Gold Nanostars Embedded in PDMS Films: A Photothermal Material for Antibacterial Applications

Bacteria infections and related biofilms growth on surfaces of medical devices are a serious threat to human health. Controlled hyperthermia caused by photothermal effects can be used to kill bacteria and counteract biofilms formation. Embedding of plasmonic nano-objects like gold nanostars (GNS), able to give an intense photothermal effect when irradiated in the NIR, can be a smart way to functionalize a transparent and biocompatible material like polydimethylsiloxane (PDMS). This process enables bacteria destruction on surfaces of PDMS-made medical surfaces, an action which, in principle, can also be exploited in subcutaneous devices. We prepared stable and reproducible thin PDMS films containing controllable quantities of GNS, enabling a temperature increase that can reach more than 40 degrees. The hyperthermia exerted by this hybrid material generates an effective thermal microbicidal effect, killing bacteria with a near infrared (NIR) laser source with irradiance values that are safe for skin.

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Fabrication of photothermally active poly(vinyl alcohol) films with gold nanostars for antibacterial applications

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.193 ◽

2018 ◽

Vol 9 ◽

pp. 2040-2048 ◽

Cited By ~ 14

Author(s):

Mykola Borzenkov ◽

Maria Moros ◽

Claudia Tortiglione ◽

Serena Bertoldi ◽

Nicola Contessi ◽

...

Keyword(s):

Mechanical Properties ◽

Vinyl Alcohol ◽

Near Infrared ◽

Polymeric Materials ◽

Photothermal Effect ◽

Poly Vinyl Alcohol ◽

Broad Application ◽

Gold Nanostars ◽

Wide Range ◽

Spherical Gold Nanoparticles

The unique photothermal properties of non-spherical gold nanoparticles under near-infrared (NIR) irradiation find broad application in nanotechnology and nanomedicine. The combination of their plasmonic features with widely used biocompatible poly(vinyl alcohol) (PVA) films can lead to novel hybrid polymeric materials with tunable photothermal properties and a wide range of applications. In this study, thin PVA films containing highly photothermally efficient gold nanostars (GNSs) were fabricated and their properties were studied. The resulting films displayed good mechanical properties and a pronounced photothermal effect under NIR irradiation. The local photothermal effect triggered by NIR irradiation of the PVA-GNS films is highly efficient at killing bacteria, therefore providing an opportunity to develop new types of protective antibacterial films and coatings.

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Safety Considerations for Sample Analysis Using a Near-Infrared (785 nm) Raman Laser Source

Applied Spectroscopy ◽

10.1366/000370203321666632 ◽

2003 ◽

Vol 57 (5) ◽

pp. 580-587 ◽

Cited By ~ 16

Author(s):

S. D. Harvey ◽

T. J. Peters ◽

B. W. Wright

Keyword(s):

Near Infrared ◽

Energetic Material ◽

Experimental Studies ◽

Thermal Response ◽

Raman Laser ◽

Medical Diagnostics ◽

Laser Source ◽

Analytical Technique ◽

Nir Laser

Raman spectroscopy is often considered a nondestructive analytical technique; however, this is not always the case. The 300-mW 785-nm near-infrared (NIR) laser source used with many commercially available instruments has sufficient power to burn samples. This destructive potential is of special concern if the sample is irreplaceable (e.g., fine art, forensic evidence, or for in vivo medical diagnostics) or a hazardous energetic material (explosive or pyrophoric samples). This study quantifies the heat resulting from illuminating an extensive color array with a 785-nm NIR laser and relates these values to the hazards associated with Raman analysis. In general, darker colors were found to be more problematic. Since visible colors are not ideally correlated with absorptive characteristics at 785 nm, predictions based on thermography are not perfect; however, this approximation gives a useful method for predicting the thermal response of unknown samples to NIR exposure. Additionally, experimental studies evaluated the analysis of flammable organic solvents, propellants, military explosives, mixtures containing military explosives, shock-sensitive explosives, and gunpowders (i.e., smokeless, black, and Pyrodex powders). Safety guidelines for analysis are presented.

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Near-Infrared Fluorescent Sorbitol Probe for Targeted Photothermal Cancer Therapy

Cancers ◽

10.3390/cancers11091286 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1286 ◽

Cited By ~ 6

Author(s):

Lee ◽

Jung ◽

Jo ◽

Yang ◽

Koh ◽

...

Keyword(s):

Cancer Therapy ◽

Laser Irradiation ◽

Near Infrared ◽

Photothermal Effect ◽

Great Promise ◽

Targeted Cancer Therapy ◽

Potential Applications ◽

Photothermal Property ◽

Nir Laser

Abstract: Photothermal therapy (PTT) using a near-infrared (NIR) heptamethine cyanine fluorophore has emerged as an alternative strategy for targeted cancer therapy. NIR fluorophores showing a high molar extinction coefficient and low fluorescence quantum yield have considerable potential applications in photothermal cancer therapy. In this study, a bifunctional sorbitol–ZW800 conjugate was used as an advanced concept of photothermal therapeutic agents for in vivo cancer imaging and therapy owing to the high tumor targetability of the sorbitol moiety and excellent photothermal property of NIR heptamethine cyanine fluorophore. The sorbitol–ZW800 showed an excellent photothermal effect increased by 58.7 °C after NIR laser irradiation (1.1 W/cm2) for 5 min. The HT-29 tumors targeted by sorbitol–ZW800 showed a significant decrease in tumor volumes for 7 days after photothermal treatment. Therefore, combining the bifunctional sorbitol–ZW800 conjugate and NIR laser irradiation is an alternative way for targeted cancer therapy, and this approach holds great promise as a safe and highly efficient NIR photothermal agent for future clinical applications.

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Stimuli-responsive graphene oxide and methotrexate-loaded magnetic nanoparticles for breast cancer-targeted therapy

Nanomedicine ◽

10.2217/nnm-2021-0094 ◽

2021 ◽

Vol 16 (24) ◽

pp. 2155-2174

Author(s):

Mitra Dolatkhah ◽

Nastaran Hashemzadeh ◽

Jaleh Barar ◽

Khosro Adibkia ◽

Ayuob Aghanejad ◽

...

Keyword(s):

Breast Cancer ◽

Graphene Oxide ◽

Near Infrared ◽

Folate Receptor ◽

Superparamagnetic Iron Oxide ◽

Photothermal Effect ◽

Breast Cancer Cell Lines ◽

Stimuli Responsive ◽

High Cytotoxicity ◽

Nir Laser

Aim: Nanocomposites of graphene oxide (GO) loaded with PEGylated superparamagnetic iron oxide nanoparticles and grafted with methotrexate and stimuli-responsive linkers (GO-SPION-MTX) were developed for photothermal and chemotherapy of breast cancer. Methods: PEGylated SPIONs were synthesized and conjugated with chemotherapeutic targeting agent MTX, which were then loaded on GO to prepare GO-SPION-MTX nanocomposites. To evaluate the photothermal effect of the nanocomposites, they were examined in breast cancer cell lines with low doses of near-infrared (NIR) laser radiation with/without acetazolamide. Results: The GO-SPION-MTX nanocomposites were found to be internalized by the folate-receptor-positive cancer cells and induce high cytotoxicity on exposure to NIR laser rays. Conclusion: Our findings suggest that the GO-SPION-MTX nanocomposite can potentially be used as a multimodal nanomedicine/theranostic against breast cancer.

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Indocyanine Green and Methyl-β-Cyclodextrin Complex for Enhanced Photothermal Cancer Therapy

Biomedicines ◽

10.3390/biomedicines8110476 ◽

2020 ◽

Vol 8 (11) ◽

pp. 476 ◽

Cited By ~ 1

Author(s):

Gayoung Jo ◽

Bo Young Lee ◽

Eun Jeong Kim ◽

Min Ho Park ◽

Hoon Hyun

Keyword(s):

Cancer Therapy ◽

Indocyanine Green ◽

Laser Irradiation ◽

Near Infrared ◽

Body Weight Loss ◽

Photothermal Effect ◽

Cyclodextrin Complex ◽

Photothermal Treatment ◽

Potential Strategy ◽

Nir Laser

A feasible and biocompatible supramolecular complex self-assembled from indocyanine green (ICG) and methyl-β-cyclodextrin (Mβ-CD) was developed for targeted cancer imaging, which enhanced fluorescence-guided photothermal cancer therapy. This study confirmed that the formation of an inclusion complex of the heterocyclic ICG moiety and Mβ-CD inner cavity could result in improved tumor targetability compared with free ICG. The ICG-CD complex could be used as a bifunctional phototherapeutic agent for targeted cancer phototherapy due to the high tumor targetability of the Mβ-CD moiety and effective photothermal performance of the near-infrared (NIR) ICG moiety. Upon NIR laser irradiation, the photothermal effect exerted by the ICG-CD complex significantly enhanced the temperature at the tumor site by 56.2 °C within 5 min. Targeting HT-29 tumors using the ICG-CD complex resulted in an apparent reduction in tumor volumes over the 9 days after photothermal treatment. Moreover, no tumor recurrence or body weight loss were observed after administering a single dose of ICG-CD complex with NIR laser irradiation. Therefore, the administration of the biocompatible ICG-CD complex in combination with NIR laser treatment can be safely explored as a potential strategy for future clinical applications.

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Synthesis of Cu2(OH)PO4 superstructures with NIR-laser enhanced photocatalytic activity

Functional Materials Letters ◽

10.1142/s1793604720500150 ◽

2020 ◽

Vol 13 (03) ◽

pp. 2050015 ◽

Cited By ~ 1

Author(s):

Lu Cheng ◽

Nuo Yu ◽

Yan Zhang ◽

Zhun Shi ◽

Haifeng Wang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Near Infrared ◽

Visible Region ◽

Photogenerated Electron ◽

Photothermal Effect ◽

Hydrothermal Route ◽

Electron Hole ◽

Light Group ◽

Nir Laser

The development of photocatalysts with wide UV-Vis-near-infrared (NIR) photoabsorption has received tremendous interest for utilizing sunlight efficiently. In this work, Cu2(OH)PO4 superstructures are prepared by a simple hydrothermal route, and they have strong bandgap absorption in UV-Visible region and a distinctive plasmon resonance absorption in NIR region. Under the synergetic illumination of visible light and 980[Formula: see text]nm laser (3.0[Formula: see text]W[Formula: see text]cm[Formula: see text]), Cu2(OH)PO4 superstructures can degrade 89.2% MB with the elevated temperature ([Formula: see text]51∘C) of solution, which is higher than that from visible light group (50.0%), laser group (16.4%), and visible-light/exterior-heating group (62.5%, same temperature at [Formula: see text]51.0∘C). These facts reveal that Cu2(OH)PO4 superstructures exhibit NIR-laser enhanced photocatalytic activity, which not only comes from the photothermal effect-induced temperature elevation, but also mainly results from the increased production of photogenerated electron-hole pairs by NIR-laser. Therefore, Cu2(OH)PO4 superstructures can act as efficient photocatalyst with NIR-laser enhanced photocatalytic activity.

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Intercellular Trafficking of Gold Nanostars in Uveal Melanoma Cells for Plasmonic Photothermal Therapy

Nanomaterials ◽

10.3390/nano10030590 ◽

2020 ◽

Vol 10 (3) ◽

pp. 590 ◽

Cited By ~ 2

Author(s):

Rubén Ahijado-Guzmán ◽

Natalia Sánchez-Arribas ◽

María Martínez-Negro ◽

Guillermo González-Rubio ◽

María Santiago-Varela ◽

...

Keyword(s):

Cell Division ◽

Cancer Cells ◽

Uveal Melanoma ◽

Near Infrared ◽

Melanoma Cells ◽

Photothermal Effect ◽

Plasmonic Nanostructures ◽

Electromagnetic Spectrum ◽

Pulse Laser Irradiation ◽

Gold Nanostars

Efficient plasmonic photothermal therapies (PPTTs) using non-harmful pulse laser irradiation at the near-infrared (NIR) are a highly sought goal in nanomedicine. These therapies rely on the use of plasmonic nanostructures to kill cancer cells while minimizing the applied laser power density. Cancer cells have an unsettled capacity to uptake, retain, release, and re-uptake gold nanoparticles, thus offering enormous versatility for research. In this work, we have studied such cell capabilities for nanoparticle trafficking and its impact on the effect of photothermal treatments. As our model system, we chose uveal (eye) melanoma cells, since laser-assisted eye surgery is routinely used to treat glaucoma and cataracts, or vision correction in refractive surgery. As nanostructure, we selected gold nanostars (Au NSs) due to their high photothermal efficiency at the near-infrared (NIR) region of the electromagnetic spectrum. We first investigated the photothermal effect on the basis of the dilution of Au NSs induced by cell division. Using this approach, we obtained high PPTT efficiency after several cell division cycles at an initial low Au NS concentration (pM regime). Subsequently, we evaluated the photothermal effect on account of cell division upon mixing Au NS-loaded and non-loaded cells. Upon such mixing, we observed trafficking of Au NSs between loaded and non-loaded cells, thus achieving effective PPTT after several division cycles under low irradiation conditions (below the maximum permissible exposure threshold of skin). Our study reveals the ability of uveal melanoma cells to release and re-uptake Au NSs that maintain their plasmonic photothermal properties throughout several cell division cycles and re-uptake. This approach may be readily extrapolated to real tissue and even to treat in situ the eye tumor itself. We believe that our method can potentially be used as co-therapy to disperse plasmonic gold nanostructures across affected tissues, thus increasing the effectiveness of classic PPTT.

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Hyperthermia Induced by Near-Infrared Laser-Irradiated CsWO3 Nanoparticles Disintegrates Preformed Lysozyme Amyloid Fibrils

Nanomaterials ◽

10.3390/nano10030442 ◽

2020 ◽

Vol 10 (3) ◽

pp. 442

Author(s):

Po-Sheng Hu ◽

Natalia Tomasovicova ◽

Hsiu-Jen Chou ◽

Meng-Chang Li ◽

Marek Vojtko ◽

...

Keyword(s):

Electron Microscopy ◽

Near Infrared ◽

Amyloid Fibrils ◽

Research Study ◽

Photothermal Effect ◽

Force Microscopy ◽

Atomic Force ◽

Dendritic Structures ◽

Nir Laser ◽

Scanning Electron

This research study attempts to prove the concept of the applicability of hyperthermia to treating the lysozyme amyloid fibrils (LAFs)’s self-assembled fibrillary aggregates by a feedback-modulated temperature controller ranging from 26 °C to 80 °C, and separately, by near-infrared (NIR) laser-irradiated cesium tungstate (CsWO3) nanoparticle (NPs). The dependence of the final morphology of the amyloidal assembly on external heating and the photothermal effect of the NPs on treating the fibrillary assembly were investigated and analyzed. Experimentally, atomic force microscopy (AFM), optical stereoscopy, and scanning electron microscopy (SEM) were used primarily to ensure mutual interaction between LAFs and NPs, optically elucidate the surface contour and final fibrillary assembly upon the influence of thermal treatment, and further reveal fine-details of the optical samples. Finally, conclusive remarks are drawn that the fibrillary structures doped with the NPs exhibit an increasing degree of unique orthogonality. As the temperature rises, utter deformation of the dendritic structures of fibrillary assemblies at 70 °C was found, and NIR laser-irradiated CsWO3 NPs have been demonstrated to be useful in topically destructing pre-assembled LAFs, which may be conducive to the future development of neurodegenerative therapeutic techniques.

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Gold Nanorod-Mediated Photothermal Modulation for Localized Ablation of Cancer Cells

Journal of Nanomaterials ◽

10.1155/2012/825060 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

Yoochan Hong ◽

Eugene Lee ◽

Jihye Choi ◽

Seung Jae Oh ◽

Seungjoo Haam ◽

...

Keyword(s):

Cancer Cells ◽

Laser Power ◽

Near Infrared ◽

Gold Nanorod ◽

Photothermal Effect ◽

Transduction Efficiency ◽

Dead Cell ◽

Photothermal Ablation ◽

Power Densities ◽

Nir Laser

We estimated the photothermal transduction efficiency of gold nanorod (GNR) solutions for different GNR concentrations and irradiation laser power. In particular, we verified that the degree of cell death area could be modulated by GNR concentration and irradiation laser power. The efficacy of GNR-produced photothermal ablation of cancer cells was evaluated by irradiating GNRs in the presence of MDA-MB-231 breast cancer cells with a near-infrared (NIR) laser at different laser power densities and irradiation times. GNR-induced photothermal ablation was applied successfully to cancer cells at various NIR laser power densities and irradiation times and was characterized with live-dead cell staining. Through these techniques, we established the system for not only verification of induced photothermal effect using NIR laser and thermocouple, but also identification of uptake efficiency for GNRs and cell viability using dark field and fluorescence imaging, respectively.

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