Multifunctional Gold Nanoparticles: A Novel Nanomaterial for Various Medical Applications and Biological Activities

Actively targeted photodynamic therapy in multicellular colorectal cancer spheroids via functionalised gold nanoparticles

Photodynamic therapy (PDT) holds great potential to overcome limitations associated with common colorectal cancer (CRC) treatment approaches. Targeted photosensitiser (PS) delivery systems using nanoparticles (NPs) with targeting moieties are continually being designed, which are aimed at enhancing PS efficacy in CRC PDT. However, the optimisation of targeted PS delivery systems in most, in vitro PDT studies has been conducted on two dimensional (2D) monolayers cell cultures. In our present study, we developed a nano PS delivery system for in vitro cultured human colorectal three-dimensional multicellular spheroids (3D MCTS). PEGylated gold nanoparticles (PEG-AuNPs) were prepared and attached to ZnPcS4PS and further functionalised with specific CRC targeting anti-Guanylate Cyclase monoclonal antibodies(mAb). The ZnPcS4-AuNP-Anti-GCC Ab (BNC) nanoconjugates were successfully synthesised and their photodynamic effect investigated following exposure to laser irradiation and demonstrated enhanced anticancer effects in Caco-2 cells cultivated as 3D MCTS spheroids. Our findings suggest that targeted BNC nanoconjugates can improve the efficacy of PDT and highlight the potential of 3D MCTS tumour model for evaluating of targeted PDT.

Identifying factors controlling cellular uptake of gold nanoparticles by machine learning

There is strong interest to improve the therapeutic potential of gold nanoparticles (GNPs) while ensuring their safe development. The utility of GNPs in medicine requires a molecular-level understanding of how GNPs interact with biological systems. Despite considerable research efforts devoted to monitoring the internalisation of GNPs, there is still insufficient understanding of the factors responsible for the variability in GNP uptake in different cell types. Data-driven models are useful for identifying the sources of this variability. Here, we trained multiple machine learning models on 2077 data points for 193 individual nanoparticles from 59 independent studies to predict cellular uptake level of GNPs and compared different algorithms for their efficacies of prediction. The five ensemble learners (Xgboost, random forest, bootstrap aggregation, gradient boosting, light gradient boosting machine) made the best predictions of GNP uptake, accounting for 80-90% of the variance in the test data. The models identified particle size, zeta potential, GNP concentration and exposure duration as the most important drivers of cellular uptake. We expect this proof-of-concept study will foster the more effective use of accumulated cellular uptake data for GNPs and minimise any methodological bias in individual studies that may lead to under- or over-estimation of cellular internalisation rates.

Nanomaterials-assisted gene editing and synthetic biology for optimizing the treatment of pulmonary diseases

The use of nanomaterials in gene editing and synthetic biology has emerged as a pivotal strategy in the pursuit of refined treatment methodologies for pulmonary disorders. This review discusses the utilization of nanomaterial-assisted gene editing tools and synthetic biology techniques to promote the development of more precise and efficient treatments for pulmonary diseases. First, we briefly outline the characterization of the respiratory system and succinctly describe the principal applications of diverse nanomaterials in lung ailment treatment. Second, we elaborate on gene-editing tools, their configurations, and assorted delivery methods, while delving into the present state of nanomaterial-facilitated gene-editing interventions for a spectrum of pulmonary diseases. Subsequently, we briefly expound on synthetic biology and its deployment in biomedicine, focusing on research advances in the diagnosis and treatment of pulmonary conditions against the backdrop of the coronavirus disease 2019 pandemic. Finally, we summarize the extant lacunae in current research and delineate prospects for advancement in this domain. This holistic approach augments the development of pioneering solutions in lung disease treatment, thereby endowing patients with more efficacious and personalized therapeutic alternatives.

The phototoxic effect of a gold-antibody-based nanocarrier of phthalocyanine on melanoma monolayers and tumour spheroids

In recent years, photodynamic therapy (PDT) has garnered significant attention in cancer treatment due to its increased potency and non-invasiveness compared to conventional therapies. Active-targeted delivery of photosensitizers (PSs) is a mainstay strategy to significantly reduce its off-target toxicity and enhance its phototoxic efficacy. The anti-melanoma inhibitory activity (MIA) antibody is a targeting biomolecule that can be integrated into a nanocarrier system to actively target melanoma cells due to its specific binding to MIA antigens that are highly expressed on the surface of melanoma cells. Gold nanoparticles (AuNPs) are excellent nanocarriers due to their ability to encapsulate a variety of therapeutics, such as PSs, and their ability to bind with targeting moieties for improved bioavailability in cancer cells. Hence, we designed a nanobioconjugate (NBC) composed of zinc phthalocyanine tetrasulfonic acid (ZnPcS4), AuNPs and anti-MIA Ab to improve ZnPcS4 bioavailability and phototoxicity in two and three-dimensional tumour models. In summary, we demonstrated that this nanobioconjugate showed significant inhibitory effects on both melanoma models due to increased ROS yields and bioavailability of the melanoma cells compared to free ZnPcS4.

Optical Tweezing Terahertz Probing for a Single Metal Nanoparticle

Recently, extensive research has been reported on the detection of metal nanoparticles using terahertz waves, due to their potential for efficient and nondestructive detection of chemical and biological samples without labeling. Resonant terahertz nanoantennas can be used to detect a small amount of molecules whose vibrational modes are in the terahertz frequency range with high sensitivity. However, the positioning of target molecules is critical to obtaining a reasonable signal because the field distribution is inhomogeneous over the antenna structure. Here, we combine an optical tweezing technique and terahertz spectroscopy based on nanoplasmonics, resulting in extensive controllable tweezing and sensitive detection at the same time. We observed optical tweezing of a gold nanoparticle and detected it with terahertz waves by using a single bowtie nanoantenna. Furthermore, the calculations confirm that molecular fingerprinting is possible by using our technique. This study will be a prestep of biomolecular detection using gold nanoparticles in terahertz spectroscopy.

Single-Domain Antibody-Gold Nanoparticle Bioconjugates as Immunosensors for the Detection of Hantaviruses

INTRODUCTION

Hantavirus, a zoonotic pathogen, causes severe syndromes like hemorrhagic fever with renal syndrome (HFRS), sometimes fatal in humans. Considering the importance of detecting the hantavirus antigen, the construction of an immunosensor is essential. The structural and functional characteristics of camelid nanobodies (VHHs) encourage their application in the areas of nanobiotechnology, therapeutics, diagnostics, and basic research. Therefore, this study aimed to standardize stable bioconjugates using gold nanoparticles (AuNPs) and VHHs, in order to develop immunobiosensors for the diagnosis of hantavirus infection.

METHODS

Immobilized metal affinity chromatography (IMAC) was performed to obtain purified recombinant anti-hantavirus nucleocapsid nanobodies (anti-prNΔ85 VHH), while AuNPs were synthesized for bioconjugation. UV-visible spectrophotometry and transmission electron microscopy (TEM) analysis were employed to characterize AuNPs.

RESULTS

The bioconjugation stability parameters (VHH-AuNPs), analyzed by spectrophotometry, showed that the ideal pH value and VHH concentration were obtained at 7.4 and 50 μg/mL, respectively, after addition of 1 M NaCl, which induces AuNP aggregation. TEM performed before and after bioconjugation showed uniform, homogeneous, well-dispersed, and spherical AuNPs with an average diameter of ~ 14 ± 0.57 nm. Furthermore, high-resolution images revealed a thin white halo on the surface of the AuNPs, indicating the coating of the AuNPs with protein. A biosensor simulation test (dot blot-like [DB-like]) was performed in stationary phase to verify the binding and detection limits of the recombinant nucleocapsid protein from the Araucária hantavirus strain (prN∆85).

DISCUSSION

Using AuNPs/VHH bioconjugates, a specific interaction was detected between 5 and 10 min of reaction in a dose-dependent manner. It was observed that this test was sensitive enough to detect prNΔ85 at concentrations up to 25 ng/μL. Considering that nanostructured biological systems such as antibodies conjugated with AuNPs are useful tools for the development of chemical and biological sensors, the stability of the bioconjugate indicates proficiency in detecting antigens. The experimental results obtained will be used in a future immunospot assay or lateral flow immunochromatography analysis for hantavirus detection.

The Optimization of the One-Pot Synthesis of Au@SiO2Core-Shell Nanostructures: Modification with Dansyl Group and Their Fluorescent Properties

This work describes the optimization of the one-pot synthesis of fine core-shell nanostructures based on nanogold (Au NPs) and silica (SiO2). The obtained core-shell nanomaterials were characterized by Transmission Electron Microscopy (TEM and by the method of spectroscopes such as UV-Vis Spectroscopy and Fourier Transform Infrared Spectroscopy (FT-IR). In addition, the measurement of the zeta potential and size of the obtained particles helped present a full characterization of Au@SiO2 nanostructures. The results show that the influence of reagents acting as reducers, stabilizers, or precursors of the silica shell affects the morphology of the obtained material. By controlling the effect of the added silica precursor, the thickness of the shell can be manipulated, the reducer has an effect on the shape and variety, and then the stabilizer affects their agglomeration. This work provides also a new approach for Au@SiO2core-shell nanostructure preparation by further modification with dansyl chloride (DNS-Cl). The results show that, by tuning the silica shell thickness, the intensity of the fluorescence spectrum of Au@SiO2-(CH2)3-NH-DNS nanocomposite is about 12 times higher than that of DNS-Cl.

Long-Term Accumulation, Biological Effects and Toxicity of BSA-Coated Gold Nanoparticles in the Mouse Liver, Spleen, and Kidneys

Introduction

Gold nanoparticles are promising candidates as vehicles for drug delivery systems and could be developed into effective anticancer treatments. However, concerns about their safety need to be identified, addressed, and satisfactorily answered. Although gold nanoparticles are considered biocompatible and nontoxic, most of the toxicology evidence originates from in vitro studies, which may not reflect the responses in complex living organisms.

Methods

We used an animal model to study the long-term effects of 20 nm spherical AuNPs coated with bovine serum albumin. Mice received a 1 mg/kg single intravenous dose of nanoparticles, and the biodistribution and accumulation, as well as the organ changes caused by the nanoparticles, were characterized in the liver, spleen, and kidneys during 120 days.

Results

The amount of nanoparticles in the organs remained high at 120 days compared with day 1, showing a 39% reduction in the liver, a 53% increase in the spleen, and a 150% increase in the kidneys. The biological effects of chronic nanoparticle exposure were associated with early inflammatory and fibrotic responses in the organs and were more pronounced in the kidneys, despite a negligible amount of nanoparticles found in renal tissues.

Conclusion

Our data suggest, that although AuNPs belong to the safest nanomaterial platforms nowadays, due to their slow tissue elimination leading to long-term accumulation in the biological systems, they may induce toxic responses in the vital organs, and so understanding of their long-term biological impact is important to consider their potential therapeutic applications.

Metallic nanoparticles and photosynthesis organisms: Comprehensive review from the ecological perspective

This review presents a comprehensive analysis of the ecological implications of metallic nanoparticles (MNPs) on photosynthetic organisms, particularly plants and algae. We delve into the toxicological impacts of various MNPs, including gold, silver, copper-based, zinc oxide, and titanium dioxide nanoparticles, elucidating their effects on the growth and health of these organisms. The article also summarizes the toxicity mechanisms of these nanoparticles in plants and algae from previous research, providing insight into the cellular and molecular interactions that underpin these effects. Furthermore, it discusses the reciprocal interactions between different types of MNPs, their combined effects with other metal contaminants, and compares the toxicity between MNPs with their counterpart. This review highlights the urgent need for a deeper understanding of the environmental impact, considering their escalating use and the potential risks they pose to ecological systems, especially in the context of photosynthetic organisms that are vital to ecosystem health and stability.

211At on gold nanoparticles for targeted radionuclide therapy application

Targeted alpha therapy (TAT) is a methodology that is being developed as a promising cancer treatment using the α-particle decay of radionuclides. This technique involves the use of heavy radioactive elements being placed near the cancer target area to cause maximum damage to the cancer cells while minimizing the damage to healthy cells. Using gold nanoparticles (AuNPs) as carriers, a more effective therapy methodology may be realized. AuNPs can be good candidates for transporting these radionuclides to the vicinity of the cancer cells since they can be labeled not just with the radionuclides, but also a host of other proteins and ligands to target these cells and serve as additional treatment options. Research has shown that astatine and iodine are capable of adsorbing onto the surface of gold, creating a covalent bond that is quite stable for use in experiments. However, there are still many challenges that lie ahead in this area, whether they be theoretical, experimental, and even in real-life applications. This review will cover some of the major developments, as well as the current state of technology, and the problems that need to be tackled as this research topic moves along to maturity. The hope is that with more workers joining the field, we can make a positive impact on society, in addition to bringing improvement and more knowledge to science.

A comprehensive review on the biomedical frontiers of nanowire applications

This comprehensive review examines the immense capacity of nanowires, nanostructures characterized by unbounded dimensions, to profoundly transform the field of biomedicine. Nanowires, which are created by combining several materials using techniques such as electrospinning and vapor deposition, possess distinct mechanical, optical, and electrical properties. As a result, they are well-suited for use in nanoscale electronic devices, drug delivery systems, chemical sensors, and other applications. The utilization of techniques such as the vapor-liquid-solid (VLS) approach and template-assisted approaches enables the achievement of precision in synthesis. This precision allows for the customization of characteristics, which in turn enables the capability of intracellular sensing and accurate drug administration. Nanowires exhibit potential in biomedical imaging, neural interfacing, and tissue engineering, despite obstacles related to biocompatibility and scalable manufacturing. They possess multifunctional capabilities that have the potential to greatly influence the intersection of nanotechnology and healthcare. Surmounting present obstacles has the potential to unleash the complete capabilities of nanowires, leading to significant improvements in diagnostics, biosensing, regenerative medicine, and next-generation point-of-care medicines.

Biosynthesized metallic nanoparticles: A new era in cancer therapy

Cancer remains a global health crisis, claiming countless lives throughout the years. Traditional cancer treatments like chemotherapy and radiation often bring about severe side effects, underscoring the pressing need for innovative, more efficient, and less toxic therapies. Nanotechnology has emerged as a promising technology capable of producing environmentally friendly anticancer nanoparticles. Among various nanoparticle types, metal-based nanoparticles stand out due to their exceptional performance and ease of use in methods of imaging. The widespread accessibility of biological precursors for synthesis based on plants of metal nanoparticles has made large-scale, eco-friendly production feasible. This evaluation provides a summary of the green strategy for synthesizing metal-based nanoparticles and explores their applications. Moreover, this review delves into the potential of phyto-based metal nanoparticles in combating cancer, shedding light on their probable mechanisms of action. These insights are invaluable for enhancing both biomedical and environmental applications. The study also touches on the numerous potential applications of nanotechnology in the field of medicine. Consequently, this research offers a concise and well-structured summary of nanotechnology, which should prove beneficial to researchers, engineers, and scientists embarking on future research endeavors.

Antibacterial Properties of an Experimental Dental Resin Loaded with Gold Nanoshells for Photothermal Therapy Applications

This study explored the chemical and antibacterial properties of a dental resin loaded with gold nanoshells (AuNPs) in conjunction with photothermal therapy (PTT) as a novel method against Streptococcus mutans (S. mutans) to prevent secondary caries. First, a 20-h minimum inhibitory concentration (MIC) assay was performed on solutions of AuNPs with planktonic S. mutans under an LED device and laser at 660 nm. Next, resin blends containing 0, 1 × 1010, or 2 × 1010 AuNPs/mL were fabricated, and the degree of conversion (DC) was measured using an FTIR spectroscopy. Lastly, a colony forming unit (CFU) count was performed following 24 h growth of S. mutans on 6 mm diameter resin disks with different light treatments of an LED device and a laser at 660 nm. The MIC results only showed a reduction in S. mutans at AuNP concentrations less than 3.12 µg/mL under a laser illumination level of 95.5 J/cm2 compared to the dark treatment (p < 0.010 for each). CFU and DC results showed no significant dependence on any light treatment studied. The AuNPs expressed antibacterial effects following PPT against planktonic S. mutans but not in a polymerized dental adhesive resin. Future studies should focus on different shapes, structure, and concentrations of AuNPs loaded in a resin blend.

Biomolecular Corona of Gold Nanoparticles: The Urgent Need for Strong Roots to Grow Strong Branches

Gold nanoparticles (GNPs) are largely employed in diagnostics/biosensors and are among the most investigated nanomaterials in biology/medicine. However, few GNP-based nanoformulations have received FDA approval to date, and promising in vitro studies have failed to translate to in vivo efficacy. One key factor is that biological fluids contain high concentrations of proteins, lipids, sugars, and metabolites, which can adsorb/interact with the GNP's surface, forming a layer called biomolecular corona (BMC). The BMC can mask prepared functionalities and target moieties, creating new surface chemistry and determining GNPs' biological fate. Here, the current knowledge is summarized on GNP-BMCs, analyzing the factors driving these interactions and the biological consequences. A partial fingerprint of GNP-BMC analyzing common patterns of composition in the literature is extrapolated. However, a red flag is also risen concerning the current lack of data availability and regulated form of knowledge on BMC. Nanomedicine is still in its infancy, and relying on recently developed analytical and informatic tools offers an unprecedented opportunity to make a leap forward. However, a restart through robust shared protocols and data sharing is necessary to obtain "stronger roots". This will create a path to exploiting BMC for human benefit, promoting the clinical translation of biomedical nanotools.

The Biofilm Inhibition Properties of Glucosamine Gold Nanoparticles in Combination with Meropenem against Pseudomonas aeruginosa on the Endotracheal Tube: A Model of Biofilm-Related Ventilator-Associated Pneumonia

Biofilm-related infections play a significant role in the development and persistence of ventilator-associated pneumonia. Pseudomonas aeruginosa (P. aeruginosa) frequently causes biofilm-related infections associated with ventilator tubing. Glucosamine gold nanoparticles (AuNPs) may exhibit antibiofilm properties; however, more studies, including combinatorial therapy with antibiotics, are needed to explore their potential applications in clinical settings. This study aims to investigate the biofilm inhibition properties of glucosamine AuNPs in combination with meropenem against P. aeruginosa ATCC 9027 on the endotracheal tube. A biofilm inhibition assay of glucosamine AuNPs at 0.02 mg/mL, both singly and in combination with meropenem at 1 mg/mL, was carried out against P. aeruginosa ATCC 9027 on an endotracheal tube using the tissue culture plate method. Scanning electron microscopy was performed for visualization. Glucosamine AuNPs at 0.02 mg/mL combined with meropenem at 1 mg/mL showed greater biofilm inhibition (72%) on the endotracheal tube than glucosamine nanoparticles at 0.02 mg/mL alone (26%) (p = 0.001). The scanning electron microscopic visualization revealed that the untreated P. aeruginosa biofilm was denser than the glucosamine nanoparticles-treated biofilm, whether combined with meropenem or using glucosamine nanoparticles alone. The combination of glucosamine AuNPs and meropenem may have the synergistic effect of inhibiting biofilm production of P. aeruginosa on the endotracheal tubes of patients with mechanical ventilation. Conducting additional experiments to explore the impact of combining glucosamine-coated gold nanoparticles (AuNPs) with meropenem on the inhibition of biofilm production by clinical P. aeruginosa isolates would be beneficial.

Romanian Wild-Growing Chelidonium majus-An Emerging Approach to a Potential Antimicrobial Engineering Carrier System Based on AuNPs: In Vitro Investigation and Evaluation

Novel nanotechnology based on herbal products aspires to be a high-performing therapeutic platform. This study reports the development of an original engineering carrier system that jointly combines the pharmacological action of Chelidonium majus and AuNPs, with unique properties that ensure that the limitations imposed by low stability, toxicity, absorption, and targeted and prolonged release can be overcome. The metabolite profile of Romanian wild-grown Chelidonium majus contains a total of seventy-four phytochemicals belonging to eight secondary metabolite categories, including alkaloids, amino acids, phenolic acids, flavonoids, carotenoids, fatty acids, sterols, and miscellaneous others. In this study, various techniques (XRD, FTIR, SEM, DLS, and TG/DTG) were employed to investigate his new carrier system's morpho-structural and thermal properties. In vitro assays were conducted to evaluate the antioxidant potential and release profile. The results indicate 99.9% and 94.4% dissolution at different pH values for the CG-AuNPs carrier system and 93.5% and 85.26% for greater celandine at pH 4 and pH 7, respectively. Additionally, three in vitro antioxidant assays indicated an increase in antioxidant potential (flavonoid content 3.8%; FRAP assay 24.6%; and DPPH 24.4%) of the CG-AuNPs carrier system compared to the herb sample. The collective results reflect the system's promising perspective as a new efficient antimicrobial and anti-inflammatory candidate with versatile applications, ranging from target delivery systems, oral inflammation (periodontitis), and anti-age cosmetics to extending the shelf lives of products in the food industry.

A Nanoplatform Based on Pillar[5]arene Nanovalves for Combined Drug Delivery and Enhanced Antitumor Activity

Modern nanodrug delivery technologies offer new approaches in the fight against cancer. However, due to the heterogeneity of tumors and side effects of anticancer drugs, monotherapies are less effective. Herein, we report a novel pH and light dual-responsive nanodrug delivery platform. The platform was formed by sulfonate-modified gold nanoparticles loaded with the anticancer drugs doxorubicin (DOX) and glucose oxidase (GOx) and then covered by water-soluble pillar[5]arene as a nanovalve. The nanovalve formed by the host-guest interaction between pillar[5]arene and the sulfonic acid group grafted onto the gold nanoparticle increased the drug loading capacity of the nanoplatform and enabled sustained release of the drug in a simulated weakly acidic tumor environment. The released GOx can consume intracellular glucose, namely, starvation therapy, while the generated hydrogen peroxide can further kill tumor cells, complementing DOX chemotherapy. Gold nanoparticles have good photothermal conversion ability and can enhance the drugs release rate under specific wavelengths of light irradiation. The results of in vitro and in vivo experiments showed that this novel nanodrug delivery platform has good biocompatibility and better therapeutic efficacy relative to monotherapy. This study successfully developed a combined chemo/starvation therapy strategy with good tumor suppression, providing a new approach for cancer treatment.

Recent Advances in the Role of Different Nanoparticles in the Various Biosensors for the Detection of the Chikungunya Virus

Humans contract the Chikungunya virus (CHIKV), an alphavirus transmitted by mosquitoes that induces acute and chronic musculoskeletal discomfort and fever. Millions of cases of the disease have been attributed to CHIKV in the Indian Ocean region since 2004, and the virus has since spread to Europe, the Middle East, and the Pacific. The exponential proliferation of CHIKV in recent times underscores the critical nature of implementing preventative measures and exploring potential control strategies. The principal laboratory test employed to diagnose infection in serum samples collected over six days after the onset of symptoms is the detection of CHIKV or viral RNA. Although two commercially available real-time reverse transcription-polymerase chain reaction products exist, data on their validity are limited. A diagnostic instrument that is rapid, sensitive, specific, and cost-effective is, therefore an absolute necessity, particularly in developing nations. Biosensors have demonstrated considerable potential in the realm of pathogen detection. The rapid and sensitive detection of viruses has been facilitated by the development of numerous types of biosensors, including affinity-based nano-biosensors, graphene affinity-based biosensors, optical nano-biosensors, surface Plasmon Resonance-based optical nano-biosensors, and electrochemical nano-biosensors. Furthermore, the utilization of nanomaterials for signal extension, including but not limited to gold and silver nanoparticles, quantum dots, and iron oxide NPs, has enhanced the precision and sensitivity of biosensors. The developed innovative diagnostic method is time-efficient, precise, and economical; it can be implemented as a point-of-care device. The technique may be implemented in diagnostic laboratories and hospitals to identify patients infected with CHIKV. Throughout this article, we have examined a multitude of CHIKV nano-biosensors and their respective properties. Following a discussion of representative nanotechnologies for biosensors, numerous NPs-assisted CHIKV nano-biosensors are summarized in this article. As a result, we anticipate that this review will furnish a significant foundation for advancing innovative CHIKV nano-biosensors.

Anti-cancer effects of green synthesized gold nanoparticles using leaf extract of Annona muricata. L against squamous cell carcinoma cell line 15 through apoptotic pathway

Background

Oral cancer remains one of the most dreadful diseases in developing nations. Currently, there has been a rise in the prevalence of tongue squamous cell carcinoma (SCC), with a poor prognosis. The use of standard treatment approaches against oral cancer patients brings about several side effects. In recent years, nanomedicine has provided a versatile platform for developing new targeted therapeutic modalities. However, safety remains a concern in the synthesis of nanoparticles (NPs). Therefore, the present study aims to synthesize safer phytoconstituent-mediated gold NPs (AuNPs) utilizing leaf extracts of Annona muricata, where the biochemical components of the plant leaf act as the reducing and capping agents in the synthesis of NPs, and to evaluate its anti-cancer activity against SCC.

Materials and Methods

In this in vitro experimental study, AuNPs were synthesized through an effective, simple, and ecologically sound green synthesis method. After characterization of these synthesized AuNPs, in vitro assays such as 3-(4, 5-dimethylthiazole2-yl)-2, 5-biphenyl tetrazolium bromide, wound healing, and clonogenic assays were carried out to investigate the anti-cancer potential of green synthesized AuNPs in the human tongue SCC cell line (SCC-15), and the possible mechanism of action was evaluated through gene and protein expression analysis of Bax, Bcl-2, and p53 genes. The results were expressed as mean ± standard deviation using Statistical Package for Social Sciences (SPSS) 20.0 software and Student's t-test was performed for experimental data. P ≤0.05 were considered statistically significant.

Results

The in vitro assays demonstrated that the synthesized AuNPs are exhibiting anti-cancer activity by apoptosis of SCC-15 cells in a dose-dependent manner. Further, it also revealed a highly significant decrease in anti-apoptotic Bcl-2 gene expression, whereas pro-apoptotic genes p53 and Bax revealed a highly significant increase, which is statistically significant compared to the control (P < 0.05).

Conclusion

Our findings demonstrated that the AuNPs synthesized from A. muricata leaf extract could act as a novel anticancer agent, particularly against SCC, after further scrutiny.

Gold Nanoparticles in Neurological Diseases: A Review of Neuroprotection

This review explores the diverse applications of gold nanoparticles (AuNPs) in neurological diseases, with a specific focus on Alzheimer's disease (AD), Parkinson's disease (PD), and stroke. The introduction highlights the pivotal role of neuroinflammation in these disorders and introduces the unique properties of AuNPs. The review's core examines the mechanisms by which AuNPs exert neuroprotection and anti-neuro-inflammatory effects, elucidating various pathways through which they manifest these properties. The potential therapeutic applications of AuNPs in AD are discussed, shedding light on promising avenues for therapy. This review also explores the prospects of utilizing AuNPs in PD interventions, presenting a hopeful outlook for future treatments. Additionally, the review delves into the potential of AuNPs in providing neuroprotection after strokes, emphasizing their significance in mitigating cerebrovascular accidents' aftermath. Experimental findings from cellular and animal models are consolidated to provide a comprehensive overview of AuNPs' effectiveness, offering insights into their impact at both the cellular and in vivo levels. This review enhances our understanding of AuNPs' applications in neurological diseases and lays the groundwork for innovative therapeutic strategies in neurology.

Zebrafish Insights into Nanomaterial Toxicity: A Focused Exploration on Metallic, Metal Oxide, Semiconductor, and Mixed-Metal Nanoparticles

Nanomaterials are widely used in various fields, and ongoing research is focused on developing safe and sustainable nanomaterials. Using zebrafish as a model organism for studying the potentially toxic effects of nanomaterials highlights the importance of developing safe and sustainable nanomaterials. Studies conducted on nanomaterials and their toxicity and potential risks to human and environmental health are vital in biomedical sciences. In the present review, we discuss the potential toxicity of nanomaterials (inorganic and organic) and exposure risks based on size, shape, and concentration. The review further explores various types of nanomaterials and their impacts on zebrafish at different levels, indicating that exposure to nanomaterials can lead to developmental defects, changes in gene expressions, and various toxicities. The review also covers the importance of considering natural organic matter and chorion membranes in standardized nanotoxicity testing. While some nanomaterials are biologically compatible, metal and semiconductor nanomaterials that enter the water environment can increase toxicity to aquatic creatures and can potentially accumulate in the human body. Further investigations are necessary to assess the safety of nanomaterials and their impacts on the environment and human health.

Recent advances and clinical translation of liposomal delivery systems in cancer therapy

The limitations of conventional cancer treatment are driving the emergence and development of nanomedicines. Research in liposomal nanomedicine for cancer therapy is rapidly increasing, opening up new horizons for cancer treatment. Liposomal nanomedicine, which focuses on targeted drug delivery to improve the therapeutic effect of cancer while reducing damage to normal tissues and cells, has great potential in the field of cancer therapy. This review aims to clarify the advantages of liposomal delivery systems in cancer therapy. We describe the recent understanding of spatiotemporal fate of liposomes in the organism after different routes of drug administration. Meanwhile, various types of liposome-based drug delivery systems that exert their respective advantages in cancer therapy while reducing side effects were discussed. Moreover, the combination of liposomal agents with other therapies (such as photodynamic therapy and photothermal therapy) has demonstrated enhanced tumor-targeting efficiency and therapeutic efficacy. Finally, the opportunities and challenges faced by the field of liposome nanoformulations for entering the clinical treatment of cancer are highlighted.

Streptomyces monashensis MSK03-mediated synthesis of gold nanoparticles: characterization and antibacterial activity

Nanotechnology is a cutting-edge field with diverse applications, particularly in the utilization of gold nanoparticles (AuNPs) due to their stability and biocompatibility. AuNPs serve as pivotal components in medical applications, with a specific emphasis on their significant antibacterial efficacy. This study focuses on synthesizing AuNPs using the cell-free supernatant of Streptomyces monashensis MSK03, isolated from terrestrial soil in Thailand. The biosynthesis process involved utilizing the cell-free supernatant of S. monashensis MSK03 and hydrogen tetrachloroauric acid (HAuCl4) under controlled conditions of 37 °C and 200 rpm agitation. Characterization studies revealed spherical AuNPs with sizes ranging from 7.1 to 40.0 nm (average size: 23.2 ± 10.7 nm), as confirmed by TEM. UV-Vis spectroscopy indicated a localized surface plasmon resonance (LSPR) band at 545 nm, while XRD analysis confirmed a crystalline structure with characteristics of cubic lattice surfaces. The capping molecules on the surface of AuNPs carry a negative charge, indicated by a Zeta potential of -26.35 mV, and FTIR analysis identified functional groups involved in reduction and stabilization. XANES spectra further confirmed the successful reduction of Au3+ to Au0. Moreover, the synthesized AuNPs demonstrated antibacterial activity against drug-resistant strains of Pseudomonas aeruginosa and Acinetobacter baumannii. Interestingly, the AuNPs showed non-toxicity to Vero cell lines. These significant antibacterial properties of the produced nanoparticles mean they hold great promise as new antimicrobial treatments for tackling the increasing issue of antibiotic resistance.

Novel Organoid Culture System for Improved Safety Assessment of Nanomaterials

Over the past few decades, the increased application of nanomaterials has raised questions regarding their safety and possible toxic effects. Organoids have been suggested as promising tools, offering efficient assays for nanomaterial-induced toxicity evaluation. However, organoid systems have some limitations, such as size heterogeneity and poor penetration of nanoparticles because of the extracellular matrix, which is necessary for organoid culture. Here, we developed a novel system for the improved safety assessment of nanomaterials by establishing a 3D floating organoid paradigm. In addition to overcoming the limitations of two-dimensional systems including the lack of in vitro-in vivo cross-talk, our method provides multiple benefits as compared with conventional organoid systems that rely on an extracellular matrix for culture. Organoids cultured using our method exhibited relatively uniform sizing and structural integrity and were more conducive to the internalization of nanoparticles. Our floating culture system will accelerate the research and development of safe nanomaterials.

Clickable bisreactive small gold nanoclusters for preparing multifunctionalized nanomaterials: application to photouncaging of an anticancer molecule

In this study, we successfully synthesized a small-sized gold nanocluster (2 nm) coated with homogeneous tripeptides bearing azido and amino groups that enable facile multifunctionalizations. Using sodium phenoxide to reduce tetrachloroauric(iii) acid in the presence of the cysteine-containing tripeptide, we efficiently prepared the gold nanoclusters without damaging the azido group. We then utilized this clickable bisreactive nanocluster as a versatile platform for synthesizing multifunctionalized gold nanomaterials. The resulting nanoclusters were conjugated with an anticancer compound connected to an indolizine moiety for photoinduced uncaging, a photodynamic therapy agent acting as a photosensitizer for uncaging, and a cyclic RGD peptide. The cytotoxicity of the multifunctionalized gold nanoclusters was demonstrated through red light irradiation of human lung cancer-derived A549 cells treated with the synthesized nanomaterials. The significant cytotoxicity exhibited by the cells underscores the potential utility of this method in advanced cancer therapies.

Investigation of selective SERS enhancement mechanism of Au nanospheres and Au nanorods based on 2T2D-SERS correlation spectroscopy

The selective enhancement mechanism in surface-enhanced Raman scattering (SERS) is demonstrated. Two different types of single nanoparticles (Au nanosphere and Au nanorod) were used to investigate the role of the localized surface plasmon resonance (LSPR) in SERS spectra by using the two-trace two-dimensional (2T2D) correlation spectroscopy. The SERS intensities of three probe molecules, 4-mercaptobenzoic acid (4-MBA), 4-aminothiophenol (4-ATP), and 4-bromobenzenethiol (4-BBT), respectively, were enhanced but slightly different when adsorbed on Au nanospheres and Au nanorods. 2T2D correlation SERS spectra clearly showed that even with the same shape of Au nanoparticles, the main factors influencing the SERS enhancement can vary depending on the specific type of SERS tags used. Such subtle difference could not be clearly identified by the conventional spectral analysis. This result sheds light on potential applications of 2T2D correlation spectroscopy. For 4-MBA molecules, the a1 and b2 modes are mainly affected by the Au nanospheres and Au nanorods. For 4-ATP molecules, the a1 and b2 modes related to C-S stretching combined with C-C stretching band are mainly affected by Au nanorods and Au nanospheres. For 4-BBT molecules, the a1 and b2 modes of C-C (aromatic ring) stretching band are mainly affected by Au nanorods and Au nanospheres. This study offers valuable insights into the relationship between nanoparticle shape and SERS enhancement.

Harnessing the power of gold: advancements in anticancer gold complexes and their functionalized nanoparticles

Cancer poses a formidable challenge, necessitating improved treatment strategies. Metal-based drugs and nanotechnology offer new hope in this battle. Versatile gold complexes and functionalized gold nanoparticles exhibit unique properties like biologically inert behaviour, outstanding light absorption, and heat-conversion abilities. These nanoparticles can be finely tuned for drug delivery, enabling precise and targeted cancer therapy. Their exceptional drug-loading capacity and low toxicity, stemming from excellent stability, biocompatibility, and customizable shapes, make them a promising option for enhancing cancer treatment outcomes and improving diagnostic imaging. Leveraging these attributes, researchers can design more effective and targeted cancer therapeutics. The potential of functionalized gold nanoparticles to advance cancer treatment and diagnostics holds a promising avenue for further exploration and development in the fight against cancer. This review article delves into the finely tuned attributes of functionalized gold nanoparticles, unveiling their potential for application in drug delivery for precise and targeted cancer therapy.

Biophysical study of DC electric field induced stable formation of albumin-gold nanoparticles corona and curcumin binding

Targeted drug delivery (TDD) is a method of delivering optimum concentrations of pharmaceutical substances in the tissue to achieve the desired therapeutic effect. Hence, TDD systems are considered as an emerging strategy to deliver the drug at the specific site of the tissues/cells. The nanoparticle-protein corona as a drug delivery vehicle has demonstrated immense benefits including potential theragnostic, improved pharmacodynamics and targeted drug delivery. In the present investigation, efforts have been to establish stable and functionalized Bovine serum albumin-gold nanoparticle (BSA-GNP) corona (conjugates) using a Direct Current (DC) electric field. With the application of DC electric field (DEF) across the BSA-GNP solution, the formation of BSA-GNP corona/conjugate takes place which was characterized using various biophysical techniques such a Dynamic Light Scattering (DLS), UV Visible spectroscopy, Fluorescence spectroscopy, electrophoresis, etc. Furthermore, the DEF engineered BSA-GNP corona was loaded/interacted with curcumin (CUR). The size of the BSA-GNP corona was increased with increasing DC voltage (5-30 V) at constant concentration of BSA. The strong and stable binding of curcumin with BSA-GNP corona was revealed by the techniques used in the investigation; however, binding affinity of CUR was decreased for 30 V DEF exposed BSA-GNP conjugate. The biocompatible experimental data confirms the nontoxic nature of BSA-GNP corona. This investigation adds a new and novel physical method for the preparation of protein-nanoparticle corona for various applications including drug delivery.

Green biosynthesis of bimetallic selenium-gold nanoparticles using Pluchea indica leaves and their biological applications

Increasing bacterial resistance and the negative impact of currently used antibacterial agents have produced the need for novel antibacterial agents and anticancer drugs. In this regard, nanotechnology could provide safer and more efficient therapeutic agents. The main methods for nanoparticle production are chemical and physical approaches that are often costly and environmentally unsafe. In the current study, Pluchea indica leaf extract was used for the biosynthesis of bimetallic selenium-gold nanoparticles (Se-Au BNPs) for the first time. Phytochemical examinations revealed that P. indica leaf extract includes 90.25 mg/g dry weight (DW) phenolics, 275.53 mg/g DW flavonoids, and 26.45 mg/g DW tannins. X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) techniques were employed to characterize Se-Au BNPs. Based on UV-vis spectra, the absorbance of Se-Au BNPs peaked at 238 and 374 nm. In SEM imaging, Se-Au BNPs emerged as bright particles, and both Au and Se were uniformly distributed throughout the P. indica leaf extract. XRD analysis revealed that the average size of Se-Au BNPs was 45.97 nm. The Se-Au BNPs showed antibacterial properties against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis, with minimum inhibitory concentrations (MICs) of 31.25, 15.62, 31.25, and 3.9 μg/mL, respectively. Surprisingly, a cytotoxicity assay revealed that the IC50 value toward the Wi 38 normal cell line was 116.8 μg/mL, implying that all of the MICs described above could be used safely. More importantly, Se-Au BNPs have shown higher anticancer efficacy against human breast cancer cells (MCF7), with an IC50 value of 13.77 μg/mL. In conclusion, this paper is the first to provide data on the effective utilization of P. indica leaf extract in the biosynthesis of biologically active Se-Au BNPs.

Microbubble-assisted ultrasound for inner ear drug delivery

Treating pathologies of the inner ear is a major challenge. To date, a wide range of procedures exists for administering therapeutic agents to the inner ear, with varying degrees of success. The key is to deliver therapeutics in a way that is minimally invasive, effective, long-lasting, and without adverse effects on vestibular and cochlear function. Microbubble-assisted ultrasound ("sonoporation") is a promising new modality that can be adapted to the inner ear. Combining ultrasound technology with microbubbles in the middle ear can increase the permeability of the round window, enabling therapeutic agents to be delivered safely and effectively to the inner ear in a targeted manner. As such, sonoporation is a promising new approach to treat hearing loss and vertigo. This review summarizes all studies on the delivery of therapeutic molecules to the inner ear using sonoporation.

Applications of Green Synthesized Metal Nanoparticles - a Review

Green nanotechnology is an emerging field of science that focuses on the production of nanoparticles by living cells through biological pathways. This topic plays an extremely imperative responsibility in various fields, including pharmaceuticals, nuclear energy, fuel and energy, electronics, and bioengineering. Biological processes by green synthesis tools are more suitable to develop nanoparticles ranging from 1 to 100 nm compared to other related methods, owing to their safety, eco-friendliness, non-toxicity, and cost-effectiveness. In particular, the metal nanoparticles are synthesized by top-down and bottom-up approaches through various techniques like physical, chemical, and biological methods. Their characterization is very vital and the confirmation of nanoparticle traits is done by various instrumentation analyses such as UV-Vis spectrophotometry (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic force microscopy (AFM), annular dark-field imaging (HAADF), and intracranial pressure (ICP). In this review, we provide especially information on green synthesized metal nanoparticles, which are helpful to improve biomedical and environmental applications. In particular, the methods and conditions of plant-based synthesis, characterization techniques, and applications of green silver, gold, iron, selenium, and copper nanoparticles are overviewed.

Nanomaterials-combined methacrylated gelatin hydrogels (GelMA) for cardiac tissue constructs

Among non-communicable diseases, cardiovascular diseases are the most prevalent, accounting for approximately 17 million deaths per year. Despite conventional treatment, cardiac tissue engineering emerges as a potential alternative for the advancement and treatment of these patients, using biomaterials to replace or repair cardiac tissues. Among these materials, gelatin in its methacrylated form (GelMA) is a biodegradable and biocompatible polymer with adjustable biophysical properties. Furthermore, gelatin has the ability to replace and perform collagen-like functions for cell development in vitro. The interest in using GelMA hydrogels combined with nanomaterials is increasingly growing to promote the responsiveness to external stimuli and improve certain properties of these hydrogels by exploring the incorporation of nanomaterials into these hydrogels to serve as electrical signaling conductive elements. This review highlights the applications of electrically conductive nanomaterials associated with GelMA hydrogels for the development of structures for cardiac tissue engineering, by focusing on studies that report the combination of GelMA with nanomaterials, such as gold and carbon derivatives (carbon nanotubes and graphene), in addition to the possibility of applying these materials in 3D tissue engineering, developing new possibilities for cardiac studies.

Assessment of reproductive toxicity of gold nanoparticles and its reversibility in male albino rats

Nanotechnology has become a trending area in science all over the world. Although gold nanoparticles (AuNPs) have been utilized widely in biomedical fields, potential toxicities may arise from their interactions with biological systems. The current study aimed at evaluating the toxic effects of AuNPs on the reproductive system of adult male albino rats and assessing the recovery probability. In this study, AuNPs (13 ± 4 nm in diameter) were synthesized, and the experimental work was conducted on 60 adult male albino rats divided into the following groups: control group (received deionized water daily intraperitoneally (IP) for 28 days), test group, and withdrawal groups I and II (received 570 μg/kg of 13 ± 4 nm AuNPs daily IP for 28 days). Withdrawal groups I and II were left for another 30 and 60 days without sacrification, respectively. The test group showed significant decreases in final body and absolute testicular weights, testosterone hormone level, sperm count and motility, and spermatogenesis score, as well as significant increase in the percentage of sperms of abnormal morphology compared to the control group, associated with significant light and electron microscopic histopathological changes. Partial improvement of all studied reproductive parameters was detected after one month of withdrawal in withdrawal group I, and significant improvement and reversibility of all these parameters were reported after two months of withdrawal in withdrawal group II. So, AuNPs induce male reproductive toxicity, which partially improves after one month of withdrawal and significantly improves and reverses after two months of withdrawal.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43188-023-00203-2.

Investigating the ecological implications of nanomaterials: Unveiling plants' notable responses to nano-pollution

The rapid advancement of nanotechnology has led to unprecedented innovations; however, it is crucial to analyze its environmental impacts carefully. This review thoroughly examines the complex relationship between plants and nanomaterials, highlighting their significant impact on ecological sustainability and ecosystem well-being. This study investigated the response of plants to nano-pollution stress, revealing the complex regulation of defense-related genes and proteins, and highlighting the sophisticated defense mechanisms in nature. Phytohormones play a crucial role in the complex molecular communication network that regulates plant responses to exposure to nanomaterials. The interaction between plants and nano-pollution influences plants' complex defense strategies. This reveals the interconnectedness of systems of nature. Nevertheless, these findings have implications beyond the plant domain. The incorporation of hyperaccumulator plants into pollution mitigation strategies has the potential to create more environmentally sustainable urban landscapes and improve overall environmental resilience. By utilizing these exceptional plants, we can create a future in which cities serve as centers of both innovation and ecological balance. Further investigation is necessary to explore the long-term presence of nanoparticles in the environment, their ability to induce genetic changes in plants over multiple generations, and their overall impact on ecosystems. In conclusion, this review summarizes significant scientific discoveries with broad implications beyond the confines of laboratories. This highlights the importance of understanding the interactions between plants and nanomaterials within the wider scope of environmental health. By considering these insights, we initiated a path towards the responsible utilization of nanomaterials, environmentally friendly management of pollution, and interdisciplinary exploration. We have the responsibility to balance scientific advancement and environmental preservation to create a sustainable future that combines nature's wisdom with human innovation.

Plasmonic Magnesium Nanoparticles Are Efficient Nanoheaters

Understanding and guiding light at the nanoscale can significantly impact society, for instance, by facilitating the development of efficient, sustainable, and/or cost-effective technologies. One emergent branch of nanotechnology exploits the conversion of light into heat, where heat is subsequently harnessed for various applications including therapeutics, heat-driven chemistries, and solar heating. Gold nanoparticles are overwhelmingly the most common material for plasmon-assisted photothermal applications; yet magnesium nanoparticles present a compelling alternative due to their low cost and superior biocompatibility. Herein, we measured the heat generated and quantified the photothermal efficiency of the gold and magnesium nanoparticle suspensions. Photothermal transduction experiments and optical and thermal simulations of different sizes and shapes of gold and magnesium nanoparticles showed that magnesium is more efficient at converting light into heat compared to gold at near-infrared wavelengths, thus demonstrating that magnesium nanoparticles are a promising new class of inexpensive, biodegradable photothermal platforms.

Enhancement of cell membrane permeability by using charged nanoparticles and a weak external electric field

Because the cell membrane is the main barrier of intracellular delivery, it is important to facilitate and control the translocation of extracellular compounds across it. Our earlier molecular dynamics simulations suggested that charged nanoparticles under a weak external electric field can enhance the permeability of the cell membrane without disrupting it. However, this membrane permeabilization approach has not been tested experimentally. This study investigated the membrane crossing of a model compound (dextran with a Mw of 3000-5000) using charged nanoparticles and a weak external electric field. A model bilayer lipid membrane was prepared by using a droplet contact method. The permeability of the membrane was evaluated using the electrophysiological technique. Even when the applied electric field was below the critical strength for membrane breakdown, dextran was able to cross the membrane without causing membrane breakdown. These results indicate that adding nanomaterials under a weak electric field may enhance the translocation of delivery compounds across the cell membrane with less damage, suggesting a new strategy for intracellular delivery systems.

Adsorption and Molecular Display of a Redox-Active Protein on Gold Nanoparticle Surfaces

Engineered gold nanoparticles (AuNPs) have great potential in many applications due to their tunable optical properties, facile synthesis, and surface functionalization via thiol chemistry. When exposed to a biological environment, NPs are coated with a protein corona that can alter the NPs' biological identity but can also affect the proteins' structures and functions. Protein disulfide isomerase (PDI) is an abundant protein responsible for the disulfide formation and isomerization that contribute to overall cell redox homeostasis and signaling. Given that AuNPs are widely employed in nanomedicine and PDI plays a functional role in various diseases, the interactions between oxidized (oPDI) and reduced (rPDI) with 50 nm citrate-coated AuNPs (AuNPs) are examined in this study using various techniques. Upon incubation, PDI adsorbs to the AuNP surface, which leads to a reduction in its enzymatic activity despite limited changes in secondary structures. Partial enzymatic digestion followed by mass spectrometry analysis shows that orientation of PDI on the NP surface is dependent on both its oxidation state and the PDI:AuNP incubation ratios.

Shape control of Au nanostructures using peptides for biotechnological applications

Metallic gold (Au) nanostructures have attracted attentions in various fields of materials science and electrical science in terms of catalysts, sensing systems, photonic devices, and drug delivery systems because of their characteristic physical, chemical, and biocompatible properties. Recently, Au nanostructures with near-infrared light absorbing properties have shown potential for applications such as biological imaging and thermotherapy in biotechnological fields. However, fabrication of Au nanostructures with complex shapes often requires the use of highly biotoxic substances such as surfactants and reducing agents. Peptides are promising compounds for controlling the shape of Au nanostructures by mineralization with several advantages for this purpose. In this highlight, we focus on the shapes with respect to the fabrication of Au nanostructures using biocompatible peptides. We classify the peptides that form Au nanostructures into three broad categories: those that bind Au ions, those that reduce Au ions, and those that control the direction of Au crystal growth. Then, we briefly summarize the correlations between peptide sequences and their roles, and propose future strategies for fabricating Au nanostructures using peptides for biotechnological applications.

Curcumin-functionalized gold nanoparticles attenuate AAPH-induced acute cardiotoxicity via reduction of lipid peroxidation and modulation of antioxidant parameters in a chicken embryo model

Gold nanoparticles (AuNPs) have gained considerable attention due to their biocompatibility, customizable optical properties and ease of synthesis. In this study, an environmentally friendly method was used for synthesize curcumin-functionalized AuNPs (AuNP-C). AuNP-C exhibited a spherical shape, uniformity, and an average diameter of 6 nm. The in vitro antioxidant activity was analyzed, and cytotoxicity properties of AuNP-C were assessed in fibroblast and macrophage cells. Additionally, the effects of AuNP-C on oxidative stress in chicken embryo liver and hearts were investigated. AuNP-C demonstrated potent free radical scavenging properties without exhibiting cytotoxicity and hepatotoxicity effects. Administration of 300 µg/mL of AuNP-C in chicken embryos, subjected to oxidative damage induced by 2,2'-azobis(2-amidinopropane) dihydrochloride, significantly reduced lipid peroxidation and reactive oxygen species levels in the cardiac tissue. Moreover, the activities of cardiac superoxide dismutase, catalase, and glutathione reductase were restored, accompanied by an increase in overall antioxidant capacity. Furthermore, at higher concentrations, AuNP-C normalized the reduced glutathione content. AuNP-C preserved the normal structure of blood vessels; however, it resulted in an increase in protein carbonylation. This study provides initial evidence for the modulation of antioxidant defense mechanisms by green-synthesized AuNPs and underscores the importance of investigating the in vivo safety of phytoantioxidant-functionalized nanoparticles.

Functionalized Gold Nanoparticles Suppress the Proliferation of Human Lung Alveolar Adenocarcinoma Cells by Deubiquitinating Enzymes Inhibition

Functionalized gold nanoparticles (AuNPs) are widely used in therapeutic applications, but little is known regarding the impact of their surface functionalization in the process of toxicity against cancer cells. This study investigates the anticancer effects of 5 nm spherical AuNPs functionalized with tannate, citrate, and PVP on deubiquitinating enzymes (DUBs) in human lung alveolar adenocarcinoma (A549) cells. Our findings show that functionalized AuNPs reduce the cell viability in a concentration- and time-dependent manner as measured by modified lactate dehydrogenase (mLDH) and 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assays. An increased generation of intracellular reactive oxygen species (ROS) and depletion of glutathione (GSH/GSSG) ratio was observed with the highest AuNP concentration of 10 μg/mL. The expression of DUBs such as ubiquitin specific proteases (USP7, USP8, and USP10) was slightly inhibited when treated with concentrations above 2.5 μg/mL. Moreover, functionalized AuNPs showed an inhibitory effect on protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) and wingless-related integration site (Wnt) signaling proteins, and this could further trigger mitochondrial related-apoptosis by the upregulation of caspase-3, caspase-9, and PARP in A549 cells. Furthermore, our study shows a mechanistic understanding of how functionalized AuNPs inhibit the DUBs, consequently suppressing cell proliferation, and can be modulated as an approach toward anticancer therapy. The study also warrants the need for future work to investigate the effect of functionalized AuNPs on DUB on other cancer cell lines both in vitro and in vivo.

A structure-activity approach towards the toxicity assessment of multicomponent metal oxide nanomaterials

The increase of human and environmental exposure to engineered nanomaterials (ENMs) due to the emergence of nanotechnology has raised concerns over their safety. The challenging nature of in vivo and in vitro toxicity assessment methods for ENMs, has led to emerging in silico techniques for ENM toxicity assessment, such as structure-activity relationship (SAR) models. Although such approaches have been extensively developed for the case of single-component nanomaterials, the case of multicomponent nanomaterials (MCNMs) has not been thoroughly addressed. In this paper, we present a SAR approach for the case metal and metal oxide MCNMs. The developed SAR framework is built using a dataset of 796 individual toxicity measurements for 340 different MCNMs, towards human cells, mammalian cells, and bacteria. The novelty of the approach lies in the multicomponent nature of the nanomaterials, as well as the size, diversity and heterogeneous nature of the dataset used. Furthermore, the approach used to calculate descriptors for surface loaded MCNMs, and the mechanistic insight provided by the model results can assist the understanding of MCNM toxicity. The developed models are able to correctly predict the toxic class of the MCNMs in the heterogeneous dataset, towards a wide range of human cells, mammalian cells and bacteria. Using the abovementioned approach, the principal toxicity pathways and mechanisms are identified, allowing a more holistic understanding of metal oxide MCNM toxicity.

Shape-Driven Response of Gold Nanoparticles to X-rays

Radiotherapy (RT) involves delivering X-ray beams to the tumor site to trigger DNA damage. In this approach, it is fundamental to preserve healthy cells and to confine the X-ray beam only to the malignant cells. The integration of gold nanoparticles (AuNPs) in the X-ray methodology could be considered a powerful tool to improve the efficacy of RT. Indeed, AuNPs have proven to be excellent allies in contrasting tumor pathology upon RT due to their high photoelectric absorption coefficient and unique physiochemical properties. However, an analysis of their physical and morphological reaction to X-ray exposure is necessary to fully understand the AuNPs' behavior upon irradiation before treating the cells, since there are currently no studies on the evaluation of potential NP morphological changes upon specific irradiations. In this work, we synthesized two differently shaped AuNPs adopting two different techniques to achieve either spherical or star-shaped AuNPs. The spherical AuNPs were obtained with the Turkevich-Frens method, while the star-shaped AuNPs (AuNSs) involved a seed-mediated approach. We then characterized all AuNPs with Transmission Electron Microscopy (TEM), Uv-Vis spectroscopy, Dynamic Light Scattering (DLS), zeta potential and Fourier Transform Infrared (FTIR) spectroscopy. The next step involved the treatment of AuNPs with two different doses of X-radiation commonly used in RT, namely 1.8 Gy and 2 Gy, respectively. Following the X-rays' exposure, the AuNPs were further characterized to investigate their possible physicochemical and morphological alterations induced with the X-rays. We found that AuNPs do not undergo any alteration, concluding that they can be safely used in RT treatments. Lastly, the actin rearrangements of THP-1 monocytes treated with AuNPs were also assessed in terms of coherency. This is a key proof to evaluate the possible activation of an immune response, which still represents a big limitation for the clinical translation of NPs.

Using Sparfloxacin-Capped Gold Nanoparticles to Modify a Screen-Printed Carbon Electrode Sensor for Ethanol Determination

Alcohol is a dangerous substance causing global mortality and health issues, including mental health problems. Regular alcohol consumption can lead to depression, anxiety, cognitive decline, and increased risk of alcohol-related disorders. Thus, monitoring ethanol levels in biological samples could contribute to maintaining good health. Herein, we developed an electrochemical sensor for the determination of ethanol in human salivary samples. Initially, the tetra-chloroauric acid (HAuCl4) was chemically reduced using sparfloxacin (Sp) which also served as a stabilizing agent for the gold nanoparticles (AuNPs). As-prepared Sp-AuNPs were comprehensively characterized and confirmed by UV-visible spectroscopy, X-ray diffraction, field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), and elemental mapping analysis. The average particle size (~25 nm) and surface charge (negative) of Sp-AuNPs were determined by using dynamic light scattering (DLS) and Zeta potential measurements. An activated screen-printed carbon electrode (A-SPE) was modified using Sp-AuNPs dispersion, which exhibited greater electrocatalytic activity and sensitivity for ethanol (EtOH) oxidation in 0.1 M sodium hydroxide (NaOH) as studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). DPV showed a linear response for EtOH from 25 µM to 350 µM with the lowest limit of detection (LOD) of 0.55 µM. Reproducibility and repeatability studies revealed that the Sp-AuNPs/A-SPEs were highly stable and very sensitive to EtOH detection. Additionally, the successful electrochemical determination of EtOH in a saliva sample was carried out. The recovery rate of EtOH spiked in the saliva sample was found to be 99.6%. Thus, the incorporation of Sp-AuNPs within sensors could provide new possibilities in the development of ethanol sensors with an improved level of precision and accuracy.

Impact of Surface Charge-Tailored Gold Nanorods for Selective Targeting of Mitochondria in Breast Cancer Cells Using Photodynamic Therapy

Herein, the impact of surface charge tailored of gold nanorods (GNRs) on breast cancer cells (MCF-7 and MDA-MB-231) upon conjugation with triphenylphosphonium (TPP) for improved photodynamic therapy (PDT) targeting mitochondria was studied. The salient features of the study are as follows: (i) positive (CTAB@GNRs) and negative (PSS-CTAB@GNRs) surface-charged gold nanorods were developed and characterized; (ii) the mitochondrial targeting efficiency of gold nanorods was improved by conjugating TPP molecules; (iii) the conjugated nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) were evaluated for PDT in the presence of photosensitizer (PS), 5-aminolevulinic acid (5-ALA) in breast cancer cells; (iv) both nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) induce apoptosis, damage DNA, generate reactive oxygen species, and decrease mitochondrial membrane potential upon 5-ALA-based PDT; and (v) 5-ALA-PDT of two nanoprobes (TPP-CTAB@GNRs and TPP-PSS-CTAB@GNRs) impact cell signaling (PI3K/AKT) pathway by upregulating proapoptotic genes and proteins. Based on the results, we confirm that the positively charged (rapid) nanoprobes are more advantageous than their negatively (slow) charged nanoprobes. However, depending on the kind and degree of cancer, both nanoprobes can serve as efficient agents for delivering anticancer therapy.

Photothermal Effect of Gold Nanoparticles as a Nanomedicine for Diagnosis and Therapeutics

Gold nanoparticles (AuNPs) have received great attention for various medical applications due to their unique physicochemical properties. AuNPs with tunable optical properties in the visible and near-infrared regions have been utilized in a variety of applications such as in vitro diagnostics, in vivo imaging, and therapeutics. Among the applications, this review will pay more attention to recent developments in diagnostic and therapeutic applications based on the photothermal (PT) effect of AuNPs. In particular, the PT effect of AuNPs has played an important role in medical applications utilizing light, such as photoacoustic imaging, photon polymerase chain reaction (PCR), and hyperthermia therapy. First, we discuss the fundamentals of the optical properties in detail to understand the background of the PT effect of AuNPs. For diagnostic applications, the ability of AuNPs to efficiently convert absorbed light energy into heat to generate enhanced acoustic waves can lead to significant enhancements in photoacoustic signal intensity. Integration of the PT effect of AuNPs with PCR may open new opportunities for technological innovation called photonic PCR, where light is used to enable fast and accurate temperature cycling for DNA amplification. Additionally, beyond the existing thermotherapy of AuNPs, the PT effect of AuNPs can be further applied to cancer immunotherapy. Controlled PT damage to cancer cells triggers an immune response, which is useful for obtaining better outcomes in combination with immune checkpoint inhibitors or vaccines. Therefore, this review examines applications to nanomedicine based on the PT effect among the unique optical properties of AuNPs, understands the basic principles, the advantages and disadvantages of each technology, and understands the importance of a multidisciplinary approach. Based on this, it is expected that it will help understand the current status and development direction of new nanoparticle-based disease diagnosis methods and treatment methods, and we hope that it will inspire the development of new innovative technologies.

Honey gold nanoparticles attenuate the secretion of IL-6 by LPS-activated macrophages

Interleukin-6 (IL-6) is a pleiotropic cytokine that coordinates host immune responses to infection. Though essential to the acute phase response, prolonged IL-6-mediated recruitment of mononuclear cells has been implicated in chronic inflammatory diseases such as rheumatoid arthritis, psoriasis, and Crohn's disease. Accordingly, identifying novel therapeutics that diminish circulating IL-6 levels could benefit individuals suffering from chronic inflammation. In immunocompetent hosts, bacterial lipopolysaccharide (LPS) recognition by toll-like receptor 4 (TLR4) activates the transcription factor NF-κB, driving macrophage production of IL-6. Interestingly, both citrate-stabilized and 'green' synthesized gold nanoparticles (AuNPs) have been shown to modulate the cytokine responses of LPS-activated macrophages. Here we demonstrate that AuNPs, synthesized with commercial and locally sourced honey, downregulate LPS-induced macrophage secretion of IL-6. Compared to LPS-only controls, inhibition of IL-6 levels was observed for all three types of honey AuNPs. The effect was likely driven by honey AuNP-mediated perturbation of the TLR4/NF-κB signaling pathway, as evidenced by a reduction in the phosphorylation of IκB. Further investigation into the anti-inflammatory properties of honey AuNPs may yield novel therapeutics for the treatment of chronic inflammation.

High-Throughput Single-Cell Analysis of Nanoparticle-Cell Interactions

Understanding nanoparticle-cell interactions at single-nanoparticle and single-cell resolutions is crucial to improving the design of next-generation nanoparticles for safer, more effective, and more efficient applications in nanomedicine. This review focuses on recent advances in the continuous high-throughput analysis of nanoparticle-cell interactions at the single-cell level. We highlight and discuss the current trends in continual flow high-throughput methods for analyzing single cells, such as advanced flow cytometry techniques and inductively coupled plasma mass spectrometry methods, as well as their intersection in the form of mass cytometry. This review further discusses the challenges and opportunities with current single-cell analysis approaches and provides proposed directions for innovation in the high-throughput analysis of nanoparticle-cell interactions.

Exploring the potential of metal and metal oxide nanomaterials for sustainable water and wastewater treatment: A review of their antimicrobial properties

Metallic nanoparticles (NPs) are of particular interest as antimicrobial agents in water and wastewater treatment due to their broad suppressive range against bacteria, viruses, and fungi commonly found in these environments. This review explores the potential of different types of metallic NPs, including zinc oxide, gold, copper oxide, and titanium oxide, for use as effective antimicrobial agents in water and wastewater treatment. This is due to the fact that metallic NPs possess a broad suppressive range against bacteria, viruses, as well as fungus. In addition to that, NPs are becoming an increasingly popular alternative to antibiotics for treating bacterial infections. Despite the fact that most research has been focused on silver NPs because of the antibacterial qualities that are known to be associated with them, curiosity about other metallic NPs as potential antimicrobial agents has been growing. Zinc oxide, gold, copper oxide, and titanium oxide NPs are included in this category since it has been demonstrated that these elements have antibacterial properties. Inducing oxidative stress, damage to the cellular membranes, and breakdowns throughout the protein and DNA chains are some of the ways that metallic NPs can have an influence on microbial cells. The purpose of this review was to engage in an in-depth conversation about the current state of the art regarding the utilization of the most important categories of metallic NPs that are used as antimicrobial agents. Several approaches for the synthesis of metal-based NPs were reviewed, including physical and chemical methods as well as "green synthesis" approaches, which are synthesis procedures that do not involve the employment of any chemical agents. Moreover, additional pharmacokinetics, physicochemical properties, and the toxicological hazard associated with the application of silver NPs as antimicrobial agents were discussed.

Gold nanoparticles attenuate the interferon-γ induced SOCS1 expression and activation of NF-κB p65/50 activity via modulation of microRNA-155-5p in triple-negative breast cancer cells

Objective

Triple-negative breast cancer (TNBC) is a very aggressive form of cancer that grows and spreads very fast and generally relapses. Therapeutic options of TNBC are limited and still need to be explored completely. Gold nanoparticles conjugated with citrate (citrate-AuNPs) are reported to have anticancer potential; however, their role in regulating microRNAs (miRNAs) in TNBC has never been investigated. This study investigated the potential of citrate-AuNPs against tumorigenic inflammation via modulation of miRNAs in TNBC cells.

Methods

Gold nanoparticles were chemically synthesized using the trisodium-citrate method and were characterized by UV-Vis spectrophotometry and dynamic light scattering studies. Targetscan bioinformatics was used to analyze miRNA target genes. Levels of miRNA and mRNA were quantified using TaqMan assays. The pairing of miRNA in 3'untranslated region (3'UTR) of mRNA was validated by luciferase reporter clone, containing the entire 3'UTR of mRNA, and findings were further re-validated via transfection with miRNA inhibitors.

Results

Newly synthesized citrate-AuNPs were highly stable, with a mean size was 28.3 nm. The data determined that hsa-miR155-5p is a direct regulator of SOCS1 (suppressor-of-cytokine-signaling) expression and citrate-AuNPs inhibits SOCS1 mRNA/protein expression via modulating hsa-miR155-5p expression. Transfection of TNBC MDA-MB-231 cells with anti-miR155-5p markedly increased SOCS1 expression (p<0.001), while citrate-AuNPs treatment significantly inhibited anti-miR155-5p transfection-induced SOCS1 expression (p<0.05). These findings were validated by IFN-γ-stimulated MDA-MB-231 cells. Moreover, the data also determined that citrate-AuNPs also inhibit IFN-γ-induced NF-κB p65/p50 activation in MDA-MB-231 cells transfected with anti-hsa-miR155-5p.

Conclusion

Newly generated citrate-AuNPs were stable and non-toxic to TNBC cells. Citrate-AuNPs inhibit IFN-γ-induced SOCS1 mRNA/protein expression and deactivate NF-κB p65/50 activity via negative regulation of hsa-miR155-5p. These novel pharmacological actions of citrate-AuNPs on IFN-γ-stimulated TNBC cells provide insights that AuNPs inhibit IFN-γ induced inflammation in TNBC cells by modulating the expression of microRNAs.

Exposure to High Dosage of Gold Nanoparticles Accelerates Growth Rate by Modulating Ribosomal Protein Expression

Gold nanoparticles (AuNPs) have been utilized in various biomedical applications including diagnostics and drug delivery. However, the cellular and metabolic responses of cells to these particles remain poorly characterized. In this study, we used bacteria (Escherichia coli and Bacillus subtilis) and a fungus (Saccharomyces cerevisiae) as model organisms to investigate the cellular and metabolic effects of exposure to different concentrations of citrate-capped spherical AuNPs with diameters of 5 and 10 nm. In different growth media, the synthesized AuNPs displayed stability and microorganisms exhibited uniform levels of uptake. Exposure to a high concentration of AuNPs (1012 particles) resulted in a reduced cell division time and a 2-fold increase in cell density in both bacteria and fungus. The exposed cells exhibited a decrease in average cell size and an increase in the expression of FtsZ protein (cell division marker), further supporting an accelerated growth rate. Notably, exposure to such a high concentration of AuNPs did not induce DNA damage, envelope stress, or a general stress response in bacteria. Differential whole proteome analysis revealed modulation of ribosomal protein expression upon exposure to AuNPs in both E. coli and S. cerevisiae. Interestingly, the accelerated growth observed upon exposure to AuNPs was sensitive to sub-minimum inhibitory concentration (sub-MIC) concentration of drugs that specifically target ribosome assembly and recycling. Based upon these findings, we hypothesize that exposure to high concentrations of AuNPs induces stress on the translation machinery. This leads to an increase in the protein synthesis rate by modulating ribosome assembly, which results in the rapid proliferation of cells.