scholarly journals Designing highly emissive over-1000 nm near-infrared fluorescent dye-loaded polystyrene-based nanoparticles for in vivo deep imaging

RSC Advances ◽  
2021 ◽  
Vol 11 (31) ◽  
pp. 18930-18937
Author(s):  
Yuichi Ueya ◽  
Masakazu Umezawa ◽  
Eiji Takamoto ◽  
Moe Yoshida ◽  
Hisanori Kobayashi ◽  
...  
Keyword(s):  
Optical Properties ◽  
Acrylic Acid ◽  
Near Infrared ◽  
Fluorescent Dye ◽  
Deep Imaging ◽  
Loading Amount

By changing the ratio of acrylic acid to styrene, the loading amount of fluorescent dye can be increased and the optical properties of the resulting bioimaging probe can be improved.

scholarly journals Effect of the enantiomeric structure of hydrophobic polymers on the encapsulation properties of a second near infrared (NIR-II) fluorescent dye for in vivo deep imaging

RSC Advances ◽  
2022 ◽  
Vol 12 (3) ◽  
pp. 1310-1318
Author(s):  
Kotoe Ichihashi ◽  
Masakazu Umezawa ◽  
Yuichi Ueya ◽  
Kyohei Okubo ◽  
Eiji Takamoto ◽  
...  
Keyword(s):  
Near Infrared ◽  
Fluorescent Dye ◽  
Hydrophobic Core ◽  
Hydrophobic Polymers ◽  
Deep Imaging

The enantiomeric structure of PLA affects its affinity for OTN-NIR fluorescent IR-1061 dye and its robustness when forming hydrophobic core micelles.

scholarly journals Multi-layered tissue head phantoms for noninvasive optical diagnostics

2015 ◽  
Vol 08 (03) ◽  
pp. 1541005 ◽  
Author(s):  
M. S. Wróbel ◽  
A. P. Popov ◽  
A. V. Bykov ◽  
M. Kinnunen ◽  
M. Jędrzejewska-Szczerska ◽  
...  
Keyword(s):  
Optical Properties ◽  
Near Infrared ◽  
Optical Measurement ◽  
Human Head ◽  
Medical Diagnostics ◽  
Optical Parameters ◽  
Measurement Systems ◽  
Tissue Phantoms ◽  
Optical And Mechanical Properties

Extensive research in the area of optical sensing for medical diagnostics requires development of tissue phantoms with optical properties similar to those of living human tissues. Development and improvement of in vivo optical measurement systems requires the use of stable tissue phantoms with known characteristics, which are mainly used for calibration of such systems and testing their performance over time. Optical and mechanical properties of phantoms depend on their purpose. Nevertheless, they must accurately simulate specific tissues they are supposed to mimic. Many tissues and organs including head possess a multi-layered structure, with specific optical properties of each layer. However, such a structure is not always addressed in the present-day phantoms. In this paper, we focus on the development of a plain-parallel multi-layered phantom with optical properties (reduced scattering coefficient [Formula: see text] and absorption coefficient μa) corresponding to the human head layers, such as skin, skull, and gray and white matter of the brain tissue. The phantom is intended for use in noninvasive diffuse near-infrared spectroscopy (NIRS) of human brain. Optical parameters of the fabricated phantoms are reconstructed using spectrophotometry and inverse adding-doubling calculation method. The results show that polyvinyl chloride-plastisol (PVCP) and zinc oxide ( ZnO ) nanoparticles are suitable materials for fabrication of tissue mimicking phantoms with controlled scattering properties. Good matching was found between optical properties of phantoms and the corresponding values found in the literature.

Influence of Blood Glucose Level on the Scattering Coefficient of the Skin in Near-Infrared Spectroscopy

2011 ◽  
Author(s):  
Sachiko Kessoku ◽  
Katsuhiko Maruo ◽  
Shinpei Okawa ◽  
Kazuto Masamoto ◽  
Yukio Yamada
Keyword(s):  
Optical Properties ◽  
Infrared Spectroscopy ◽  
Blood Glucose ◽  
Blood Glucose Level ◽  
Glucose Level ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Monitoring Methods ◽  
Absorbance Spectra

Various non-invasive glucose monitoring methods using near-infrared spectroscopy have been investigated although no method has been successful so far. Our previous study has proposed a new promising method utilizing numerically generated absorbance spectra instead of the experimentally acquired absorbance spectra. The method suggests that the correct estimation of the optical properties is very important for numerically generating the absorbance spectra. The purpose of this study is to measure the change in the optical properties of the skin with the change in the blood glucose level in vivo. By measuring the reflectances of light incident on the skin surface at two distances from the incident point, the optical properties of the skin can be estimated. The estimation is a kind of the inverse problem based on the simulation of light propagation in the skin. Phantom experiments have verified the method and in vivo experiments are to be performed.

Synthesis and optical properties of emission-tunable PbS/CdS core–shell quantum dots for in vivo fluorescence imaging in the second near-infrared window

RSC Advances ◽  
2014 ◽  
Vol 4 (77) ◽  
pp. 41164-41171 ◽  
Author(s):  
Yoshikazu Tsukasaki ◽  
Masatoshi Morimatsu ◽  
Goro Nishimura ◽  
Takao Sakata ◽  
Hidehiro Yasuda ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Optical Properties ◽  
Fluorescence Imaging ◽  
Near Infrared ◽  
Core Shell ◽  
Cds Quantum Dots ◽  
In Vivo Fluorescence ◽  
In Vivo Fluorescence Imaging ◽  
Infrared Window

This paper describes the synthesis and optical properties of PbS/CdS quantum dots for in vivo fluorescence imaging.

scholarly journals Optical investigation of bovine grey and white matters in visible and near-infrared ranges

2021 ◽  
Vol 27 (1) ◽  
pp. 99-107
Author(s):  
Ali Shahin ◽  
Wesam Bachir ◽  
Moustafa Sayem El-Daher
Keyword(s):  
Optical Properties ◽  
Absorption Coefficient ◽  
Wavelength Range ◽  
Grey Matter ◽  
Near Infrared ◽  
Biological Tissues ◽  
Integrating Sphere ◽  
Visible Range ◽  
Optical Investigation

Abstract Introduction: Due to enormous interests for laser in medicine and biology, optical properties characterization of different tissue have be affecting in development processes. In addition, the optical properties of biological tissues could be influenced by storage methods. Thus, optical properties of bovine white and grey tissues preserved by formalin have been characterized over a wide wavelength spectrum varied between 440 nm and 1000 nm. Materials and Methods: To that end, a single integrating sphere system was assembled for spectroscopic characterization and an inverse adding-doubling algorithm was used to retrieve optical coefficients, i.e. reduced scattering and absorption coefficients. Results: White matter has shown a strong scattering property in comparison to grey matter. On the other hand, the grey matter has absorbed light extensively. In comparison, the reduced scattering profile for both tissue types turned out to be consistent with prior works that characterized optical coefficients in vivo. On the contrary, absorption coefficient behavior has a different feature. Conclusion: Formalin could change the tissue’s optical properties because of the alteration of tissue’s structure and components. The absence of hemoglobin that seeps out due to the use of a formalin could reduce the absorption coefficient over the visible range. Both the water replacement by formalin could reduce the refractive index of a stored tissue and the absence of hemoglobin that scatters light over the presented wavelength range should diminish the reduced scattering coefficients over that wavelength range.

scholarly journals Development of a handheld diffuse optical breast cancer assessment probe

2016 ◽  
Vol 09 (02) ◽  
pp. 1650007 ◽  
Author(s):  
Majid Shokoufi ◽  
Farid Golnaraghi
Keyword(s):  
Breast Cancer ◽  
Optical Properties ◽  
Breast Tissue ◽  
Near Infrared ◽  
Human Subjects ◽  
Breast Cancer Diagnosis ◽  
Functional Brain Imaging ◽  
Wide Range ◽  
Concentration Changes

Diffuse Optical Spectroscopy (DOS) is a promising non-invasive and non-ionizing technique for breast anomaly detection. In this study, we have developed a new handheld DOS probe to measure optical properties of breast tissue. In the proposed probe, the breast tissue is illuminated with four near infrared (NIR) wavelengths light emitting diodes (LED), which are encapsulated in a package (eLEDs), and two PIN photodiodes measure the intensity of the scattered photons at two different locations. The proposed technique of using eLEDs is introduced, in order to have a multi-wavelength pointed-beam illumination source instead of using the laser-coupled fiber-optic technique, which increases the complexity, size, and cost of the probe. Despite the fact that the proposed technique miniaturizes the probe and reduces the complexity of the DOS, the study proves that it is accurate and reliable in measuring optical properties of the tissue. The measurements are performed at the rate of 10[Formula: see text]Hz which is suitable for dynamic measurement of biological activity, in-vivo. The multi-spectral evaluation algorithm is used to reconstruct four main absorber concentrations in the breast including oxy-hemoglobin (cHb), deoxy-hemoglobin (cHbO2), water (cH2O), fat (cFat), and average scattering coefficient of the medium, as well as concentration changes in Hb ([Formula: see text]cHb) and HbO2 ([Formula: see text]cHbO2). Although the probe is designed for breast cancer diagnosis, it can be used in a wide range of applications for both static and dynamic measurements such as functional brain imaging. A series of phantoms, comprised of Delrin[Formula: see text], Intralipid[Formula: see text], PierceTM and Black ink, are used to verify performance of the device. The probe will be tested on human subjects, in-vivo, in the next phase.

Transparent CuInS2 PMMA Nanocomposites Luminescent in the Visible and NIR Region

2014 ◽  
Vol 69 (2) ◽  
pp. 217-223 ◽  
Author(s):  
Krzysztof Guguła ◽  
Michael Bredol
Keyword(s):  
Optical Properties ◽  
Near Infrared ◽  
Deep Penetration ◽  
Ambient Conditions ◽  
White Leds ◽  
Functional Nanoparticles ◽  
Potential Applications ◽  
In Vivo Diagnostics ◽  
Transparent Polymers

Nanocomposites combining functional nanoparticles and transparent polymers allow for stabilization of filler properties over long periods of time while retaining transparency of the polymer matrix. Here we employ CuInS2/ZnS quantum dots (QDs), ternary visible- and NIR-emitting semiconductors as wavelength-tunable luminescent fillers. Luminescence in the near infrared (NIR) is of particular interest in medicine which allows deep penetration into human tissue enabling in vivo diagnostics and treatment, while visible emitters may serve as color converters in displays or lighting. To stabilize the optical properties of QDs and prevent agglomeration, polymethyl metacrylate (PMMA) was chosen as a matrix. These novel polymer nanocomposites (PNCs) show good optical properties and stability under ambient conditions, and can be easily deposited over large areas. High-quality QDs and hydrophobic functionalization with long-chain hydrocarbons are a prerequisite for embedding into a PMMA matrix. Transparent PNC films without visible scattering losses were obtained for 1 wt-% QD loading with respect to the polymer. Partial transparency is retained up to 10 wt-% QD loading and vanishes rapidly at higher loading. Luminescence properties increase up to 5 wt-% and then decrease rapidly due to QD agglomeration and reabsorption between adjacent particles. Potential applications include converter materials for medical applications, laser layers, displays and white LEDs.

scholarly journals Excessive Labeling Technique Provides a Highly Sensitive Fluorescent Probe for Real-time Monitoring of Biodegradation of Biopolymer Pharmaceuticals in vivo

Acta Naturae ◽  
2014 ◽  
Vol 6 (4) ◽  
pp. 54-59 ◽  
Author(s):  
S. S. Terekhov ◽  
I. V. Smirnov ◽  
O. G. Shamborant ◽  
M. A. Zenkova ◽  
E. L Chernolovskaya ◽  
...  
Keyword(s):  
Near Infrared ◽  
Living Organism ◽  
Fluorescent Dye ◽  
Pharmacokinetic Studies ◽  
Maximum Enhancement ◽  
Biodistribution Studies ◽  
Highly Sensitive ◽  
Pharmacokinetic Properties ◽  
Large Sector

Recombinant proteins represent a large sector of the biopharma market. Determination of the main elimination pathways raises the opportunities to significantly increase their half-lives in vivo. However, evaluation of biodegradation of pharmaceutical biopolymers performed in the course of pre-clinical studies is frequently complicated. Noninvasive pharmacokinetic and biodistribution studies in living organism are possible using proteins conjugated with near-infrared dyes. In the present study we designed a highly efficient probe based on fluorescent dye self-quenching for monitoring of in vivo biodegradation of recombinant human butyrylcholinesterase. The maximum enhancement of integral fluorescence in response to degradation of an intravenously administered enzyme was observed 6 h after injection. Importantly, excessive butyrylcholinesterase labeling with fluorescent dye results in significant changes in the pharmacokinetic properties of the obtained conjugate. This fact must be taken into consideration during future pharmacokinetic studies using in vivo bioimaging.

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