The Basic Properties of Gold Nanoparticles and their Applications in Tumor Diagnosis and Treatment

Nanoengineering of mono (Au, Ag) and bimetallic (Ag-Au) alloy nanoparticles for dye degradation and toxicity assessment

This research entails the synthesis and catalytic exploration of bimetallic nanoparticles combining silver (Ag) and gold (Au). The Au concentration was systematically varied (20%, 40%, 60%, and 80%), alongside the utilization of CTAB surfactant for nanoparticle stabilization. UV visible spectroscopic analysis confirmed the formation and stability of synthesized Au, Ag and bimetallic (Ag-Au) nanoparticles. FESEM further confirmed the formation of uniform sized Au and Ag nanoparticles. Integration of Au into Ag resulted in bimetallic (Ag-Au) alloy nanoparticles with smaller dimensions as compared to individual Au and Ag nanoparticles. EDX spectra and mapping verified the composition of each synthesized bimetallic nanoparticle variant. The catalytic potential of the synthesized nanoparticles was methodically explored using UV-visible spectroscopy. All the synthesized nanoparticles showcased excellent catalytic efficacy. The synergistic effect of the alloyed bimetallic nanoparticles was found promising. Assessment of dye toxicity pre- and post-degradation was conducted using the ECOSAR program, indicating a reduction in dye toxicity following degradation.

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.

Advanced nanomedicines for the treatment of age-related macular degeneration

The critical and unmet medical need for novel therapeutic advancements in the treatment of age-related macular degeneration (AMD) cannot be overstated, particularly given the aging global population and the increasing prevalence of this condition. Current AMD therapy involves intravitreal treatments that require monthly or bimonthly injections to maintain optimal efficacy. This underscores the necessity for improved approaches, prompting recent research into developing advanced drug delivery systems to prolong the intervals between treatments. Nanoparticle-based therapeutic approaches have enabled the controlled release of drugs, targeted delivery of therapeutic materials, and development of smart solutions for the harsh microenvironment of diseased tissues, offering a new perspective on ocular disease treatment. This review emphasizes the latest pre-clinical treatment options in ocular drug delivery to the retina and explores the advantages of nanoparticle-based therapeutic approaches, with a focus on AMD, the leading cause of irreversible blindness in the elderly.

Development and characterization of a portable electrochemical aptasensor for IsdA protein and Staphylococcus aureus detection

Staphylococcus aureus (S. aureus) is recognized as one of the most common causes of gastroenteritis worldwide. This pathogen is a major foodborne pathogen that can cause many different types of various infections, from minor skin infections to lethal blood infectious diseases. Iron-regulated surface determinant protein A (IsdA) is an important protein on the S. aureus surface. It is responsible for iron scavenging via interaction with hemoglobin, haptoglobin, and hemoglobin-haptoglobin complexes. This study develops a portable aptasensor for IsdA and S. aureus detection using aptamer-modified gold nanoparticles (AuNPs) integrated into screen-printed carbon electrodes (SPCEs). The electrode system was made of three parts, including a carbon counter electrode, an AuNPs/carbon working electrode, and a silver reference electrode. The aptamer by Au-S bonding was conjugated on the electrode surface to create the aptasensor platform. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were utilized to investigate the binding interactions between the aptasensor and the IsdA protein. CV studies showed a linear correlation between varying S. aureus concentrations within the range of 101 to 106 CFU/mL, resulting in a limit of detection (LOD) of 0.2 CFU/mL. The results demonstrated strong reproducibility, selectivity, and sensitivity of the aptasensor for enhanced detection of IsdA, along with about 93% performance stability after 30 days. The capability of the aptasensor to directly detect S. aureus via the IsdA surface protein binding was further investigated in a food matrix. Overall, the aptasensor device showed the potential for rapid detection of S. aureus, serving as a robust approach to developing real-time aptasensors to identify an extensive range of targets of foodborne pathogens and beyond.

Multi-channel prismatic localized surface plasmon resonance biosensor for real-time competitive assay multiple COVID-19 characteristic miRNAs

A multi-channel prismatic localized surface plasmon resonance (LSPR) biosensor was developed for quantitative and real-time detection of multiple COVID-19 characteristic miRNAs. The well-dispersed and dense gold nanoparticles (AuNPs) arrays for LSPR biosensing were fabricated through a nano-thickness diblock copolymer template (BCPT). Both theoretical and experimental analyses were conducted to investigate the effects of particle size, interparticle spacing, and surface coverage on LSPR sensing spectrum and intensity sensitivity of varied AuNPs sizes. A competitive assay strategy was proposed and used for non-amplification miRNA detection with a low limit detection of 3.41 nM, while a four-channel prismatic LSPR system enables parallel detection of multiple miRNAs. Furthermore, this sensing strategy can effectively and specifically identify target miRNA, distinguish mismatched miRNA and interfering miRNA, and exhibit low non-specific adsorption. This BCPT-based LSPR biosensor demonstrates the practicality and potential of a multi-channel, adaptable, and integrated prismatic sensor in medical testing and diagnostic applications.

Core-Tunable Dendritic Polymer: A Folate-Guided Theranostic Nanoplatform for Drug Delivery Applications

Clinical application of anticancer drugs is mostly limited due to their hydrophobic nature, which often results in lower bioavailability and lesser retention in systemic circulation. Despite extensive research on the development of targeted drug delivery systems for cancer treatment, delivery of hydrophobic therapeutic drugs to tumor cells remains a major challenge in the field. To address these concerns, we have precisely engineered a new hyperbranched polymer for the targeted delivery of hydrophobic drugs by using a malonic acid-based A2B monomer and 1,6-hexanediol. The choice of monomer systems in our design allows for the formation of higher molecular weight polymers with hydrophobic cavities for the efficient encapsulation of therapeutic drugs that exhibit poor water solubility. Using several experimental techniques such as NMR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform-infrared (FT-IR), and gel permeation chromatography (GPC), the synthesized polymer was characterized, which indicated its dendritic structure, thermal stability, and amorphous nature, making it suitable as a drug delivery system. Following characterizations, theranostic nanoplatforms were formulated using a one-pot solvent diffusion method to coencapsulate hydrophobic drugs, BQU57 and doxorubicin. To achieve targeted delivery of loaded therapeutic drugs in A549 cancer cells, the surface of the polymeric nanoparticle was conjugated with folic acid. The therapeutic efficacy of the delivery system was determined by various cell-based in vitro experiments, including cytotoxicity, cell internalizations, reactive oxygen species (ROS), apoptosis, migration, and comet assays. Overall, findings from this study indicate that the synthesized dendritic polymer is a promising carrier for hydrophobic anticancer drugs with higher biocompatibility, stability, and therapeutic efficacy for applications in cancer therapy.

Metal-based nanoparticle in cancer treatment: lessons learned and challenges

Cancer, being one of the deadliest diseases, poses significant challenges despite the existence of traditional treatment approaches. This has led to a growing demand for innovative pharmaceutical agents that specifically target cancer cells for effective treatment. In recent years, the use of metal nanoparticles (NPs) as a promising alternative to conventional therapies has gained prominence in cancer research. Metal NPs exhibit unique properties that hold tremendous potential for various applications in cancer treatment. Studies have demonstrated that certain metals possess inherent or acquired anticancer capabilities through their surfaces. These properties make metal NPs an attractive focus for therapeutic development. In this review, we will investigate the applicability of several distinct classes of metal NPs for tumor targeting in cancer treatment. These classes may include gold, silver, iron oxide, and other metals with unique properties that can be exploited for therapeutic purposes. Additionally, we will provide a comprehensive summary of the risk factors associated with the therapeutic application of metal NPs. Understanding and addressing these factors will be crucial for successful clinical translation and to mitigate any potential challenges or failures in the translation of metal NP-based therapies. By exploring the therapeutic potential of metal NPs and identifying the associated risk factors, this review aims to contribute to the advancement of cancer treatment strategies. The anticipated outcome of this review is to provide valuable insights and pave the way for the advancement of effective and targeted therapies utilizing metal NPs specifically for cancer patients.

Biogenic fabrication of a gold nanoparticle sensor for detection of Fe3+ ions using a smartphone and machine learning

In recent years, smartphones have been integrated into rapid colorimetric sensors for heavy metal ions, but challenges persist in accuracy and efficiency. Our study introduces a novel approach to utilize biogenic gold nanoparticle (AuNP) sensors in conjunction with designing a lightbox with a color reference and machine learning for detection of Fe3+ ions in water. AuNPs were synthesized using the aqueous extract of Eleutherine bulbosa leaf as reductants and stabilizing agents. Physicochemical analyses revealed diverse AuNP shapes and sizes with an average size of 19.8 nm, with a crystalline structure confirmed via SAED and XRD techniques. AuNPs exhibited high sensitivity and selectivity in detection of Fe3+ ions through UV-vis spectroscopy and smartphones, relying on nanoparticle aggregation. To enhance image quality, we developed a lightbox and implemented a reference color value for standardization, significantly improving performance of machine learning algorithms. Our method achieved approximately 6.7% higher evaluation metrics (R 2 = 0.8780) compared to non-normalized approaches (R 2 = 0.8207). This work presented a promising tool for quantitative Fe3+ ion analysis in water.

Study of Highly Efficient Au/Pt Nanoparticles for Rapid Screening of Clostridium difficile

This study synthesized core/shell gold-platinum nanoparticles and characterized their colorimetric properties; ultraviolet-visible spectroscopy revealed that the synthesized nanoparticles exhibited distinct colors from conventional gold nanoparticles. Furthermore, the nanoparticles were subjected to lateral flow assays using Protein A, and the results revealed that they outperformed conventional spherical gold nanoparticles in terms of color development. This improvement can be attributed to the distinct core/shell structures of our nanoparticles. Further evaluation revealed that these nanoparticles could facilitate the detection of Clostridium difficile Toxin B visually at an extremely low concentration (1 ng/mL) without the requirement for advanced instrumentation. This substantial improvement in sensitivity can be attributed to the meticulous design and nanoscale engineering of the structure of the nanoparticles.

Effect of Polymer and Cell Membrane Coatings on Theranostic Applications of Nanoparticles: A Review

The recent decade has witnessed a remarkable surge in the field of nanoparticles, from their synthesis, characterization, and functionalization to diverse applications. At the nanoscale, these particles exhibit distinct physicochemical properties compared to their bulk counterparts, enabling a multitude of applications spanning energy, catalysis, environmental remediation, biomedicine, and beyond. This review focuses on specific nanoparticle categories, including magnetic, gold, silver, and quantum dots (QDs), as well as hybrid variants, specifically tailored for biomedical applications. A comprehensive review and comparison of prevalent chemical, physical, and biological synthesis methods are presented. To enhance biocompatibility and colloidal stability, and facilitate surface modification and cargo/agent loading, nanoparticle surfaces are coated with different synthetic polymers and very recently, cell membrane coatings. The utilization of polymer- or cell membrane-coated nanoparticles opens a wide variety of biomedical applications such as magnetic resonance imaging (MRI), hyperthermia, photothermia, sample enrichment, bioassays, drug delivery, etc. With this review, the goal is to provide a comprehensive toolbox of insights into polymer or cell membrane-coated nanoparticles and their biomedical applications, while also addressing the challenges involved in translating such nanoparticles from laboratory benchtops to in vitro and in vivo applications. Furthermore, perspectives on future trends and developments in this rapidly evolving domain are provided.

Identification of acetaldehyde based on plasmonic patterns of a gold nanostructure conjugated with chromophore and H2O2: a new platform for the rapid and low-cost analysis of carcinogenic agents by colorimetric affordable test strip (CATS)

Acetaldehyde, a prevalent carbonyl compound in fermented foods, poses challenges in various applications due to its reactivity. This study addresses the need for efficient acetaldehyde detection methods across biotechnological, environmental, pharmaceutical, and food sectors. Herein, we present a novel colorimetric/UV spectrophotometric approach utilizing gold nanoparticles (AuNPs), particularly gold nano-flowers (AuNFs), for sensitive acetaldehyde identification. The method exhibits a notable sensitivity, detecting acetaldehyde at concentrations as low as 0.1 μM. The mechanism involves the interaction of acetaldehyde molecules with AuNFs, leading to a significant change in the absorbance spectrum, which serves as the basis for detection. Moreover, its applicability extends to human biofluids, notably urine samples. Integration with a cost-effective one-drop microfluidic colorimetric device (OD-μPCD) enables the development of an affordable test strip (CATS). This semi-analytical device, employing a multichannel OD-μPCD, facilitates real-time analysis of acetaldehyde in human samples. Our findings demonstrate the pioneering utilization of AuNPs for selective and sensitive acetaldehyde detection, promising advancements in environmental and occupational safety standards, and laying a foundation for enhanced detection and monitoring of related volatile organic compounds (VOCs).

A Step Forward for the Treatment of Localized Prostate Cancer Using Gold Nanoparticles Combined with Laser Irradiation

Prostate cancer (PCA) is the second most common cancer diagnosis in men and the fifth leading cause of death worldwide. The conventional treatments available are beneficial to only a few patients and, in those, some present adverse side effects that eventually affect the quality of life of most patients. Thus, there is an urgent need for effective, less invasive and targeted specific treatments for PCA. Photothermal therapy (PTT) is a minimally invasive therapy that provides a localized effect for tumour cell ablation by activating photothermal agents (PTA) that mediate the conversion of the light beam's energy into heat at the site. As tumours are unable to easily dissipate heat, they become more susceptible to temperature increases. In the PTT field, gold nanoparticles (AuNPs) have been attracting interest as PTA. The aim of this study was to formulate AuNPs capable of remaining retained in the tumour and subsequently generating heat at the tumour site. AuNPs were synthesized and characterized in terms of size, polydispersity index (PdI), zeta potential (ZP), morphology and the surface plasmon resonance (SPR). The safety of AuNPs and their efficacy were assessed using in vitro models. A preliminary in vivo safety assessment of AuNPs with a mean size lower than 200 nm was confirmed. The morphology was spherical-like and the SPR band showed good absorbance at the laser wavelength. Without laser, AuNPs proved to be safe both in vitro (>70% viability) and in vivo. In addition, with laser irradiation, they proved to be relatively effective in PCA cells. Overall, the formulation appears to be promising for use in PTT.

Sustainable technologies for the recycling and upcycling of precious metals from e-waste

E-waste is the fastest growing solid waste in the world. Each year, over 50 million tonnes of e-waste are produced, with its rate increasing by 3-5 % annually. Currently, only 17 % of e-waste is properly recycled, leaving the majority managed unsustainably, thereby causing detrimental environmental and economic effects. Cleaner e-waste management technologies are essential to address this urgent and rapidly expanding issue. Precious metals within e-waste significantly contribute to recycling revenues. In this paper, we review state-of-the-art technologies for sustainable recycling and upcycling of these metals from e-waste, including cleaner extractive metallurgy, solution purification technologies, and direct synthesis of green nanomaterials. We also discuss the potential impacts and constraints of these technologies and provide recommendations for improving and implementing both existing and prospective technologies.

Rational approach to design gold nanoparticles for photothermal therapy: the effect of gold salt on physicochemical, optical and biological properties

Among the unique characteristics associated to gold nanoparticles (AuNPs) in biomedicine, their ability to convert light energy into heat opens ventures for improved cancer therapeutic options, such as photothermal therapy (PTT). PTT relies on the local hyperthermia of tumor cells upon irradiation with light beams, and the association of AuNPs with radiation within the near infrared (NIR) range constitutes an advantageous strategy to potentially improve PTT efficacy. Herein, it was explored the effect of the gold salt on the AuNPs' physicochemical and optical properties. Mostly spherical-like negatively charged AuNPs with variable sizes and absorbance spectra were obtained. In addition, photothermal features were assessed using in vitro phantom models. The best formulation showed the ability to increase their temperature in aqueous solution up to 19 °C when irradiated with a NIR laser for 20 min. Moreover, scanning transmission electron microscopy confirmed the rearrangement of the gold atoms in a face-centered cubic structure, which further allowed to calculate the photothermal conversion efficiency upon combination of theoretical and experimental data. AuNPs also showed local retention after being locally administered in in vivo models. These last results obtained by computerized tomography allow to consider these AuNPs as promising elements for a PTT system. Moreover, AuNPs showed high potential for PTT by resulting in in vitro cancer cells' viability reductions superior to 70 % once combine with 5 min of NIR irradiation.

Anti-CD64 Antibody-Conjugated PLGA Nanoparticles Containing Methotrexate and Gold for Theranostics Application in Rheumatoid Arthritis

Rheumatoid arthritis, an autoimmune disorder, exerts a considerable effect on quality of life. The inflammatory mechanism involved in rheumatoid arthritis is not clearly known, and therefore the need to develop effective medicines as well as new methods for early detection is a challenge. In this study, we developed PLGA nanoparticles containing gold and methotrexate in core and anti-CD64 antibody conjugated to nanoparticle surface via coupling process. The nanoparticles were examined for their surface morphology using SEM and TEM. The mean particle size, zeta potential, and PDI values of nanoparticles were 413.6 ± 2.89 nm, -10.12 ± 2.12 mV, and 0.23 ± 0.04, respectively, indicating good stability and particle homogeneity. In vitro drug release revealed a controlled release pattern with 93.44 ± 1.60% up to 72 h of release in the presence of pH 5.8, indicating the influence of pH and NIR on drug release. In vivo results on adjuvant-induced arthritis on Wistar rats indicated that animals receiving antibody-conjugated nanoparticles showed improvement in clinical indices and arthritic score as compared to non-conjugated nanoparticles and free drugs. This innovative drug delivery system will be an excellent strategy to maximize therapeutic effectiveness by limiting dosage-related side effects.

Designed Nanomaterials-Assisted Proteomics and Metabolomics Analysis for In Vitro Diagnosis

In vitro diagnosis (IVD) is pivotal in modern medicine, enabling early disease detection and treatment optimization. Omics technologies, particularly proteomics and metabolomics, offer profound insights into IVD. Despite its significance, omics analyses for IVD face challenges, including low analyte concentrations and the complexity of biological environments. In addition, the direct omics analysis by mass spectrometry (MS) is often hampered by issues like large sample volume requirements and poor ionization efficiency. Through manipulating their size, surface charge, and functionalization, as well as the nanoparticle-fluid incubation conditions, nanomaterials have emerged as a promising solution to extract biomolecules and enhance the desorption/ionization efficiency in MS detection. This review delves into the last five years of nanomaterial applications in omics, focusing on their role in the enrichment, separation, and ionization analysis of proteins and metabolites for IVD. It aims to provide a comprehensive update on nanomaterial design and application in omics, highlighting their potential to revolutionize IVD.

An application of carbohydrate polymers-based surface-modified gold nanoparticles for improved target delivery to liver cancer therapy - A systemic review

Gold nanoparticles have been broadly investigated as cancer diagnostic and therapeutic agents. Gold nanoparticles are a favorable drug delivery vehicle with their unique subcellular size and good biocompatibility. Chitosan, agarose, fucoidan, porphyran, carrageenan, ulvan and alginate are all examples of biologically active macromolecules. Since they are biocompatible, biodegradable, and irritant-free, they find extensive application in biomedical and macromolecules. The versatility of these compounds is enhanced because they are amenable to modification by functional groups like sulfation, acetylation, and carboxylation. In an eco-friendly preparation process, the biocompatibility and targeting of GNPs can be improved by functionalizing them with polysaccharides. This article provides an update on using carbohydrate-based GNPs in liver cancer treatment, imaging, and drug administration. Selective surface modification of several carbohydrate types and further biological uses of GNPs are focused on.

Plasmonic and Photothermal Properties of Silica-Capped Gold Nanoparticle Aggregates

Owing to their biocompatibility, gold nanoparticles have many applications in healthcare, notably for targeted drug delivery and the photothermal therapy of tumors. The addition of a silica shell to the nanoparticles can help to minimize the aggregation of the nanoparticles upon exposure to harsh environments and protect any Raman reporters adsorbed onto the metal surface. Here, we report the effects of the addition of a silica shell on the photothermal properties of a series of gold nanostructures, including gold nanoparticle aggregates. The presence of a Raman reporter at the surface of the gold nanoparticles also allows the structures to be evaluated by surface-enhanced Raman scattering (SERS). In this work, we explore the relationship between the degree of aggregation and the position and the extinction of the near-infrared plasmon on the observed SERS intensity and in the increase in bulk temperature upon near-infrared excitation. By tailoring the concentration of the silane and the thickness of the silica shell, it is possible to improve the photothermal heating capabilities of the structures without sacrificing the SERS intensity or changing the optical properties of the gold nanoparticle aggregates.

Ultrasmall ATP-Coated Gold Nanoparticles Specifically Bind to Non-Hybridized Regions in DNA

Here we report the synthesis of ultrasmall (2 nm in diameter) ATP-coated gold nanoparticles, ATP-NPs. ATP-NPs can be enlarged in a predictable manner by the surface-catalyzed reduction of gold ions with ascorbate, yielding uniform gold nanoparticles ranging in size from 2 to 5 nm in diameter. Using atomic force microscopy (AFM), we demonstrate that ATP-NPs can efficiently and selectively bind to a short non-hybridized 5A/5A region (composed of a 5A-nucleotide on each strand of the double helix) inserted into a circular double-stranded plasmid, Puc19. Neither small (1.4 nm in diameter) commercially available nanoparticles nor 5 nm citrate-protected ones are capable of binding to the plasmid. The unique ability to specifically target DNA regions characterized by local structural alterations of the double helix can pave the way for applications of the particles in the detection of genomic DNA regions containing mismatches and mutations that are common for cancer cells.

Heat Transfer in Gold Interfaces Capped with Thiolated Polyethylene Glycol: A Molecular Dynamics Study

Reverse nonequilibrium molecular dynamics simulations were used to study heat transport in solvated gold interfaces which have been functionalized with a low-molecular weight thiolated polyethylene glycol (PEG). The gold interfaces studied included (111), (110), and (100) facets as well as spherical nanoparticles with radii of 10 and 20 Å. The embedded atom model (EAM) and the polarizable density-readjusted embedded atom model (DR-EAM) were implemented to determine the effect of metal polarizability on heat transport properties. We find that the interfacial thermal conductance values for thiolated PEG-capped interfaces are higher than those for pristine gold interfaces. Hydrogen bonding between the thiolated PEG and solvent differs between planar facets and the nanospheres, suggesting one mechanism for enhanced transfer of energy, while the covalent gold sulfur bond appears to create the largest barrier to thermal conduction. Through analysis of vibrational power spectra, we find an enhanced population at low-frequency heat-carrying modes for the nanospheres, which may also explain the higher mean interfacial thermal conductance (G) value.

Polychaeta-mediated synthesis of gold nanoparticles: A potential antibacterial agent against Acute Hepatopancreatic Necrosis Disease (AHPND)-causing bacteria, Vibrio parahaemolyticus

Gold nanoparticles (AuNPs) have emerged as a promising application in aquaculture. Their nano-sized dimensions, comparable to pathogens offer potential solutions for combating antibiotic resistance. In this study, AuNPs were synthesized by using polychaetes, Marphysa moribidii as the bio-reducing agent. Modifications were made to reduce agglomeration in green-synthesized AuNPs through ultrasonication. The antibacterial activities of AuNPs against V. parahaemolyticus were evaluated. The physicochemical characteristics of the green synthesized AuNPs were comprehensively investigated. The successful formation of AuNPs was confirmed by the appearance of a red ruby colour and the presence of surface Plasmon resonance (SPR) absorption peaks at 530 nm as observed from UV-vis spectroscopy. Scanning electron microscopy (SEM) revealed spherical-shaped AuNPs with some agglomerations. Transmission electron microscopy (TEM) showed particle size of AuNPs ranging from 10 nm to 60 nm, meanwhile dynamic light scattering (DLS) analysis indicated an average particle size of 24.36 nm. X-ray diffraction (XRD) analysis confirmed the high crystallinity of AuNPs, and no AuNPs were detected in the polychaetes extracts prior to synthesis. A brief ultrasonication significantly reduced the tendencies for AuNPs to coalesce. The green-synthesized AuNPs demonstrated a remarkable antibacterial efficacy against V. parahaemolyticus. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) tests revealed that a concentration of 0.3 g/ml of AuNPs effectively inhibited V. parahaemolyticus. These findings highlighted the potential of green-synthesized AuNPs as antibacterial agents for the prevention and management of AHPND in aquaculture.

Interactions between gold nanoparticles with different morphologies and human serum albumin

Introduction: Three different shapes of gold nanoparticles were synthesized in this experiment. At the same time, studies compared their effects with human serum albumin (HSA). Methods: Gold nanoparticles (AuNPs) with three different morphologies, such as, nanospheres (AuNSs), nanorods (AuNRs), and nanoflowers (AuNFs) were synthesized via a seeding method and their characteristic absorption peaks were detected using ultraviolet-visible (UV-vis) absorption spectroscopy, Telectron microscopy (TEM), Dynamic Light Scattering (DLS) and Zeta potential measurements, circular dichroism (CD), and Fourier transform infrared spectroscopy (FTIR) to study the interactions between them and HSA. By comparing the thermodynamic parameters and quenching mechanism of the three materials, similarities and differences were determined in their interactions with HSA. Results: The results showed that with an increase in the concentration of the AuNPs with the three different morphologies, the UV-vis absorption peak intensity of the mixed solution increased, but its fluorescence intensity was quenched. This indicates that the three types of AuNPs interact with HSA, and that the interactions between them represent a static quenching process, which is consistent with the conclusions derived from three-dimensional fluorescence experiments. Through variable-temperature fluorescence experiments, the binding constants, number of binding sites, and thermodynamic parameters of the interactions between the three types of AuNPs and HSA were determined. The Gibbs free energy changes were <0, indicating that the reactions of the three types of AuNPs with HSA are spontaneous, resulting in associated matter. Binding constant measurements indicated that the strongest binding took place between the AuNFs and HSA. In addition, the results of fluorescence, CD spectroscopy, and FTIR showed that three different shapes of AuNPs can induce conformational changes in HSA and reduce the α-helix content. Among them, AuNFs have the smallest ability to induce conformational changes. Discussion: According to studies, AuNFs interact more favorably with HSA. This can be used as a reference for the administration of drugs containing AuNPs.

Functionalized GD2 Electrochemical Immunosensor to Diagnose Minimum Residual Disease of Bone Marrow in Neuroblastoma Effectively

Neuroblastoma (NB) is known as the "king of childhood tumors" due to its highly metastatic, recurrence-prone, and difficult-to-treat characteristics. International Neuroblastoma Risk Grading Group (INRG) has recommended GD2, a disialoganglioside expressed on neuroectodermal tumor cells, as the target for detecting minimal residual disease in bone marrow metastases of high-risk neuroblastoma in children. Therefore, accurately identifying GD2-positive cells is crucial for diagnosing children with high-risk NB. Here, we designed a graphene/AuNP/GD2 Ab-functionalized electrochemical biosensor for GD2 detection. A three-electrode system was processed using a screen-printed technique with a working electrode of indium tin oxide, a counter electrode of carbon, and a reference electrode of silver/silver chloride. Graphene/AuNPs were modified on the indium tin oxide electrode using chronoamperometric scans, and then, the GD2 antibody was modified on the biosensor by electrostatic adsorption to achieve sensitive and specific detection of GD2-positive cells in bone marrow fluid. The results showed that a graphene/AuNP/GD2 Ab-functionalized electrochemical biosensor achieved GD2-positive cell detection in the range of 102 cells/mL~105 cells/mL by differential pulse voltammetry. Bone marrow fluid samples from 12 children with high-risk NB were retained for testing on our biosensor and showed 100% compliance with the clinical application of the gold-standard immunocytochemical staining technique for detecting GD2-positive cells qualitatively. The GD2-based electrochemical assay can accurately detect children with high-risk NB, providing a rapidly quantitative basis for clinical diagnosis and treatment.

Progress and Challenges in the Diagnosis and Treatment of Brain Cancer Using Nanotechnology

Primary brain cancer or brain cancer is the overgrowth of abnormal or malignant cells in the brain or its nearby tissues that form unwanted masses called brain tumors. People with malignant brain tumors suffer a lot, and the expected life span of the patients after diagnosis is often only around 14 months, even with the most vigorous therapies. The blood-brain barrier (BBB) is the main barrier in the body that restricts the entry of potential chemotherapeutic agents into the brain. The chances of treatment failure or low therapeutic effects are some significant drawbacks of conventional treatment methods. However, recent advancements in nanotechnology have generated hope in cancer treatment. Nanotechnology has shown a vital role starting from the early detection, diagnosis, and treatment of cancer. These tiny nanomaterials have great potential to deliver drugs across the BBB. Beyond just drug delivery, nanomaterials can be simulated to generate fluorescence to detect tumors. The current Review discusses in detail the challenges of brain cancer treatment and the application of nanotechnology to overcome those challenges. The success of chemotherapeutic treatment or the surgical removal of tumors requires proper imaging. Nanomaterials can provide imaging and therapeutic benefits for cancer. The application of nanomaterials in the diagnosis and treatment of brain cancer is discussed in detail by reviewing past studies.

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.

Investigation of the Optical Nonlinearity for Au Plasmonic Nanoparticles Based on Ion Implantation

The Au ion implantation process has emerged as an effective and simple method to be utilized for the fabrication of opto-electronic materials and devices due to numerous fascinating features of Au nanoparticles such as surface plasmon resonance (SPR), large third-order nonlinearity and a fast response time. In this paper, we describe the fabrication of a novel Au nanoparticle saturable absorber (Au NP-SA) by embedding the Au NPs into a SiO2 thin film using the ion implantation process, which shows excellent saturable absorption features due to the localized surface plasmon resonance (LSPR) effect of Au NPs. A stable and high-quality pulsed laser with a repetition rate of 33.3 kHz and a single pulse energy of 11.7 nJ was successfully constructed with the Au NP-SA. Both the stable operation characteristic of the obtained Q-switched pulsed laser and the high repeatability of the fabrication process of the Au NP-SA were demonstrated. In addition, the simple feasibility and maturity of the ion implantation process allow for the plasmonic nanoparticles to be easily integrated into other types of opto-electronic materials and devices to further improve their performance, and shows immense potential for the production of wafer-level products.

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.

Nanoparticle-based delivery systems as emerging therapy in retinoblastoma: recent advances, challenges and prospects

Retinoblastoma is the most common intraocular malignancy in children. The treatment of this rare disease is still challenging in developing countries due to delayed diagnosis. The current therapies comprise mainly surgery, radiotherapy and chemotherapy. The adverse effects of radiation and chemotherapeutic drugs have been reported to contribute to the high mortality rate and affect patients' quality of life. The systemic side effects resulting from the distribution of chemotherapeutic drugs to non-cancerous cells are enormous and have been recognized as one of the reasons why most potent anticancer compounds fail in clinical trials. Nanoparticulate delivery systems have the potential to revolutionize cancer treatment by offering targeted delivery, enhanced penetration and retention effects, increased bioavailability, and an improved toxicity profile. Notwithstanding the plethora of evidence on the beneficial effects of nanoparticles in retinoblastoma, the clinical translation of this carrier is yet to be given the needed attention. This paper reviews the current and emerging treatment options for retinoblastoma, with emphasis on recent investigations on the use of various classes of nanoparticles in diagnosing and treating retinoblastoma. It also presents the use of ligand-conjugated and smart nanoparticles in the active targeting of anticancer and imaging agents to the tumour cells. In addition, this review discusses the prospects and challenges in translating this nanocarrier into clinical use for retinoblastoma therapy. This review may provide new insight for formulation scientists to explore in order to facilitate the development of more effective and safer medicines for children suffering from retinoblastoma.

Evolution of nanomedicine formulations for targeted delivery and controlled release

Nanotechnology research over the past several decades has been aimed primarily at improving the physicochemical properties of small molecules to produce druggable candidates as well as for tumor targeting of cytotoxic molecules. The recent focus on genomic medicine and the success of lipid nanoparticles for mRNA vaccines have provided additional impetus for the development of nanoparticle drug carriers for nucleic acid delivery, including siRNA, mRNA, DNA, and oligonucleotides, to create therapeutics that can modulate protein deregulation. Bioassays and characterizations, including trafficking assays, stability, and endosomal escape, are key to understanding the properties of these novel nanomedicine formats. We review historical nanomedicine platforms, characterization methodologies, challenges to their clinical translation, and key quality attributes for commercial translation with a view to their developability into a genomic medicine. New nanoparticle systems for immune targeting, as well as in vivo gene editing and in situ CAR therapy, are also highlighted as emerging areas.

Investigation of in vitro antimicrobial, antioxidant and antiproliferative activities of Nostoc calcicola biosynthesized gold nanoparticles

The cyanobacteria are the promising candidate for synthesizing gold nanoparticles (AuNPs), due to their ability to accumulate heavy metals from the cellular environment and additionally contain varied bioactive compounds as reducing and stabilizing agents. This study describes the N2-fixing cyanobacterium Nostoc calcicola-mediated bioreduction of AuNPs and the inherent antimicrobial, antioxidant, and antiproliferative activities in vitro. Biosynthesized Nc-AuNPs were characterized by spectral characterization techniques. The formation of AuNPs was physically confirmed by the colour change from pale green to dark violet. The UV-Vis analysis, further, proved the reduction in Nc-AuNPs with the cyanobacterium and showed a spectral peak at 527 nm. FESEM-EDX images suggested the surface morphology of the NPs as spherical, cuboidal, and size between 20 and 140 nm. The antimicrobial studies of Nc-AuNPs were carried out by agar-well diffusion method and MIC values against five pathogenic bacterial and two fungal strains were noted. The AuNPs exhibited potential antimicrobial activity against h-pathogenic bacteria with inhibitory zones ranging at 11-18 mm; against fungi ranging at 13-17 mm. Significant antioxidant potentialities were explored by a DPPH assay with an IC50 value of 55.97 μg/ mL. Furthermore, in the anticancer efficacy assay, the Nc-AuNPs inhibited cellular proliferation in human breast adenocarcinoma and cervical cancer cell lines at IC50 concentration, 37.3 μg/ml, and 44.5 μg/ml, respectively. Conclusively, N. calcicola would be an excellent source for synthesizing stable colloidal AuNPs that had significant credibility as phycological (algal) nanomedicines as novel prodrugs with multiple bioactivities.

Nanoplatforms: The future of oral cancer treatment

Background and Aims

Cytotoxicity is a key disadvantage of using chemotherapeutic drugs to treat cancer. This can be overcome by encapsulating chemotherapeutic drugs in suitable carriers for targeted delivery, allowing them to be released only at the cancerous sites. Herein, we aim to review the recent scientific developments in the utilization of nanotechnology-based drug delivery systems for treating oral malignancies that can lead to further improvements in clinical practice.

Methods

A comprehensive literature search was conducted on PubMed, Google Scholar, ScienceDirect, and other notable databases to identify recent peer-reviewed clinical trials, reviews, and research articles related to nanoplatforms and their applications in oral cancer treatment.

Results

Nanoplatforms offer a revolutionary strategy to overcome the challenges associated with conventional oral cancer treatments, such as poor drug solubility, non-specific targeting, and systemic toxicity. These nanoscale drug delivery systems encompass various formulations, including liposomes, polymeric nanoparticles, dendrimers, and hydrogels, which facilitate controlled release and targeted delivery of therapeutic agents to oral cancer sites. By exploiting the enhanced permeability and retention effect, Nanoplatforms accumulate preferentially in the tumor microenvironment, increasing drug concentration and minimizing damage to healthy tissues. Additionally, nanoplatforms can be engineered to carry multiple drugs or a combination of drugs and diagnostic agents, enabling personalized and precise treatment approaches.

Conclusion

The utilization of nanoplatforms in oral cancer treatment holds significant promise in revolutionizing therapeutic strategies. Despite the promising results in preclinical studies, further research is required to evaluate the safety, efficacy, and long-term effects of nanoformulations in clinical settings. If successfully translated into clinical practice, nanoplatform-based therapies have the potential to improve patient outcomes, reduce side effects, and pave the way for more personalized and effective oral cancer treatments.

Functionalized Metal Nanoparticles in Cancer Therapy

Currently, there are many studies on the application of nanotechnology in therapy. Metallic nanoparticles are promising nanomaterials in cancer therapy; however, functionalization of these nanoparticles with biomolecules has become relevant as their effect on cancer cells is considerably increased by photothermal and photodynamic therapies, drug nanocarriers, and specificity by antibodies, resulting in new therapies that are more specific against different types of cancer. This review describes studies on the effect of functionalized palladium, gold, silver and platinum nanoparticles in the treatment of cancer, these nanoparticles themselves show an anticancer effect. This effect is further enhanced when the NPs are functionalized with either antibodies, DNA, RNA, peptides, proteins, or folic acid and other molecules. These NPs can penetrate the cell and accumulate in the tumor tissue, resulting in a cytotoxic effect through the generation of ROS, the induction of apoptosis, cell cycle arrest, DNA fragmentation, and a photothermal effect. NP-based therapy is a new strategy that can be used synergistically with chemotherapy and radiotherapy to achieve more effective therapies and reduce side effects.

Eucalyptus globulus Mediated Green Synthesis of Environmentally Benign Metal Based Nanostructures: A Review

The progress in nanotechnology has effectively tackled and overcome numerous global issues, including climate change, environmental contamination, and various lethal diseases. The nanostructures being a vital part of nanotechnology have been synthesized employing different physicochemical methods. However, these methods are expensive, polluting, eco-unfriendly, and produce toxic byproducts. Green chemistry having exceptional attributes, such as cost-effectiveness, non-toxicity, higher stability, environment friendliness, ability to control size and shape, and superior performance, has emerged as a promising alternative to address the drawbacks of conventional approaches. Plant extracts are recognized as the best option for the biosynthesis of nanoparticles due to adherence to the environmentally benign route and sustainability agenda 2030 of the United Nations. In recent decades, phytosynthesized nanoparticles have gained much attention for different scientific applications. Eucalyptus globulus (blue gum) is an evergreen plant belonging to the family Myrtaceae, which is the targeted point of this review article. Herein, we mainly focus on the fabrication of nanoparticles, such as zinc oxide, copper oxide, iron oxide, lanthanum oxide, titanium dioxide, magnesium oxide, lead oxide, nickel oxide, gold, silver, and zirconium oxide, by utilizing Eucalyptus globulus extract and its essential oils. This review article aims to provide an overview of the synthesis, characterization results, and biomedical applications of nanoparticles synthesized using Eucalyptus globulus. The present study will be a better contribution to the readers and the students of environmental research.

Gold Nanoparticles: Construction for Drug Delivery and Application in Cancer Immunotherapy

Cancer immunotherapy is an innovative treatment strategy to enhance the ability of the immune system to recognize and eliminate cancer cells. However, dose limitations, low response rates, and adverse immune events pose significant challenges. To address these limitations, gold nanoparticles (AuNPs) have been explored as immunotherapeutic drug carriers owing to their stability, surface versatility, and excellent optical properties. This review provides an overview of the advanced synthesis routes for AuNPs and their utilization as drug carriers to improve precision therapies. The review also emphasises various aspects of AuNP-based immunotherapy, including drug loading, targeting strategies, and drug release mechanisms. The application of AuNPs combined with cancer immunotherapy and their therapeutic efficacy are briefly discussed. Overall, we aimed to provide a recent understanding of the advances, challenges, and prospects of AuNPs for anticancer applications.

Emerging trends in wearable glove-based sensors: A review

Glove-based wearable chemical sensors are universal analytical tools that provide surface analysis for various samples in dry or liquid form by swiping glove sensors on the sample surface. They are useful in crime scene investigation, airport security, and disease control for detecting illicit drugs, hazardous chemicals, flammables, and pathogens on various surfaces, such as foods and furniture. It overcomes the inability of most portable sensors to monitor solid samples. It outperforms most wearable sensors (e.g., contact lenses and mouthguard sensors) for healthcare monitoring by providing comfort that does not interfere with daily activities and reducing the risk of infection or other adverse health effects caused by prolonged usage. Detailed information is provided regarding the challenges and selection criteria for the desired glove materials and conducting nanomaterials for developing glove-based wearable sensors. Focusing on nanomaterials, various transducer modification techniques for various real-world applications are discussed. The steps taken by each study platform to address the existing issues are revealed, as are their benefits and drawbacks. The Sustainable Development Goals (SDGs) and strategies for properly disposing of used glove-based wearable sensors are critically evaluated. A glance at all the provided tables provides insight into the features of each glove-based wearable sensor and enables a quick comparison of their functionalities.

Evaluation of Machine Learning Interatomic Potentials for Gold Nanoparticles-Transferability towards Bulk

We analyse the efficacy of machine learning (ML) interatomic potentials (IP) in modelling gold (Au) nanoparticles. We have explored the transferability of these ML models to larger systems and established simulation times and size thresholds necessary for accurate interatomic potentials. To achieve this, we compared the energies and geometries of large Au nanoclusters using VASP and LAMMPS and gained better understanding of the number of VASP simulation timesteps required to generate ML-IPs that can reproduce the structural properties. We also investigated the minimum atomic size of the training set necessary to construct ML-IPs that accurately replicate the structural properties of large Au nanoclusters, using the LAMMPS-specific heat of the Au147 icosahedral as reference. Our findings suggest that minor adjustments to a potential developed for one system can render it suitable for other systems. These results provide further insight into the development of accurate interatomic potentials for modelling Au nanoparticles through machine learning techniques.

Ultrasensitive colorimetric detection of tetracyclines based on in-situ growth of gold nanoflowers

A colorimetric method based on in-situ generation of gold nanoflowers for the detection of tetracyclines (TCs) was proposed. We found that gold nanoflowers could be formed in the HAuCl₄-NH₂OH redox reaction directly without the addition of small-sized gold nanoparticles (Au NPs) as seeds when an alkaline borax buffer solution was employed as the reaction medium. Interestingly, the shape and size of the generated gold nanoflowers were regulated with TC. Briefly, large flower-like gold nanoparticles were formed with a low concentration of TC while small spherical gold nanoparticles were generated with a high concentration of TC. The generated gold nanoflowers exhibited different surface plasmon absorption (SPR) properties. Thus, a simple and rapid colorimetric method was established for the detection of TC antibiotics. This method exhibited high sensitivity for the detection of TC, oxytetracycline (OTC), and doxycycline (DC) with detection limits of 2.23 nM, 1.19 nM, and 5.81 nM, respectively. The proposed colorimetric method was applied to the determination of TC in both milk samples and water samples.

An Insight Into the Physicochemical Properties of Gold Nanoparticles in Relation to Their Clinical and Diagnostic Applications

The ease of formulation and surface modification of gold nanoparticles (AuNPs) by ligands, greater biocompatibility, non-cytotoxicity, and excellent optical properties are the characteristics that necessitate their application in clinical and genomic research. Not only that, but the extensive synthetic chemistry of AuNPs also offers precise control over physicochemical and optical properties owing to the inert, biocompatible, and non-toxic nature of the inner gold core. Another important property of AuNPs involves their incorporation into larger structures, including liposomes or polymeric materials, thereby increasing their capability of drug delivery in concurrent therapy and imaging labels for enhanced diagnostic applications. AuNPs are endowed with physical properties that suggest their use as adjuvants for radiotherapy and bio-imaging and in computed tomography (CT) scans, diagnostic systems, and therapy. Thus, these features strongly endorse the AuNPs in thrust areas of biomedical fields. The diverse properties of gold nanoparticles (AuNPs) have made them promising candidates in biomedical fields, including in the development of theranostics, which encompasses using these gold nanoparticles for both diagnosis and therapy simultaneously. To appreciate these and related applications, a need arises to review the basic principles and multifunctional attributes of AuNPs in relation to their advances in imaging, therapy, and diagnostics.

Metal-based nanomaterials and nanocomposites as promising frontier in cancer chemotherapy

Cancer is a disease associated with complex pathology and one of the most prevalent and leading reasons for mortality in the world. Current chemotherapy has challenges with cytotoxicity, selectivity, multidrug resistance, and the formation of stemlike cells. Nanomaterials (NMs) have unique properties that make them useful for various diagnostic and therapeutic purposes in cancer research. NMs can be engineered to target cancer cells for early detection and can deliver drugs directly to cancer cells, reducing side effects and improving treatment efficacy. Several of NMs can also be used for photothermal therapy to destroy cancer cells or enhance immune response to cancer by delivering immune-stimulating molecules to immune cells or modulating the tumor microenvironment. NMs are being modified to overcome issues, such as toxicity, lack of selectivity, increase drug capacity, and bioavailability, for a wide spectrum of cancer therapies. To improve targeted drug delivery using nano-carriers, noteworthy research is required. Several metal-based NMs have been studied with the expectation of finding a cure for cancer treatment. In this review, the current development and the potential of plant and metal-based NMs with their effects on size and shape have been discussed along with their more effective usage in cancer diagnosis and treatment.

Insights into Gold Nanoparticles Possibilities for Diagnosis and Treatment of the Head and Neck Upper Aerodigestive Tract Cancers

Background: Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer affecting people and accounts for more than 300,000 deaths worldwide. Improvements in treatment modalities, including immunotherapy, have demonstrated promising prognoses for eligible patients. Nevertheless, the five-year overall survival rate has not increased significantly, and the tumor recurrence ratio remains at 50% or higher, except for patients with HPV-positive HNSCC. Over the last decades, nanotechnology has provided promising tools, especially for biomedical applications, due to some remarkable physicochemical properties of numerous nanomaterials, particularly gold nanoparticles. This review addresses the features and some applications of gold nanoparticles reported in the literature over the last five years regarding the diagnosis and treatment of head and neck cancer, highlighting the exciting possibilities of this nanomaterial in oncology. Methods: The scientific papers selected for this review were obtained from the PubMed Advanced, Web of Science, Scopus, ClinicalTrials.gov, and Google Scholar platforms. Conclusions: Results from papers applying gold nanoparticles have suggested that their application is a feasible approach to diagnostics, prognostics, and the treatment of HNC. Moreover, phase I clinical trials suggest that gold nanoparticles are safe and can potentially become theranostic agents for humans.

Overview of mechanism and consequences of endothelial leakiness caused by metal and polymeric nanoparticles

Nanoparticles (NPs) exhibit unique physicochemical properties that enable them to overcome biological barriers and to be considered one of the best materials with anticancer properties. Most of the administered NPs that end up in the bloodstream interact with the endothelial layer. The interaction of the NPs with the endothelium widens the existing gaps or induces new ones in the monolayer of vascular endothelial cells, thus increasing the access to the target sites in the organism. This type of interaction can lead to NP-modulated endothelial leakiness (NanoEL). The most important factors determining NanoEL are the physicochemical properties of the NPs. NP-modulated endothelial leakiness can lead to the discovery of new therapeutic targets and strategies to improve drug delivery through controlling and regulating NanoEL. Nevertheless, the NanoEL mechanism also carries some limitations that result from an incomplete understanding of NP metabolism and toxicity, and the possibility of their participation in the unintended bidirectional vascular permeability, which may contribute to the formation of cancer metastases. In this review we are focusing on the effect of metal and polymeric NPs on mechanism and degree of induction of NanoEL, as well as on the benefits and risks of using NPs that induce endothelial leakiness.

Recent Advances in Green Metallic Nanoparticles for Enhanced Drug Delivery in Photodynamic Therapy: A Therapeutic Approach

Globally, cancer is one of the leading causes of death among men and women, it is characterized by the unregulated proliferation of tumor cells. Some of the common risk factors associated with cancer development include the consistent exposure of body cells to carcinogenic agents such as alcohol, tobacco, toxins, gamma rays and alpha particles. Besides the above-mentioned risk factors, conventional therapies such as radiotherapy, and chemotherapy have also been linked to the development of cancer. Over the past decade, tremendous efforts have been invested in the synthesis of eco-friendly green metallic nanoparticles (NPs), and their medical application. Comparatively, metallic NPs have greater advantages over conventional therapies. Additionally, metallic NPs can be functionalized with different targeting moieties e.g., liposomes, antibodies, folic acid, transferrin, and carbohydrates. Herein, we review and discuss the synthesis, and therapeutic potential of green synthesized metallic NPs for enhanced cancer photodynamic therapy (PDT). Finally, the advantages of green hybridized activatable NPs over conventional photosensitizers (PSs) and the future perspectives of nanotechnology in cancer research are discussed in the review. Furthermore, we anticipate that the insights offered in this review will inspire the design and development of green nano-formulations for enhanced image-guided PDT in cancer treatment.

Chemo-radiation therapy of U87-MG glioblastoma cells using SPIO@AuNP-Cisplatin-Alginate nanocomplex

Megavoltage radiotherapy and cisplatin-based chemotherapy are the primary glioblastoma treatments. Novel nanoparticles have been designed to reduce adverse effects and boost therapeutic effectiveness. In the present study, we synthesized the SPIO@AuNP-Cisplatin-Alginate (SACA) nanocomplex, composed of a SPIO core, a gold shell, and an alginate coating. SACA was characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS). U87-MG human glioblastoma cells and the HGF cell line (a healthy primary gingival fibroblast) were treated in multiple groups by a combination of SACA, cisplatin, and 6 MV X-ray. The MTT assay was used to assess the cytotoxicity of cisplatin and SACA (at various concentrations and for 4 h). Following the treatments, apoptosis and cell viability were evaluated in each treatment group using flow cytometry and the MTT assay, respectively. The findings demonstrated that the combination of SACA and 6 MV X-rays (at the doses of 2 and 4 Gy) drastically decreased the viability of U87MG cells, whereas the viability of HGF cells remained unchanged. Moreover, U87MG cells treated with SACA in combination with radiation exhibited a significant increase in apoptosis, demonstrating that this nanocomplex effectively boosted the radiosensitivity of cancer cells. Even though additional in vivo studies are needed, these findings suggest that SACA might be used as a radiosensitizer nanoparticle in the therapy of brain tumors.

Triphenylphosphonium conjugated gold nanotriangles impact Pi3K/AKT pathway in breast cancer cells: a photodynamic therapy approach

Although gold nanoparticles based photodynamic therapy (PDT) were reported to improve efficacy and specificity, the impact of surface charge in targeting cancer is still a challenge. Herein, we report gold nanotriangles (AuNTs) tuned with anionic and cationic surface charge conjugating triphenylphosphonium (TPP) targeting breast cancer cells with 5-aminoleuvinic acid (5-ALA) based PDT, in vitro. Optimized surface charge of AuNTs with and without TPP kill breast cancer cells. By combining, 5-ALA and PDT, the surface charge augmented AuNTs deliver improved cellular toxicity as revealed by MTT, fluorescent probes and flow cytometry. Further, the 5-ALA and PDT treatment in the presence of AuNTs impairs cell survival Pi3K/AKT signaling pathway causing mitochondrial dependent apoptosis. The cumulative findings demonstrate that, cationic AuNTs with TPP excel selective targeting of breast cancer cells in the presence of 5-ALA and PDT.

Tenofovir-tethered gold nanoparticles as a novel multifunctional long-acting anti-HIV therapy to overcome deficient drug delivery-: an in vivo proof of concept

BACKGROUND

The adoption of Antiretroviral Therapy (ART) substantially extends the life expectancy and quality of HIV-infected patients. Yet, eliminating the latent reservoirs of HIV to achieve a cure remains an unmet need. The advent of nanomedicine has revolutionized the treatment of HIV/AIDS. The present study explores a unique combination of Tenofovir (TNF) with gold nanoparticles (AuNPs) as a potential therapeutic approach to overcome several limitations of the current ART.

RESULTS

TNF-tethered AuNPs were successfully synthesized. Cell viability, genotoxicity, haemolysis, and histopathological studies confirmed the complete safety of the preparation. Most importantly, its anti-HIV1 reverse transcriptase activity was ~ 15 folds higher than the native TNF. In addition, it exhibited potent anti-HIV1 protease activity, a much sought-after target in anti-HIV1 therapeutics. Finally, the in vivo biodistribution studies validated that the AuNPs could reach many tissues/organs, serving as a secure nest for HIV and overcoming the problem of deficient drug delivery to HIV reservoirs.

CONCLUSIONS

We show that the combination of TNF and AuNPs exhibits multifunctional activity, viz. anti-HIV1 and anti-HIV1 protease. These findings are being reported for the first time and highlight the prospects of developing AuNP-TNF as a novel next-generation platform to treat HIV/AIDS.

Peptide mediated targeted delivery of gold nanoparticles into the demyelination site ameliorates myelin impairment and gliosis

Drug development for multiple sclerosis (MS) clinical management focuses on both neuroprotection and repair strategies, and is challenging due to low permeability of the blood-brain barrier, off-target distribution, and the need for high doses of drugs. The changes in the extracellular matrix have been documented in MS patients. It has been shown that the expression of nidogen-1 increases in MS lesions. Laminin forms a stable complex with nidogen-1 through a heptapeptide which was selected to target the lesion area in this study. Here we showed that the peptide binding was specific to the injured area following lysophosphatidylcholine (LPC) induced demyelination. In vivo data showed enhanced delivery of the peptide-functionalized gold nanoparticles (Pep-GNPs) to the lesion area. In addition, Pep-GNPs administration significantly enhanced myelin content and reduced astrocyte/microglia activation. Results demonstrated the possibility of using this peptide to target and treat lesions in patients suffering from MS.

Current advances in the application of nanomedicine in bladder cancer

Bladder cancer is the most common malignant tumor of the urinary system, however there are several shortcomings in current diagnostic and therapeutic measures. In terms of diagnosis, the diagnostic tools currently available are not sufficiently sensitive and specific, and imaging is poor, leading to misdiagnosis and missed diagnoses, which can delay treatment. In terms of treatment, current treatment options include surgery, chemotherapy, immunotherapy, gene therapy, and other emerging treatments, as well as combination therapies. However, the main reasons for poor efficacy and side effects during treatment are the lack of specificity and targeting, improper dose control of drugs and photosensitizers, damage to normal cells while attacking cancer cells, and difficulty in delivering siRNA to cancer cells. Nanomedicine is an emerging approach. Among the many nanotechnologies applied in the medical field, nanocarrier-assisted drug delivery systems have attracted extensive research interest due to their great translational value. Well-designed nanoparticles can deliver agents or drugs to specific cell types within target organs through active targeting or passive targeting (enhanced permeability and retention), which allows for imaging, diagnosis, as well as treatment of cancer. This paper reviews advances in the application of various nanocarriers and their advantages and drawbacks, with a focus on their use in the diagnosis and treatment of bladder cancer.

Engineering gold nanoparticles for molecular diagnostics and biosensing

Advances in nanotechnology and medical science have spurred the development of engineered nanomaterials and nanoparticles with particular focus on their applications in biomedicine. In particular, gold nanoparticles (AuNPs) have been the focus of great interest, due to their exquisite intrinsic properties, such as ease of synthesis and surface functionalization, tunable size and shape, lack of acute toxicity and favorable optical, electronic, and physicochemical features, which possess great value for application in biodetection and diagnostics purposes, including molecular sensing, photoimaging, and application under the form of portable and simple biosensors (e.g., lateral flow immunoassays that have been extensively exploited during the current COVID-19 pandemic). We shall discuss the main properties of AuNPs, their synthesis and conjugation to biorecognition moieties, and the current trends in sensing and detection in biomedicine and diagnostics. This article is categorized under: Diagnostic Tools > Biosensing Diagnostic Tools > In Vitro Nanoparticle-Based Sensing Diagnostic Tools > In Vivo Nanodiagnostics and Imaging.

Binding mechanism and SERS spectra of 5-fluorouracil on gold clusters

The adsorption behaviour of the 5-fluorouracil (5FU) on small gold clusters Au _N with N = 6, 8, 20 was evaluated by means of density functional theory using the PBE-D3 functional in combination with a mixed basis set, i.e. cc-pVDZ-PP for gold atoms and cc-pVTZ for non-metal elements. The binding energies between 5FU and gold clusters were determined in the range of 16-24 and 11-19 kcal/mol in gas-phase and aqueous media, respectively. The corresponding Gibbs energies were found to be around -7 to -10 kcal/mol in vacum and sigificantly reduced to -1 to -6 kcal/mol in water solution, indicating that both the association and dissociation processes are likely spontaneous. An analysis on the charge density difference tends to confirm the existence of a charge transfer from the 5FU molecule to Au atoms. Analysis of the surface-enhanced Raman scattering (SERS) spectra of 5FU adsorbed on the Au surfaces shows that the stretching vibrations of N-H and C=O bonds play a major role in the SERS phenomenon. A mechanism for the drug releasing from the gold surfaces is also proposed. The process is triggered by either the low pH in cancerous tumors or the presence of cysteine residues in protein matrices.