Comparison study on the effect of gold nanoparticles shape in the forms of star, hallow, cage, rods, and Si-Au and Fe-Au core-shell on photothermal cancer treatment

Localized surface plasmon energy dissipation in bimetallic core-shell nanostructures

Exploring the plasmon energy dissipation mechanism of bimetallic nanostructures after photoexcitation is of great significance for controlling energy transfer in plasmonic applications. The absorption, scattering, and extinction spectra of Ag@Cu, Ag@Pt, and Ag@Co core-shell nanostructures are calculated by finite element method, and the energy dissipation process is visualized by using particle trajectory and the absorbed power density distribution. The absorption/scattering ratio of the core-shell nanostructures, the shell absorptivity, the time-domain electric field as well as the extra-core electron arrangements of Ag, Cu, Pt, and Co atoms are analyzed for figuring out the energy dissipation mechanism. The results show that when a non-plasmonic metal is coated on the surface of a plasmonic metal, the plasmon energy dissipates preferentially in the shell, and the degree of dissipation depends on the imaginary part of the dielectric constant of the shell and the core. A larger dielectric constant of the shell can cause more energy to be transferred from the plasmonic metal to the shell region. This study provides the fundamental physical framework and design principles for plasmonic nanostructures.

Gold nanoparticles-mediated photothermal and photodynamic therapies for cancer

Cancer remains one of the major causes of death globally, with one out of every six deaths attributed to the disease. The impact of cancer is felt on psychological, physical, and financial levels, affecting individuals, communities, and healthcare institutions. Conventional cancer treatments have many challenges and inadequacies. Nanomedicine, however, presents a promising solution by not only overcoming these problems but also offering the advantage of combined therapy for treatment-resistant cancers. Nanoparticles specifically engineered for use in nanomedicine can be efficiently targeted to cancer cells through a combination of active and passive techniques, leading to superior tumor-specific accumulation, enhanced drug availability, and reduced systemic toxicity. Among various nanoparticle formulations designed for cancer treatment, gold nanoparticles have gained prominence in the field of nanomedicine due to their photothermal, photodynamic, and immunologic effects without the need for photosensitizers or immunotherapeutic agents. To date, there is no comprehensive literature review that focuses on the photothermal, photodynamic, and immunologic effects of gold nanoparticles. In this review, significant attention has been devoted to examining the parameters pertaining to the structure of gold nanoparticles and laser characteristics, which play a crucial role in influencing the efficacy of photothermal therapy (PTT) and photodynamic therapy (PDT). Moreover, this article provides insights into the success of PTT and PDT mediated by gold nanoparticles in primary cancer treatment, as well as the immunological effects of PTT and PDT on metastasis and recurrence, providing a promising strategy for cancer therapy. In summary, gold nanoparticles, with their unique properties, have the potential for clinical application in various cancer therapies, including the treatment of primary cancer, recurrence and metastasis.

Elastic Liposomes Containing Calcium/Magnesium Ferrite Nanoparticles Coupled with Gold Nanorods for Application in Photothermal Therapy

This work reports on the design, development, and characterization of novel magneto-plasmonic elastic liposomes (MPELs) of DPPC:SP80 (85:15) containing Mg0.75Ca0.25Fe2O4 nanoparticles coupled with gold nanorods, for topical application of photothermal therapy (PTT). Both magnetic and plasmonic components were characterized regarding their structural, morphological, magnetic and photothermal properties. The magnetic nanoparticles display a cubic shape and a size (major axis) of 37 ± 3 nm, while the longitudinal and transverse sizes of the nanorods are 46 ± 7 nm and 12 ± 1.6 nm, respectively. A new methodology was employed to couple the magnetic and plasmonic nanostructures, using cysteine as bridge. The potential for photothermia was evaluated for the magnetic nanoparticles, gold nanorods and the coupled magnetic/plasmonic nanoparticles, which demonstrated a maximum temperature variation of 28.9 °C, 33.6 °C and 37.2 °C, respectively, during a 30 min NIR-laser irradiation of 1 mg/mL dispersions. Using fluorescence anisotropy studies, a phase transition temperature (Tm) of 35 °C was estimated for MPELs, which ensures an enhanced fluidity crucial for effective crossing of the skin layers. The photothermal potential of this novel nanostructure corresponds to a specific absorption rate (SAR) of 616.9 W/g and a maximum temperature increase of 33.5 °C. These findings point to the development of thermoelastic nanocarriers with suitable features to act as photothermal hyperthermia agents.

Novel silicene-mesoporous silica nanoparticles conjugated gemcitabine induced cellular apoptosis via upregulating NF-κB p65 nuclear translocation suppresses pancreatic cancer growthin vitroandin vivo

Pancreatic cancer's high fatality rates stem from its resistance to systemic drug delivery and aggressive metastasis, limiting the efficacy of conventional treatments. In this study, two-dimensional ultrathin silicene nanosheets were initially synthesized and near-infrared-responsive two-dimensional silicene-mesoporous silica nanoparticles (SMSNs) were successfully constructed to load the clinically-approved conventional pancreatic cancer chemotherapeutic drug gemcitabine. Experiments on nanoparticle characterization show that they have excellent photothermal conversion ability and stability. Then silicene-mesoporous silica nanoparticles loaded with gemcitabine nanoparticles (SMSN@G NPs) were employed in localized photothermal therapy to control pancreatic tumor growth and achieve therapeutic effects. Our research confirmed the functionality of SMSN@G NPs through immunoblotting and apoptotic assays, demonstrating its capacity to enhance the nuclear translocation of the NF-κB p65, further affect the protein levels of apoptosis-related genes, induce the apoptosis of tumor cells, and ultimately inhibit the growth of the tumor. Additionally, the study assessed the inhibitory role of SMSN@G NPs on pancreatic neoplasm growthin vivo, revealing its excellent biocompatibility. SMSN@G NPs have a nice application prospect for anti-pancreatic tumors.

Phytosynthesis of gold-198 nanoparticles for a potential therapeutic radio-photothermal agent

We produced spherical gold-198 nanoparticles with an average size of 41 nm, good stability, and high radiochemical purity for a promising single agent of radio-photothermal therapy using Curcuma longa rhizome extract as a reducing and capping agent. The combination of in vitro treatment using gold-198 nanoparticles and irradiation of 980 nm wavelength lasers with a power output of 2 W/cm2 induced hyperthermia temperature and exhibited enhancement of the percentage dead on MDA-MB-123 cancer cells compared to gold-198 nanoparticles alone.

pH/redox responsive size-switchable intelligent nanovehicle for tumor microenvironment targeted DOX release

Tumor microenvironment (TME) targeted strategy could control the drug release in tumor cells more accurately and creates a new opportunity for enhanced site-specific targeted delivery. In this study, (PAA-b-PCL-S-S-PCL-b-PAA) copolymeric nanoparticles (NPs) with size-switchable ability and dual pH/redox-triggered drug release behavior were designed to significantly promote cancer uptake (cell internalization of around 100% at 30 min) and site-specific targeted doxorubicin (DOX) delivery in MDA-MB-231 tumor cells. NPs surface charge was shifted from - 17.8 to - 2.4 and their size shrunk from 170.3 to 93 nm in TME. The cell cycle results showed that DOX-loaded NPs showed G2/M (68%) arrest, while free DOX showed sub-G1 arrest (22%). Apoptosis tests confirmed that the cells treated with DOX-loaded NPs showed a higher amount of apoptosis (71.6%) than the free DOX (49.8%). Western blot and RT-PCR assays revealed that the apoptotic genes and protein levels were significantly upregulated using the DOX-loaded NPs vs. the free DOX (Pvalue < 0.001). In conclusion, dual pH/redox-responsive and size-switchable DOX-loaded NPs developed here showed outstanding anti-tumoral features compared with free DOX that might present a prospective platform for tumor site-specific accumulation and drug release that suggest further in vivo research.

The Refined Application and Evolution of Nanotechnology in Enhancing Radiosensitivity During Radiotherapy: Transitioning from Gold Nanoparticles to Multifunctional Nanomaterials

Radiotherapy is a pivotal method for treating malignant tumors, and enhancing the therapeutic gain ratio of radiotherapy through physical techniques is the direction of modern precision radiotherapy. Due to the inherent physical properties of high-energy radiation, enhancing the therapeutic gain ratio of radiotherapy through radiophysical techniques inevitably encounters challenges. The combination of hyperthermia and radiotherapy can enhance the radiosensitivity of tumor cells, reduce their radioresistance, and holds significant clinical utility in radiotherapy. Multifunctional nanomaterials with excellent biocompatibility and safety have garnered widespread attention in tumor hyperthermia research, demonstrating promising potential. Utilizing nanotechnology as a sensitizing carrier in conjunction with radiotherapy, and high atomic number nanomaterials can also serve independently as radiosensitizing carriers. This synergy between tumor hyperthermia and radiotherapy may overcome many challenges currently limiting tumor radiotherapy, offering new opportunities for its further advancement. In recent years, the continuous progress in the synthesis and design of novel nanomaterials will propel the future development of medical imaging and cancer treatment. This article summarizes the radiosensitizing mechanisms and effects based on gold nanotechnology and provides an overview of the advancements of other nanoparticles (such as bismuth-based nanomaterials, magnetic nanomaterials, selenium nanomaterials, etc.) in the process of radiation therapy.

Critical parameters to translate gold nanoparticles as radiosensitizing agents into the clinic

Radiotherapy is an inevitable choice for cancer treatment that is applied as combinatorial therapy along with surgery and chemotherapy. Nevertheless, radiotherapy at high doses kills normal and tumor cells at the same time. In addition, some tumor cells are resistant to radiotherapy. Recently, many researchers have focused on high-Z nanomaterials as radiosensitizers for radiotherapy. Among them, gold nanoparticles (GNPs) have shown remarkable potential due to their promising physical, chemical, and biological properties. Although few clinical trial studies have been performed on drug delivery and photosensitization with lasers, GNPs have not yet received Food and Drug Administration approval for use in radiotherapy. The sensitization effects of GNPs are dependent on their concentration in cells and x-ray energy deposition during radiotherapy. Notably, some limitations related to the properties of the GNPs, including their size, shape, surface charge, and ligands, and the radiation source energy should be resolved. At the first, this review focuses on some of the challenges of using GNPs as radiosensitizers and some biases among in vitro/in vivo, Monte Carlo, and clinical studies. Then, we discuss the challenges in the clinical translation of GNPs as radiosensitizers for radiotherapy and proposes feasible solutions. And finally, we suggest that certain areas be considered in future research. This article is categorized under: Therapeutic Approaches and Drug Discovery > NA.

Shape-Driven Response of Gold Nanoparticles to X-rays

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

Cancer Treatment Using Different Shapes of Gold-Based Nanomaterials in Combination with Conventional Physical Techniques

The conventional methods of cancer treatment and diagnosis, such as radiotherapy, chemotherapy, and computed tomography, have developed a great deal. However, the effectiveness of such methods is limited to the possible failure or collateral effects on the patients. In recent years, nanoscale materials have been studied in the field of medical physics to develop increasingly efficient methods to treat diseases. Gold nanoparticles (AuNPs), thanks to their unique physicochemical and optical properties, were introduced to medicine to promote highly effective treatments. Several studies have confirmed the advantages of AuNPs such as their biocompatibility and the possibility to tune their shapes and sizes or modify their surfaces using different chemical compounds. In this review, the main properties of AuNPs are analyzed, with particular focus on star-shaped AuNPs. In addition, the main methods of tumor treatment and diagnosis involving AuNPs are reviewed.

Light-related activities of metal-based nanoparticles and their implications on dermatological treatment

Metal-based nanoparticles (MNPs) represent an emerging class of materials that have attracted enormous attention in many fields. By comparison with other biomaterials, MNPs own unique optical properties which make them a potential alternative to conventional therapeutic agents in medical applications. Especially, owing to the easy access to the skin, the use of MNPs based on their optical properties has gained importance for the treatment of a variety of skin diseases. This review provides an insight into the different optical properties of MNPs, including photoprotection, photocatalysis, and photothermal, and highlights their implications in treating skin disorders, with a special emphasis on their use in infection control. Finally, a perspective on the safety concern of MNPs for dermatological use is discussed and analyzed. The information gathered and presented in this review will help the readers have a comprehensive understanding of utilizing the photo-triggered activity of MNPs for the treatment of skin diseases.

Synergistic chemotherapy and phototherapy based on red blood cell biomimetic nanomaterials

Novel drug delivery systems (DDSs) have become the mainstay of research in targeted cancer therapy. By combining different therapeutic strategies, potential DDSs and synergistic treatment approaches are needed to effectively deal with evolving drug resistance and the adverse effects of cancer. Nowadays, developing and optimizing human cell-based DDSs has become a new research strategy. Among them, red blood cells can be used as DDSs as they significantly enhance the pharmacokinetics of the transported drug cargo. Phototherapy, as a novel adjuvant in cancer treatment, can be divided into photodynamic therapy and photothermal therapy. Phototherapy using erythropoietic nanocarriers to mimic the unique properties of erythrocytes and overcome the limitations of existing DDSs shows excellent prospects in clinical settings. This review provides an overview of the development of photosensitizers and research on bio-nano-delivery systems based on erythrocytes and erythrocyte membranes that are used in achieving synergistic outcomes during phototherapy/chemotherapy.

A novel vector for magnetic resonance imaging-guided chemo-photothermal therapy for cancer

As an effective strategy for oncotherapy, developing efficacious drug delivery systems for cancer combination therapy remains a major challenge. To improve nanodrug biocompatibility and composite function facilitating their clinical conversion application, a novel nanocarrier was presented by a facile method through conjugating humic acid with gadolinium ions to synthesize HA-Gd with good biocompatibility and dispersity. HA-Gd exhibited high photothermal conversion efficiency up to 38%, excellent photothermal stability, and high doxorubicin (DOX) loading capacity (93%) with pH-responsive release properties. HA-Gd loading DOX showed a combined chemo-photothermal inhibitory effect on tumor cells. Compared with lipid-DOX, HA-Gd-DOX had a more significant inhibitory effect on tumor growth and fewer side effects. T1-weighted MRI contrast toward tumor tissue provided HA-Gd with an MRI-based cancer diagnosis. This study revealed the great potential of humic acids as a novel vector for developing more drug carriers with desirable functions for clinical anticancer therapy.

AuNP/Chitosan Nanocomposites Synthesized through Plasma Induced Liquid Chemistry and Their Applications in Photothermal Induced Bacteria Eradication

In this work, a facile direct current atmospheric pressure micro-plasma (APM) technology was deployed for the synthesis of functional gold nanoparticle/chitosan (AuNP/CS) nanocomposites for the first time. Different experimental parameters, such as metal salt precursor concentration and chitosan viscosity, have been investigated to understand their effects on the resulting nanocomposite structures and properties. The nanocomposites were fully characterized using a wide range of material characterization techniques such as UV–vis, transmission electron microscope (TEM), Fourier transform infrared (FTIR) spectra and X-ray photoelectron spectroscopy (XPS) analyses. Potential reaction pathways have been proposed for the nanocomposite synthesis process. Finally, potential of the synthesized nanocomposites towards photothermal conversion and bacteria eradiation applications has been demonstrated. The results show that APM is a facile, rapid and versatile technique for the synthesis of AuNP/CS functional nanocomposites. Through this work, a more in-depth understanding of the multi-phase system (consisting of gas, plasma, liquid and solid) has been established and such understanding could shine a light on the future design and fabrication of new functional nanocomposites deploying the APM technique.

Gold Nanorod-Assisted Photothermal Therapy and Improvement Strategies

Noble metal nanoparticles have been sought after in cancer nanomedicine during the past two decades, owing to the unique localized surface plasmon resonance that induces strong absorption and scattering properties of the nanoparticles. A popular application of noble metal nanoparticles is photothermal therapy, which destroys cancer cells by heat generated by laser irradiation of the nanoparticles. Gold nanorods have stood out as one of the major types of noble metal nanoparticles for photothermal therapy due to the facile tuning of their optical properties in the tissue penetrative near infrared region, strong photothermal conversion efficiency, and long blood circulation half-life after surface modification with stealthy polymers. In this review, we will summarize the optical properties of gold nanorods and their applications in photothermal therapy. We will also discuss the recent strategies to improve gold nanorod-assisted photothermal therapy through combination with chemotherapy and photodynamic therapy.

Nanomedicine in Clinical Photodynamic Therapy for the Treatment of Brain Tumors

The current treatment for malignant brain tumors includes surgical resection, radiotherapy, and chemotherapy. Nevertheless, the survival rate for patients with glioblastoma multiforme (GBM) with a high grade of malignancy is less than one year. From a clinical point of view, effective treatment of GBM is limited by several challenges. First, the anatomical complexity of the brain influences the extent of resection because a fine balance must be struck between maximal removal of malignant tissue and minimal surgical risk. Second, the central nervous system has a distinct microenvironment that is protected by the blood–brain barrier, restricting systemically delivered drugs from accessing the brain. Additionally, GBM is characterized by high intra-tumor and inter-tumor heterogeneity at cellular and histological levels. This peculiarity of GBM-constituent tissues induces different responses to therapeutic agents, leading to failure of targeted therapies. Unlike surgical resection and radiotherapy, photodynamic therapy (PDT) can treat micro-invasive areas while protecting sensitive brain regions. PDT involves photoactivation of photosensitizers (PSs) that are selectively incorporated into tumor cells. Photo-irradiation activates the PS by transfer of energy, resulting in production of reactive oxygen species to induce cell death. Clinical outcomes of PDT-treated GBM can be advanced in terms of nanomedicine. This review discusses clinical PDT applications of nanomedicine for the treatment of GBM.

Gold Nanomaterials as a Promising Integrated Tool for Diagnosis and Treatment of Pathogenic Infections-A Review

This review summarizes research on functionalized gold nanomaterials as pathogen detection sensors and pathogen elimination integrated tools. After presenting the challenge of current severe threat from pathogenic bacteria and the increasingly serious growth rate of drug resistance, the first section mainly introduces the conspectus of gold nanostructures from synthesis, characterization, physicochemical properties and applications of gold nanomaterials. The next section deals with gold nanomaterials-based pathogen detection sensors such as colorimetric sensors, fluorescence sensors and Surface-Enhanced Raman Scattering sensors. We then discuss strategies based on gold nanomaterials for eliminating pathogenic infections, such as the dual sterilization strategy for grafting gold nanomaterials with antibacterial substances, photothermal antibacterial and photodynamic antibacterial methods. The fourth part briefly introduces the comprehensive strategy for diagnosis and sterilization of pathogen infection based on gold nanomaterials, such as the diagnosis and treatment strategy for pathogen infection using Roman signals real-time monitoring and photothermal sterilization. A concluding section that summarizes the current status and challenges of the novel diagnosis and treatment integrated strategy for pathogenic infections, gives an outlook on potential future perspectives.

Au Catalyzing Control Release NO in vivo and Tumor Growth-Inhibiting Effect in Chemo-Photothermal Combination Therapy

INTRODUCTION

Aim to obtain a NO donor that can control released NO in vivo with the high efficacy of tumor suppression and targeting, a nanoplatform consisting of FA-Fe3O4@mSiO2-Au/DOX was constructed.

METHODS

In vitro, the nanoplatform catalyzed NO's release with the maximum value of 4.91 μM within 60 min at 43°C pH=5.0, which was increased by 1.14 times when the temperature was 37°C. In vivo, 11.7 μg Au in the tumor tissue was found to catalyze S-nitrosoglutathione continuously, and 54 μM NO was checked out in the urine.

RESULTS AND DISCUSSION

The high concentration of NO was found to increase the apoptotic rate and to reduce tumor proliferation. In the chemo-photothermal combination therapy, the tumor inhibition rate was increased up to 94.3%, and Au's contribution from catalyzing NO release NO was 8.17%.