct, Scielo and Lilacs. Derwent tool was used for patent research.

Results:

Nanomedicines based on nanoparticles, polymer micelles, liposomes, dendrimers and nanoemulsions were studied, along with cancer therapies such as Photodynamic Therapy, Infrared Phototherapy Hyperthermia, Magnetic Hyperthermia, Radiotherapy, Gene Therapy and Nanoimmunotherapy. Great advancement has been observed over nanotechnology applied to cancer treatment, mainly for nanoparticles and liposomes.

Conclusion:

The combination of drugs in nanosystems helps to increase efficacy and decrease toxicity. Based on the results encountered, nanoparticles and liposomes were the most commonly used nanocarriers for drug encapsulation. In addition, although few nanomedicines are commercially available, this specific research field is continuously growing.

The uses of resveratrol for neurological diseases treatment and insights for nanotechnology based-drug delivery systems

Neurological disorders have been growing in recent years and are highly prevalent globally. Resveratrol (RES) is a natural product from plant sources such as grape skins. This compound has shown biological activity in many diseases, in particular, those that act on the central nervous system. The mechanism of action and the key points in neurological disorders were described and show the targeted mechanism of action. Due to the insolubility of this compound; the use of nanotechnology-based systems has been proposed for the incorporation of RES and RES-loaded nanocarriers have been designed for intranasal administration, oral or parenteral routes to deliver it to the brain. In general, these nanosystems have shown to be effective in many studies, pharmacological and pharmacokinetic assays, as well as some cell studies. The outcomes show that RES has been reported in human clinical trials for some neurological diseases, although no studies were performed in humans using nanocarriers, animal and/or cellular models have been reported to show good results regarding therapeutics on neurological diseases. Thus, the use of this nutraceutical has shown true for neurological diseases and its loading into nanocarriers displaying good results on the stability, delivery and targeting to the brain.