Near-infrared-light-induced decomposition of Rhodamine B triggered by localized surface plasmon at gold square dimers with well-defined separation distance

Diffuse optical tomography uses near-infrared light spectroscopy to measure changes in cerebral hemoglobin concentration. Anatomical interpretations of the location that generates the hemodynamic signal requires accurate descriptions of diffuse optical tomography sensitivity to the underlying cortical structures. Such information is limited for pediatric populations because they undergo rapid head and brain development. The present study used photon propagation simulation methods to examine diffuse optical tomography sensitivity profiles in realistic head models among infants ranging from 2 weeks to 24 months with narrow age bins, children (4 and 12 years) and adults (20 to 24 years). The sensitivity profiles changed systematically with the source-detector separation distance. The peak of the sensitivity function in the head was largest at the smallest separation distance and decreased as separation distance increased. The fluence value dissipated more quickly with sampling depth at the shorter source-detector separations than the longer separation distances. There were age-related differences in the shape and variance of sensitivity profiles across a wide range of source-detector separation distances. Our findings have important implications in the design of sensor placement and diffuse optical tomography image reconstruction in (functional) near-infrared light spectroscopy research. Age-appropriate realistic head models should be used to provide anatomical guidance for standalone near-infrared light spectroscopy data in infants.

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In vivo Monitoring of Gold Nanorods and Tissue Damage Mediated with Their Photothermal Effect

MRS Proceedings ◽

10.1557/proc-1138-ff07-08 ◽

2008 ◽

Vol 1138 ◽

Author(s):

Takuro Niidome ◽

Yasuyuki Akiyama ◽

Kohei Shimoda ◽

Takahito Kawano ◽

Takeshi Mori ◽

...

Keyword(s):

Surface Plasmon ◽

Gold Nanorods ◽

Near Infrared ◽

Tumor Therapy ◽

Infrared Light ◽

Photothermal Effect ◽

Integrating Sphere ◽

Plasmon Band ◽

Near Infrared Light

AbstractGold nanorods have a strong surface plasmon band at the near infrared region. The absorbed light energy is then converted to heat. Since near infrared light can penetrate deeply into tissue, gold nanorods are expected to be used as a contrast agent for bioimaging using the near infrared light and photosensitizers for photothermal therapy. The surface plasmon bands of intravenously injected the gold nanorods were directly monitored from the mouse abdomen by using a spectrophotometer equipped with an integrating sphere. The absorbance at 900 nm from PEG5,000-modified gold nanorods immediately increased after injection and reached a plateau. The injection of phosphatidylcholine-modified gold nanorods also increased the absorbance at 900 nm, but the absorbance decreased single exponentially with a 1.3-min half-life. To demonstrate photothermal tumor therapy, the PEG-modified gold nanorods were directly injected into subcutaneous tumors in mice, then, near infrared laser light was irradiated to the tumor. After the treatment, significant suppression of tumor growth was observed.

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Synthesis of visible and near‐infrared light responsed Sn 1− x Bi x S 2 for efficient degradation of high concentration rhodamine B

Micro & Nano Letters ◽

10.1049/mnl.2017.0727 ◽

2018 ◽

Vol 13 (4) ◽

pp. 427-431

Author(s):

Hui Li ◽

Xiang‐Feng Wu ◽

Mai‐Tuo Yu ◽

Yi‐Jin Wang ◽

Chen‐Xu Zhang ◽

...

Keyword(s):

Rhodamine B ◽

Near Infrared ◽

Infrared Light ◽

High Concentration ◽

Near Infrared Light

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Photocurrent generation of a porphyrin self-assembly monolayer on a gold film electrode by surface plasmon excitation using near-infrared light

Chemical Physics Letters ◽

10.1016/s0009-2614(00)00393-6 ◽

2000 ◽

Vol 322 (3-4) ◽

pp. 242-246 ◽

Cited By ~ 20

Author(s):

Akito Ishida ◽

Tetsuro Majima

Keyword(s):

Surface Plasmon ◽

Self Assembly ◽

Near Infrared ◽

Gold Film ◽

Infrared Light ◽

Film Electrode ◽

Plasmon Excitation ◽

Near Infrared Light ◽

Photocurrent Generation ◽

Surface Plasmon Excitation

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Recent Advances in Hollow Gold Nanostructures for Biomedical Applications

Frontiers in Chemistry ◽

10.3389/fchem.2021.699284 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jeong-Min Park ◽

Hye Eun Choi ◽

Dauletkerey Kudaibergen ◽

Jae-Hyuk Kim ◽

Ki Su Kim

Keyword(s):

Drug Delivery ◽

Surface Plasmon ◽

Metallic Nanoparticles ◽

Biomedical Applications ◽

Near Infrared ◽

Synthetic Methods ◽

Gold Nanostructures ◽

Infrared Light ◽

Localized Surface Plasmon ◽

Recent Advances

The localized surface plasmon resonance of metallic nanoparticles has attracted much attention owing to its unique characteristics, including the enhancement of signals in sensors and photothermal effects. In particular, hollow gold nanostructures are highly promising for practical applications, with significant advantages being found in their material properties and structures: 1) the interaction between the outer surface plasmon mode and inner cavity mode leads to a greater resonance, allowing it to absorb near-infrared light, which can readily penetrate tissue; 2) it has anti-corrosiveness and good biocompatibility, which makes it suitable for biomedical applications; 3) it shows a reduced net density and large surface area, allowing the possibility of nanocarriers for drug delivery. In this review, we present information on the classification, characteristics, and synthetic methods of hollow gold nanostructures; discuss the recent advances in hollow gold nanostructures in biomedical applications, including biosensing, bioimaging, photothermal therapy, and drug delivery; and report on the existing challenges and prospects for hollow gold nanostructures.

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