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

Proteomic analysis of Trichoderma harzianum secretome and their role in the biosynthesis of zinc/iron oxide nanoparticles

The fungal green synthesis of nanoparticles (NPs) has gained great interest since it is a cost-effective and easy handling method. The process is simple because fungi secrete metabolites and proteins capable of reducing metal salts in aqueous solution, however the mechanism remains largely unknown. The aim of this study was to analyze the secretome of a Trichoderma harzianum strain during the mycobiosynthesis process of zinc and iron nanoparticles. Different profiles of proteins secreted by the fungus grown in the culture media or in the aqueous filtrate were observed through SDS‒PAGE and LC‒MS/MS analysis identifying 99 and 304 proteins, respectively. Particularly, in the aqueous filtrate proteins of metabolic processes and stress response mainly oxidoreductases, were identified. Successfully, ZnO and FeO NPs were synthesized and characterized by transmission electron microscopy, energy dispersive X-ray spectroscopy, dynamic light scattering, thermogravimetric, and FTIR analysis. FTIR revealed organic compounds in nanoparticles acting as probably capping agents. This research is the first report in which a proteomic analysis identifies multiple enzymes involved in the biogenic process of NP biosynthesis from T. harzianum, and its role is clearly demonstrated by the formation of zincite and magnetite nanoparticles.

Eco-friendly synthesis of gold nanoparticles via tangerine peel extract: Unveiling their multifaceted biological and catalytic potentials

Recent advancements in nanoscience underscore the transformative potential of nanomaterials in environmental and biological applications. In this study, we synthesized gold nanoparticles (Au@TPE NPs) using an eco-friendly and cost-effective approach, leveraging tangerine peel extract as both a capping and reducing agent. This method presents a sustainable alternative to traditional chemical agents. We optimized synthesis parameters, including time (5, 30, 60, and 90 min), temperature (25, 40, and 60 °C), and gold concentration (5, 10, 15, and 20 mM) to refine the nanoparticles size and morphology. Characterization via UV-Vis, XRD, FT-IR, EDAX, FESEM, and TEM revealed that nanoparticles synthesized at 40 °C and 15 mM gold concentration exhibited an optimal size (∼26 ± 5 nm) and a spherical shape. The Au@TPE NPs demonstrated antibacterial activity against both Gram-positive and Gram-negative bacteria, with minimum inhibitory concentrations (MIC) of 31.25 μg/ml for Klebsiella pneumoniae and Escherichia coli, and 62.5 μg/ml for Pseudomonas aeruginosa. Notably, they also exhibited antifungal activity against Candida albicans and demonstrated 92.7 % antioxidant activity in a DPPH scavenging assay at 250 μg/ml. Photocatalytic tests revealed that the nanoparticles effectively degraded methyl orange and rhodamine B, achieving 88.6 % and 93.2 % degradation under UV light, respectively, and 67.3 % and 74.1 % degradation under sunlight. These promising biological and catalytic properties suggest significant potential for diverse applications.

Effect of surface-engineered AuNPs on gene expression, bacterial interaction, protein denaturation, and toxicology assay: an in vitro and in vivo model

We investigated the in vitro and in vivo uses of pamoic acid functionalized gold nanoparticles (PA@AuNPs), with a focus on determining their safety and potential toxicity in living beings. To test this theory, the bacterial interaction of PA@AuNPs was studied using Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa cultures, as well as the inhibition of the bovine serum albumin (BSA) protein. The real-time polymerase chain reaction (RT-PCR) is used to measure the expression of target genes. PA@AuNPs caused dose-dependent cell death in MDA-MB-231, a triple-negative breast cancer (BC) cell line, with an LC50 of -42.23 μL mL-1. It also caused apoptosis in BC cells. The results indicated that in the early weeks, inflammatory cells (mostly neutrophils and macrophages) penetrated the connective tissue, but in the latter weeks, a substantial number of fibroblasts and fibrocytes were identified. Changes in vascular channels, extravasated red blood cells (RBCs), and necrosis are all indicators of growing tissue pathology. These data could point to a dynamic process including an anti-inflammatory response followed by tissue remodeling or repair. These findings show that PA@AuNPs were not hazardous to the tested Sprague Dawley rats, are highly biocompatible, and can be used in a variety of biological applications.

Studying the synthesis, antimicrobial activity, and phenol red removal of gelatin-stabilized copper nanoparticles

This study presents a synthesis method for environmentally friendly copper nanoparticles using ascorbic acid and gelatin as key components. The influence of precursor concentration, reductant amount, and stabilizer on the process was systematically investigated to obtain optimal results for the synthesis. The optimal parameters for forming copper nanoparticles, including 20 g per L gelatin, 19.3 mM (AcO)2Cu, and 41.5 mM ascorbic acid, were determined using a central composite design of the response surface methodology. Successful generation of pure copper nanoparticles with both spherical and cylindrical shapes, whose sizes were 43.1 and 105.2 nm, respectively, was confirmed by X-ray diffraction analysis and transmission electron microscopy. The synthesized nanomaterial was stable for a two-week storage time after which they gradually oxidized into Cu2+ ions. During antimicrobial activity testing, the synthesized nanoparticles displayed distinctive ability to inhibit the growth of Gram-positive bacteria (Lactobacillus fermentum, Bacillus subtilis, and Staphylococcus aureus), Gram-negative bacteria (Escherichia coli), and cancer cells (A549, Hep-G2, KB, and MCF7). Copper nanoparticles synthesized by chemical reduction demonstrated notable inhibitory activity against various pathogenic fungi that affect plants, including Fusarium solani, Rhizoctonia solani, and Colletotrichum gloeosporioides. Additionally, the catalytic activity of the produced nanomaterial with a bandgap energy of 2.14 eV and a specific surface area of 40.6 m2 g-1 was explored in the degradation of phenol, a common dye used in laboratories and industries. An optimized phenol red removal of 94.4% was achieved after a 540 second reaction time using response surface methodology, specifically a central composite design with an optimal dosage of copper nanoparticles at 31.5 ppm, a NaBH4 concentration of 53.1 mM, and a pH of 7.5.

Gold nanoparticles "AuNPs" -mediated amelioration of experimentally toxic-induced cerebellar syndrome: Insights into cytomolecular and immuno-histochemical modifications, with a focus on CREB/ Tau modulation

Toxic-induced cerebellar syndrome (TOICS) poses substantial neurological challenges, given its diverse causes and complex manifestations. Gold nanoparticles (AuNPs) have gained significant attention owing to enhanced biocompatibility for therapeutic interventions. We aimed to investigate the impacts of AuNPs on cerebellar cytomolecular, immunohistochemical and ultrastructural alterations in the context of phenytoin-experimentally induced TOICS. Thirty male albino rats were assigned randomly to three equal groups; control, phenytoin (PHT) and PHT+ AuNPs groups. Cerebellar sections were examined histopathologically, ultra-structurally and immunohistochemically for GFAP and p-Tau. Cerebellar tissues were evaluated for TNF-α, IL-1β, MDA, CAT, SOD and CREB mRNA. Our data confirmed observable amelioration of histopathological and ultrastructural cerebellar alterations of Purkinje and granule cells after AuNPs cotreatment. Histomorphometric measures revealed AuNPs-induced significant downregulation of p-Tau and GFAP immune-expression. Concurrently, TNF-α, IL-1β, MDA were significantly quenched in cerebellar tissues after AuNPs cotreatment, on contrary to notable restoration of CAT, SOD and CREB mRNA levels. These outcomes confirm that AuNPs hold promise as a therapeutic strategy for TOICS, warranting further exploration of their mechanisms and clinical applications in cerebellar disorders.

Polydopamine-assisted decoration of silver nanoparticles on gold nanorods for photothermal and chemical antimicrobial applications

AuNRs@PDA@AgNPs were prepared by assembling AgNPs on AuNRs with the assistance of PDA, realizing synergistic photothermal and chemical sterilization.

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.

The Synergistic Potential of Hydrogel Microneedles and Nanomaterials: Breaking Barriers in Transdermal Therapy

The stratum corneum, which acts as a strong barrier against external agents, presents a significant challenge to transdermal drug delivery. In this regard, microneedle (MN) patches, designed as modern systems for drug delivery via permeation through the skin with the ability to pass through the stratum corneum, are known to be convenient, painless, and effective. In fact, MN have shown significant breakthroughs in transdermal drug delivery, and among the various types, hydrogel MN (HMNs) have demonstrated desirable inherent properties. Despite advancements, issues such as limited loading capacity, uncontrolled drug release rates, and non-uniform therapeutic approaches persist. Conversely, nanomaterials (NMs) have shown significant promise in medical applications, however, their efficacy and applicability are constrained by challenges including poor stability, low bioavailability, limited payload capacity, and rapid clearance by the immune system. Incorporation of NMs within HMNs offers new prospects to address the challenges associated with HMNs and NMs. This combination can provide a promising field of research for improved and effective delivery of therapeutic agents and mitigate certain adverse effects, addressing current clinical concerns. The current review highlights the use of NMs in HMNs for various therapeutic and diagnostic applications.

Recent Advances in Nanomaterial-Based Biosignal Sensors

Recent research for medical fields, robotics, and wearable electronics aims to utilize biosignal sensors to gather bio-originated information and generate new values such as evaluating user well-being, predicting behavioral patterns, and supporting disease diagnosis and prevention. Notably, most biosignal sensors are designed for body placement to directly acquire signals, and the incorporation of nanomaterials such as metal-based nanoparticles or nanowires, carbon-based or polymer-based nanomaterials-offering stretchability, high surface-to-volume ratio, and tunability for various properties-enhances their adaptability for such applications. This review categorizes nanomaterial-based biosignal sensors into three types and analyzes them: 1) biophysical sensors that detect deformation such as folding, stretching, and even pulse, 2) bioelectric sensors that capture electric signal originating from human body such as heart and nerves, and 3) biochemical sensors that catch signals from bio-originated fluids such as sweat, saliva and blood. Then, limitations and improvements to nanomaterial-based biosignal sensors is depicted. Lastly, it is highlighted on deep learning-based signal processing and human-machine interface applications, which can enhance the potential of biosignal sensors. Through this paper, it is aim to provide an understanding of nanomaterial-based biosignal sensors, outline the current state of the technology, discuss the challenges that be addressed, and suggest directions for development.

Biomedical applications of peptide-gold nanoarchitectonics

Gold nanoparticles (AuNPs) have become a focus of interest in biomedicine due to their unique properties. By attaching peptides to these nanoparticles (NPs), they can be utilized for a wide range of applications. Peptides, which are short chains of amino acids, can be customized for specific molecular interactions, making them ideal for delivering AuNPs to particular cells or tissues. One of the peptide-AuNP-based bio-nano technological approaches involves targeted drug delivery. Including peptides as targeting agents, these NPs can be designed to bind to specific cell receptors or biomarkers. This allows for the direct delivery of therapeutic agents to diseased cells while minimizing unwanted side effects, improving the effectiveness of treatments. Additionally, peptide-functionalized AuNPs (PAuNPs) are crucial for imaging and diagnostics. By functionalizing the NPs with peptides that bind to specific molecular targets, such as cancer biomarkers, these NPs can be used to visualize diseased tissues. This enables the early detection of diseases and helps in determining the severity of conditions for better diagnosis and treatment outcomes. Moreover, PAuNPs have displayed promising potential in photothermal therapy. Once PAuNPs uptake and penetrate target cancer cells effectively, these NPs generate heat when exposed to specific wavelengths of light, efficiently eliminating tumors while preserving healthy surrounding tissues. Therefore, in this paper, we systematically review the potential of PAuNPs in various biomedical applications, including therapy and diagnosis, providing a future perspective.

A simple and highly sensitive colorimetric assay for the visual detection of lead and chromium using ascorbic acid capped gold nanoparticles

Lead (Pb2+) and hexavalent chromium (Cr6+) are highly toxic pollutants with no safe exposure levels, posing significant health risks globally, especially in developing countries. Current detection methods for these metals are often complex and inaccessible, highlighting the urgent need for innovative approaches. In this study, we present a rapid, cost-effective colorimetric assay utilizing ascorbic acid-capped gold nanoparticles (AuNPs) for the selective detection of Pb2+ and Cr3+/6+ ions at levels recommended by regulatory bodies such as the WHO and EPA. The synthesis of our AuNPs was achieved by reducing gold(III) chloride with ascorbic acid, resulting in stable, negatively charged nanoparticles, as characterized by dynamic light scattering, UV-vis spectroscopy and high-resolution transmission electron microscopy. Our method demonstrated high sensitivity, with limits of detection (LOD) of 5.4 ± 0.25 ppb for Pb2+, and 6.3 ± 0.23 ppb for Cr6+, confirming specificity towards these ions in various water samples. The assay's efficacy was validated in real-world applications, including testing drinking water from multiple sources and assessing the performance of filtration systems. This straightforward assay offers a promising tool for monitoring water quality, enhancing public health initiatives and accessibility to critical environmental testing.

Shark chondroitin sulfate gold nanoparticles: A biocompatible apoptotic agent for osteosarcoma

Osteosarcoma is a highly aggressive tumor that originates in the bone and often infiltrates nearby bone cells. It is the most prevalent type of primary bone cancer among the various bone malignancies. Traditional cancer treatment methods such as surgery, chemotherapy, immunotherapy, and radiotherapy have had restricted success. However, the integration of nanotechnology into cancer research has led to notable progress. One promising area is the use of marine-derived polysaccharide-based nano formulations for treating various human diseases, including cancer. This study presents a straightforward method for synthesizing biocompatible gold nanoparticles (AuNPs), utilizing sodium borohydride as a reducing agent and a cost-effective, water-soluble chondroitin sulfate (CS) derived from shark cartilage as a stabilizing agent. The synthesized CS-Au NPs appeared purple and were mainly spherical, with 40.768 nm of average size. Cytotoxicity assays (MTT) indicated that CS-Au NPs significantly reduced the viability of human osteosarcoma cells (MG63) at 100 μg/mL, while it showed no cytotoxic effects on mouse embryonic fibroblast cells (NIH3T3) at the same concentration. The observed toxicity of the CS-Au NPs was linked to a rise in the production of reactive oxygen species (ROS) within damaged mitochondria. ROS generation and changes in mitochondrial membrane potential were detected in MG63 cells treated with CS-Au NPs. Furthermore, apoptotic analysis through ethidium bromide dual staining and flow cytometry demonstrated that CS-Au NPs at higher concentrations significantly increased the amount of apoptotic cells, as demonstrated by acridine orange/ethidium bromide staining. Flow cytometry also confirmed that CS-Au NPs activated the apoptotic pathway in MG63 cells.

Gold Nanoparticle Detection with Two-Photon Excitation Fluorescence Lifetime Imaging of NAD(P)H in Cancer Cells: An Analytical Approach to Separate Nanoparticle and NAD(P)H Signals

Gold nanoparticles (AuNPs) have shown promise for applications in the diagnosis and treatment of different diseases, including cancer. Understanding the effect of AuNPs on metabolic reprogramming in cancer cells at the single cell level is of high importance for improving the efficacy and safety. Fluorescence lifetime imaging microscopy (FLIM) of nicotinamide adenine dinucleotide (phosphate) hydrogen (NAD(P)H) as a main metabolic cofactor and an indicator of metabolic reprogramming in cancer cells enables real-time monitoring of cancer cell metabolism in response to different treatments, including AuNPs. However, NPs such as AuNPs can be a potential source of signals themselves, which provides opportunities to measure the NP internalization, but it is also important to minimize confounding effects on metabolic measurements. In this study, we detected inherent photoluminescence (PL) from the AuNPs in treated prostate cancer cells (PC-3 cell line) as well as in solution at the NAD(P)H emission wavelength. We developed an analysis approach to minimize the confounding effect of the AuNPs' PL on metabolic measurements. On the other hand, we assessed the reliability of the intracellular AuNPs' PL as an estimator of AuNP uptake. To assess if intracellular AuNPs' PL may be dependent on the exposed cell type, we performed NAD(P)H FLIM imaging of AuNP-exposed SKBR-3 breast cancer cells, where we observed a similar AuNP PL but at a much lower level compared to PC-3 cells. We proposed that this difference can be attributed to the different levels of AuNP uptake or varying intracellular microenvironments.

Golden Therapeutic Approach to Combat Viral Diseases Using Gold Nanomaterials

Gold nanoparticles (AuNPs), due to their unique properties and surface modification abilities, have become a promising carrier for a range of biomedical applications. AuNPs have intrinsic antiviral characteristics because of their capacity to enhance drug distribution by making antiviral medications more stable and soluble, which assures that higher quantities reach the intended site. Through surface changes, AuNPs can bind directly to viral particles or infected cells, increasing therapeutic efficiency and reducing side effects. AuNPs efficiently damage cell membranes and hinder viral reproduction within a host cell. Furthermore, because of their large surface area-to-volume ratio, which enables many functional groups to connect, improving interaction with virus particles and ceasing their multiplication. By altering dimensions and morphology or conjugating it with additional antiviral drugs, AuNPs can array their synergistic antiviral activity. Thus, the development of AuNP conjugated therapy presents a promising avenue to address the demand for novel anti-viral therapeutics against infections resistant to several drugs.

Revolutionizing healthcare: inorganic medicinal nanoarchitectonics for advanced theranostics

Over the last two decades, advancements in nanomaterials and nanoscience have paved the path for the emergence of nano-medical convergence science, significantly impacting healthcare. In our review, we highlight how these advancements are applied in various biomedical technologies such as drug delivery systems, bio-imaging for diagnostic and therapeutic purposes. Recently, novel inorganic nanohybrid drugs have been developed, combining multifunctional inorganic nanomaterials with therapeutic agents (known as inorganic medicinal nanoarchitectonics). These innovative drugs are actively utilized in cutting-edge medical treatments, including targeted anti-cancer therapy, photo and radiation therapy, and immunotherapy. This review provides a detailed overview of the current development status of inorganic medicinal nanoarchitectonics and explores potential future directions in their advancements.

Red-light Emitting Orthogonally Trireactive Gold Nanoclusters for the Synthesis of Multifunctionalized Nanomaterials

For the development of highly multifunctionalized nanomaterials, the introduction of functional molecules on gold nanoclusters containing thiols preinstalled with connecting groupsconstitutes a promising approach. However, the uniform introduction of multiple connecting groups while avoiding side reactions is a challenging task. Herein, the synthesis of gold nanoclusters (ca. 1 nm) coated with thiol peptides bearing azido, amino, and aminooxy groups is reported. These nanoclusters emit red-light before and after the functionalization, enabling application to cell imaging. A detailed structure analysis using transmission electron microscope and X-ray absorption spectroscopy reveals the formation of Aun(SR)m nanoclusters as promising motifs for red-light emission. The sequential modification of the trireactive nanoclusters with RGD (Arg-Gly-Asp) peptides, metal chelators, and anticancer drugs via [3+2] cycloaddition, oximation, and amidation reactions at each functional group furnish red-light-emissive nanomaterials exhibiting remarkable toxicity against A549 human lung cancer cells. Integration of the multiligation chemistry and gold nanocluster engineering pave the way toward the development of advanced multifunctional nanomaterials for biological applications.

Targeted gold nanoparticles for ovarian cancer (Review)

Among all malignant gynecological tumors, ovarian cancer (OC) has the highest mortality rate. OC is often diagnosed at advanced and incurable stages; however, early diagnosis can enable the use of optimized and personalized treatments. Intensive research into the synthesis and characterization of gold nanoparticles (AuNPs) has been performed with the aim of developing innovative materials for use in biological and photothermal therapies for OC. AuNPs can be chemically modified and functionalized by binding to a variety of organic compounds and biomolecules, such as peptides, antibodies and therapeutic agents, via simple synthetic processes. They are particularly suitable for use as carriers for drug delivery. In the present review, the synthesis and characteristics of AuNPs are summarized, and their potential in OC therapy are discussed.

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.

Dextran-Encapsulated Nanoparticles and Super-Nanoparticle Assemblies: Preparation from Quantum Dots, Fluorescent Polymers, and Magnetic Nanoparticles for Application to Cellular Immunolabeling

Nanoparticles (NPs) continue to be developed as labels for bioanalysis and imaging due to their small size and, in many cases, emergent properties such as photoluminescence (PL) and superparamagnetism. Some applications stand to benefit from amplification of the advantageous properties of a NP, but this amplification is not a simple matter of scaling for size-dependent properties. One promising approach to amplification is, therefore, to assemble many copies of a NP into a larger but still nanoscale and colloidal entity. Here, we use multiple types of hydrophobic nanocrystal to show that amphiphilic dextran is a versatile material for the preparation and surface functionalization of such super-NP assemblies: CdSe/CdS/ZnS quantum dots (QDs), InP/ZnS QDs, and Si QDs; iron oxide magnetic NPs (MNPs); composites of QDs and MNPs; and composites of QDs and MNPs with fluorene-based and phenylenevinylene-based conjugated polymers. The amphiphilic dextran was also useful for the preparation of conjugated polymer NPs (CPNs) without the inclusion of inorganic nanocrystals. The prepared super-NPs and CPNs were characterized, physically and photophysically, at both the ensemble and the single-particle levels. Per colloidal entity, the super-QDs were orders of magnitude brighter than the individual QDs. This enhancement enabled assemblies of nominally more benign InP/ZnS and Si QDs to be competitive alternative materials to CdSe/CdS/ZnS QDs, which are normally much brighter when compared as individual nanocrystals. The dextran functionalization imparted low nonspecific binding and enabled the use of tetrameric antibody complexes (TACs) for simple and selective immunolabeling of cells with all of the prepared super-NP, CPN, and composite materials. Labeling with the super-QDs provided significantly enhanced PL signals, the super-MNPs enabled magnetic pull-down of cells, and both capabilities were concurrently available with composite assemblies. Overall, this study demonstrates that the preparatory method and functional benefits of amphiphilic dextran extend to a range of hydrophobic materials and combinations thereof. There is strong potential for assembling a diverse set of property-amplified designer labels that are ready-made for in vitro applications in bioanalysis and imaging.

Single gold nanowires with ultrahigh (>104) aspect ratios by triphasic electrodeposition

Due to their superior optical and electrical properties, gold nanowires are used ubiquitously across industries. Current techniques for fabricating such structures are often expensive, involving multiple steps, cleanroom operation, and limited ability for a user to controllably place a nanowire at a desired location. Here, we introduce the concept of triphasic electrodeposition, where metal salts act as antagonistic salts at the liquid|liquid interface, leading to their increased concentration at this phase boundary. We show that the electrodeposition of ultra-high aspect ratio gold nanowires may be achieved in a one-step, one-pot method by submerging a conductor in contact with two phases: an organic phase containing HAuCl4 and a quaternary ammonium salt, and an aqueous phase containing potassium chloride. Changing electrodeposition parameters in the triphasic system allows tunability of important features of the nanowire, such as size and thickness. Furthermore, this new method provides an impressive ability to choose the geometry and precise positioning of deposited nanowires simply by changing where a liquid|liquid interface contacts the electrode surface.

The Application of Nanoparticle-Based Imaging and Phototherapy for Female Reproductive Organs Diseases

Various female reproductive disorders affect millions of women worldwide and bring many troubles to women's daily life. Let alone, gynecological cancer (such as ovarian cancer and cervical cancer) is a severe threat to most women's lives. Endometriosis, pelvic inflammatory disease, and other chronic diseases-induced pain have significantly harmed women's physical and mental health. Despite recent advances in the female reproductive field, the existing challenges are still enormous such as personalization of disease, difficulty in diagnosing early cancers, antibiotic resistance in infectious diseases, etc. To confront such challenges, nanoparticle-based imaging tools and phototherapies that offer minimally invasive detection and treatment of reproductive tract-associated pathologies are indispensable and innovative. Of late, several clinical trials have also been conducted using nanoparticles for the early detection of female reproductive tract infections and cancers, targeted drug delivery, and cellular therapeutics. However, these nanoparticle trials are still nascent due to the body's delicate and complex female reproductive system. The present review comprehensively focuses on emerging nanoparticle-based imaging and phototherapies applications, which hold enormous promise for improved early diagnosis and effective treatments of various female reproductive organ diseases.

Capped Plasmonic Gold and Silver Nanoparticles with Porphyrins for Potential Use as Anticancer Agents-A Review

Photothermal therapy (PTT) and photodynamic therapy (PDT) are potential cancer treatment methods that are minimally invasive with high specificity for malignant cells. Emerging research has concentrated on the application of metal nanoparticles encapsulated in porphyrin and their derivatives to improve the efficacy of these treatments. Gold and silver nanoparticles have distinct optical properties and biocompatibility, which makes them efficient materials for PDT and PTT. Conjugation of these nanoparticles with porphyrin derivatives increases their light absorption and singlet oxygen generation that create a synergistic effect that increases phototoxicity against cancer cells. Porphyrin encapsulation with gold or silver nanoparticles improves their solubility, stability, and targeted tumor delivery. This paper provides comprehensive review on the design, functionalization, and uses of plasmonic silver and gold nanoparticles in biomedicine and how they can be conjugated with porphyrins for synergistic therapeutic effects. Furthermore, it investigates this dual-modal therapy's potential advantages and disadvantages and offers perspectives for future prospects. The possibility of developing gold, silver, and porphyrin nanotechnology-enabled biomedicine for combination therapy is also examined.

Non-viral vectors combined delivery of siRNA and anti-cancer drugs to reverse tumor multidrug resistance

Multidrug resistance (MDR) of tumors is one of the main reasons for the failure of chemotherapy. Multidrug resistance refers to the cross-resistance of tumor cells to multiple antitumor drugs with different structures and mechanisms of action. Current strategies to reverse multidrug resistance in tumors include MDR inhibitors and RNAi technology. siRNA is a small molecule RNA that is widely used in RNAi technology and has the characteristics of being prepared in large quantities and chemically modified. However, siRNA is susceptible to degradation in vivo. The effect of siRNA therapy alone is not ideal, so siRNA and anticancer drugs are administered in combination to reverse the MDR of tumors. Non-viral vectors are now commonly used to deliver siRNA and anticancer drugs to tumor sites. This article will review the progress of siRNA and chemotherapeutic drug delivery systems and their mechanisms for reversing multidrug resistance.

Understanding Macrophage Interaction with Antimony-Doped Tin Oxide Plasmonic Nanoparticles

Antimony-doped tin oxide nanoparticles (ATO NPs) have emerged as a promising tool in biomedical applications, namely robust photothermal effects upon near-infrared (NIR) light exposure, enabling controlled thermal dynamics to induce spatial cell death. This study investigated the interplay between ATO NPs and macrophages, understanding cellular uptake and cytokine release. ATO NPs demonstrated biocompatibility with no impact on macrophage viability and cytokine secretion. These findings highlight the potential of ATO NPs for inducing targeted cell death in cancer treatments, leveraging their feasibility, unique NIR properties, and safe interactions with immune cells. ATO NPs offer a transformative platform with significant potential for future biomedical applications by combining photothermal capabilities and biocompatibility.

Gold Nanoparticles for Retinal Molecular Optical Imaging

The incorporation of gold nanoparticles (GNPs) into retinal imaging signifies a notable advancement in ophthalmology, offering improved accuracy in diagnosis and patient outcomes. This review explores the synthesis and unique properties of GNPs, highlighting their adjustable surface plasmon resonance, biocompatibility, and excellent optical absorption and scattering abilities. These features make GNPs advantageous contrast agents, enhancing the precision and quality of various imaging modalities, including photoacoustic imaging, optical coherence tomography, and fluorescence imaging. This paper analyzes the unique properties and corresponding mechanisms based on the morphological features of GNPs, highlighting the potential of GNPs in retinal disease diagnosis and management. Given the limitations currently encountered in clinical applications of GNPs, the approaches and strategies to overcome these limitations are also discussed. These findings suggest that the properties and efficacy of GNPs have innovative applications in retinal disease imaging.

Nanotechnology Advances in the Detection and Treatment of Lymphoid Malignancies

Lymphoid malignancies are complex diseases with distinct biological behaviors, clinical presentations, and treatment responses. Ongoing research and advancements in biotechnology enhance the understanding and management of these malignancies, moving towards more personalized approaches for diagnosis and treatment. Nanotechnology has emerged as a promising tool to improve some limitations of conventional diagnostics as well as treatment strategies for lymphoid malignancies. Nanoparticles (NPs) offer unique advantages such as enhanced multimodal detection, drug delivery, and targeted therapy capabilities, with the potential to improve precision medicine and patient outcomes. Here, we comprehensively examine the current landscape of nanoconstructs applied in the management of lymphoid disease. Through a comprehensive analysis of preclinical studies, we highlight the translational potential of NPs in revolutionizing the field of hematological malignancies, with a specific focus on lymphoid neoplasms.

Chitosan-stabilized gold nanoparticles decorated with a thiodiacetic acid nanoprobe for selective detection of arsenic(iii) in rice and water samples

A sensitive and selective method for the detection of arsenic(iii) (As3+) based on chitosan-stabilized gold nanoparticles (CS/AuNPs) decorated with a 2,2'-thiodiacetic acid (TDA) nanoprobe was developed and used to detect and indicate the contamination of rice, drinking water and environmental water samples. AuNPs were reduced and stabilized with CS and subsequently functionalized with TDA. As3+ interacted with the carboxylate group of TDA to form an As-TDA complex, inducing the aggregation of CS/AuNPs@TDA. The aggregation of CS/AuNPs@TDA was accompanied with a change in color from red to bluish purple and a shift in surface plasmon resonance wavelength from 525 nm to 645 nm. The response for the detection of As3+ was linear at concentrations from 10 to 1000 μg L-1 with a limit of detection of 6.1 μg L-1. The method exhibited selectivity toward As3+ among various cations (As5+, Cu2+, Fe3+, Fe2+, Hg2+, Al3+, Cr3+, Cd2+, Co2+, Ni2+, Pb2+ and Zn2+) and anions (Br-, Cl-, F-, SO4 2-, NO3 - and PO4 2-). The CS/AuNPs@TDA nanoprobe was applied to detect As3+ in rice, drinking water and environmental water samples. The results were consistent with those obtained via inductively coupled plasma-optical emission spectrometry (ICP-OES). Satisfactory recoveries ranging from 88.22% to 105.74% (RSDs of 0.25-2.99%) were obtained from spiked samples.

Detection of proteins with ascorbic acid-capped gold nanoparticles: a simple and highly sensitive colorimetric assay

We report a simple and highly sensitive colorimetric method for the detection and quantification of proteins, based on the aggregation of ascorbic acid (AA) capped gold nanoparticles (AuNPs) by proteins. The interactions between our AuNPs and nine different proteins of various sizes and shapes (cytochrome C (12 kDa), lysozyme (14.3 kDa), myoglobin (17 kDa), human serum albumin (66 kDa), bovine serum albumin (66.4 kDa), human transferrin (80 kDa), aldolase (160 kDa), catalase (240 kDa), and human H-ferritin (500 kDa)) generated similar AuNPs-protein absorption spectra in a concentration-dependent manner in the range of 1-15 nM. Upon the addition of a protein, the UV-visible spectra of AuNPs-protein conjugates shifted from 524 nm for the AuNps alone to longer wavelength (600-750 nm) due to the presence of one of these proteins. This bathochromic shift is accompanied by a color change from a cherry red, to dark purple, and then light grey or colorless if excess protein has been added, indicating the formation of AuNPs-protein conjugates followed by protein-induced aggregation of the AuNPs. High-resolution transmission electron microscopy images revealed uniformly distributed spherical nanoparticles with an average size of 27.5 ± 15.2 nm, increasing in size to 39.6 ± 12.9 nm upon the addition of a protein, indicating the formation of AuNPs-protein conjugates in solution. A general mechanism for the protein-induced aggregation of our AuNPs is proposed. The consistent behavior observed with the nine proteins tested in our study suggests that our assay can be universally applied for the quantification of pure proteins in a solution, regardless of size, shape, or molecular weight.

Novel approach for green synthesis of stable gold nanoparticles with dried turmeric root extract: investigations on sensor and catalytic applications

In this study, we present the synthesis of gold nanoparticles (AuNPs) using a completely green synthesis method without the use of any additional functionalizing agent, except dried turmeric root extract. The significant synthesis parameters were optimized, and the applicability of AuNPs was investigated in areas such as plasmonic and fluorescent sensing of aluminum (Al3⁺) and chromium (Cr3⁺) ions, reduction of 4-nitrophenol (4-NP), and degradation of methylene blue (MB) and methyl orange (MO) dyes. Characterization studies were performed using UV-Vis spectroscopy, TEM, FTIR, and XRD, revealing that the AuNPs predominantly had a spherical morphology and a very small particle size of 8.5 nm, with stability maintained up to 120 days. The developed AuNP-based plasmonic sensors relied on aggregation-induced decreases in absorption, along with a red shift in the spectra. Fluorescence sensing demonstrated a linear increase in intensity with increasing concentrations of Al3⁺ and Cr3⁺, with detection limits of 0.83 and 1.19 nM, respectively. The catalytic activities of AuNPs were tested in reducing 4-NP and degradations of MB and MO dyes (binary system) in tap water and wastewater, with the reactions following pseudo-first-order kinetics. This study highlights the potential of AuNPs synthesized from turmeric roots for various environmental and sensing applications.

Agglomeration compaction promotes corrosion of gold nanoparticles

Engineered nanoparticles are increasingly being used in various areas of human activity. However, the degradation mechanism of nanobodies in harsh environments is still a puzzle for theory and experiment. We report here the results of optical spectroscopy and nanoparticle tracking analysis, quantifying agglomeration and sizing of 50 nm citrate stabilized gold nanoparticles (GNPs) in HCl solutions containing H2O2. The mechanism of a consecutive corrosion reaction of GNPs is discussed within the framework of the near-field approach. We found that the disappearance of single nanoparticles from a suspension does not occur due to their dissolution per se, but is a consequence of the formation of aggregates. The neutralization of electrostatic shielding at high ionic strength allows gold nanoparticles to approach the subnanometer distance within the region of capping defects, at which the Casimir and van der Waals attractive forces dominate. It is suggested that electric field fluctuations in the confined space between highly conductive gold nanoparticles cause complexant-stimulated loss of metal from the core in the contact area. Going beyond the charge screening limitations by constraining the reaction space and reducing the double electrical layer thickness allows for chemical processes flow along otherwise not accessible reaction pathways.

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.

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.

Advanced nanoparticles in osteoarthritis treatment

Osteoarthritis (OA) is the most prevalent degenerative joint disorder, affecting hundreds of millions of people globally. Current clinical approaches are confined to providing only symptomatic relief. Research over the past two decades has established that OA is not merely a process of wear and tear of the articular cartilage but involves abnormal remodelling of all joint tissues. Although many new mechanisms of disease have been identified in the past several decades, the efficient and sustainable delivery of drugs targeting these mechanisms in joint tissues remains a major challenge. Nanoparticles recently emerged as favoured delivery vehicles in OA treatment, offering extended drug retention, enhanced drug targeting, and improved drug stability and solubility. In this review, we consider OA as a disease affecting the entire joint and initially explore the pathophysiology of OA across multiple joint tissues, including the articular cartilage, synovium, fat pad, bone, and meniscus. We then classify nanoparticles based on their composition and structure, such as lipids, polymers, inorganic materials, peptides/proteins, and extracellular vesicles. We summarise the recent advances in their use for treatment and diagnosis of OA. Finally, we discuss the current challenges and future directions in this field. In conclusion, nanoparticle-based nanosystems are promising carriers that advance OA treatment and diagnosis.

Leveraging Tunable Nanoparticle Surface Functionalization to Alter Cellular Migration

Gold nanoparticles (AuNPs) are a promising platform for biomedical applications including therapeutics, imaging, and drug delivery. While much of the literature surrounding the introduction of AuNPs into cellular systems focuses on uptake and cytotoxicity, less is understood about how AuNPs can indirectly affect cells via interactions with the extracellular environment. Previous work has shown that the monocytic cell line THP-1's ability to undergo chemotaxis in response to a gradient of monocyte chemoattractant protein 1 (MCP-1) was compromised by extracellular polysulfonated AuNPs, presumably by binding to MCP-1 with some preference over other proteins in the media. The hypothesis to be explored in this work is that the degree of sulfonation of the surface would therefore be correlated with the ability of AuNPs to interrupt chemotaxis. Highly sulfonated poly(styrenesulfonate)-coated AuNPs caused strong inhibition of THP-1 chemotaxis; by reducing the degree of sulfonation on the AuNP surface with copolymers [poly(styrenesulfonate-co-maleate) of different compositions], it was found that medium and low sulfonation levels caused weak to no inhibition, respectively. Small, rigid molecular sulfonate surfaces were relatively ineffective at chemotaxis inhibition. Unusually, free poly(styrenesulfonate) caused a dose-dependent reversal of THP-1 cell migration: at low concentrations, free poly(styrenesulfonate) significantly inhibited MCP-1-induced chemotaxis. However, at high concentrations, free poly(styrenesulfonate) acted as a chemorepellent, causing a reversal in the cell migration direction.

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.

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.

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.

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.