A Novel Biomimetic Nanoprobe as a Photoacoustic Contrast Agent

Specific detection of tumors is of pivotal importance to cancer prevention and therapy yet a big challenge. Photoacoustic imaging (PAI) as an emerging non-invasive modality has shown great potential in biomedical and clinical applications. The performance of PAI largely depends on the light-absorption coefficient of the imaged tissue and the PAI contrast agent being used, either endogenously or exogenously. The exogenous contrast agents developed so far have greatly helped to improve PAI, but still have some limitations, such as lack of targeting capacity and easy clearance by the host immune system. Herein, we fabricated a biomimetic nanoprobe with cell membrane coating as a novel PAI contrast agent, namely, MPD [membrane-coated poly(lactic-co-glycolic acid) (PLGA)/dye]. In brief, the organic dye 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindotricarbocyanine iodide (DiR) was encapsulated by the Food and Drug Administration–approved polymer, poly(lactic-co-glycolic acid) (PLGA), to form polymer nanoparticles by emulsification. The nanoparticles are further coated with the cancer cell membrane to form MPD. MPD has outstanding biocompatibility, tumor specificity, and in vivo stability. Thus, MPD is a versatile NIR-I theranostic nanoplatform for PAI-guided cancer diagnosis and therapy.

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Antimonene Nanoflakes as a Photoacoustic Imaging Contrast Agent for Tumor in vivo Imaging

Chinese Journal of Lasers ◽

10.3788/cjl202047.0207033 ◽

2020 ◽

Vol 47 (2) ◽

pp. 0207033

Author(s):

于静文 Yu Jingwen ◽

王秀翃 Wang Xiuhong ◽

冯金超 Feng Jinchao ◽

张娜 Zhang Na ◽

王璞 Wang Pu

Keyword(s):

Contrast Agent ◽

In Vivo Imaging ◽

Photoacoustic Imaging ◽

Imaging Contrast Agent

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Photoacoustic Imaging of Tattoo Inks: Phantom and Clinical Evaluation

Applied Sciences ◽

10.3390/app10031024 ◽

2020 ◽

Vol 10 (3) ◽

pp. 1024 ◽

Cited By ~ 1

Author(s):

Eftekhar Rajab Bolookat ◽

Laurie J. Rich ◽

Gyorgy Paragh ◽

Oscar R. Colegio ◽

Anurag K. Singh ◽

...

Keyword(s):

Photoacoustic Imaging ◽

Imaging Modality ◽

Preoperative Evaluation ◽

Healthy Human ◽

Non Invasive ◽

Diagnostic Applications ◽

Yellow Pigments ◽

Tattoo Inks

Photoacoustic imaging (PAI) is a novel hybrid imaging modality that provides excellent optical contrast with the spatial resolution of ultrasound in vivo. The method is widely being investigated in the clinical setting for diagnostic applications in dermatology. In this report, we illustrate the utility of PAI as a non-invasive tool for imaging tattoos. Ten different samples of commercially available tattoo inks were examined for their optoacoustic properties in vitro. In vivo PAI of an intradermal tattoo on the wrist was performed in a healthy human volunteer. Black/gray, green, violet, and blue colored pigments provided higher levels of PA signal compared to white, orange, red, and yellow pigments in vitro. PAI provided excellent contrast and enabled accurate delineation of the extent of the tattoo in the dermis. Our results reveal the photoacoustic properties of tattoo inks and demonstrate the potential clinical utility of PAI for intradermal imaging of tattoos. PAI may be useful as a clinical adjunct for objective preoperative evaluation of tattoos and potentially to guide/monitor laser-based tattoo removal procedures.

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Monitoring of Blood Flow by Drug Stimulation on Mouse Brain Using Non-Invasive Photoacoustic Imaging Technology

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.364-366.1123 ◽

2007 ◽

Vol 364-366 ◽

pp. 1123-1127

Author(s):

Shi Hua Yang ◽

Ye Qi Lao

Keyword(s):

Blood Flow ◽

Mouse Brain ◽

Light Absorption ◽

Brain Function ◽

Photoacoustic Imaging ◽

Non Invasive ◽

Mouse Cerebral Cortex ◽

Flow Changes ◽

The Brain

The highlight of photoacosutic imaging (PAI) is a method that combines ultrasonic resolution with high contrast due to light absorption. Photoacoustic signals carry the information of the light absorption distribution of biological tissue, which is often related to its character of structure, physiological and pathological changes because of different physiology conditions in response to different light absorption coefficients. A non-invasive PAI system was developed and successfully acquired in vivo images of mouse brain. Based on the intrinsic PA signals from the brain, the vascular network and the detailed structures of the mouse cerebral cortex were clearly visualized. The ability of PAI monitoring of cerebral hemodynamics was also demonstrated by mapping of the mouse superficial cortex with and without drug stimulation. The extracted PA signals intensity profiles obviously testified that the cerebral blood flow (CBF) in the mouse brain was changed under the stimulation of acetazolamide (ACZ). The experimental results suggest that PAI can provide non-invasive images of blood flow changes, and has the potential for brain function detection.

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Photoacoustic imaging for the prediction and assessment of response to radiotherapy in vivo

10.1101/329516 ◽

2018 ◽

Cited By ~ 1

Author(s):

Márcia Martinho Costa ◽

Anant Shah ◽

Ian Rivens ◽

Carol Box ◽

Tuathan O’Shea ◽

...

Keyword(s):

Treatment Response ◽

Group Treatment ◽

Photoacoustic Imaging ◽

Subsequent Treatment ◽

Blood Oxygen Saturation ◽

Non Invasive ◽

Pre Treatment ◽

Haemoglobin Content ◽

Better Than

AbstractRadiotherapy is commonly used for cancer therapy, although its efficacy is reduced in hypoxic regions of tumours. Photoacoustic imaging (PAI) is an emergent, non-invasive imaging technique that allows the measurement of blood oxygen saturation (sO2) which inversely correlates with hypoxia in tissue. The potential use of PAI as a prognostic tool for radiotherapy outcome was investigated in a head and neck cancer model in vivo. PAI was performed before delivering a single fraction (10, 20 or 30 Gy) treatment. The results show that tumours with pre-treatment higher blood sO2 responded better than those with lower levels in the 10 and 20 Gy groups. For the 30 Gy group, treatment response was independent of blood sO2. The haemoglobin content of the tumours was not correlated with their response to any of the radiation doses studied. Changes in sO2, monitored at 24 h and 96 h following 10 and 20 Gy doses, showed that tumours that were subsequently unresponsive to treatment had an increase in blood sO2 at both time points compared to those which subsequently regressed after radiotherapy. The results suggest that sO2 values measured by photoacoustic imaging can be used before, and shortly after, irradiation to predict subsequent treatment response.

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Photoacoustic Properties of Polypyrrole Nanoparticles

Nanomaterials ◽

10.3390/nano11092457 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2457

Author(s):

Peter Keša ◽

Monika Paúrová ◽

Michal Babič ◽

Tomáš Heizer ◽

Petr Matouš ◽

...

Keyword(s):

Contrast Agent ◽

Photoacoustic Imaging ◽

Particle Surface ◽

Photoacoustic Signal ◽

Ammonium Persulphate ◽

Coated Nanoparticles ◽

Polypyrrole Nanoparticles ◽

Signal Dependence

Photoacoustic imaging, an emerging modality, provides supplemental information to ultrasound imaging. We investigated the properties of polypyrrole nanoparticles, which considerably enhance contrast in photoacoustic images, in relation to the synthesis procedure and to their size. We prepared polypyrrole nanoparticles by water-based redox precipitation polymerization in the presence of ammonium persulphate (ratio nPy:nOxi 1:0.5, 1:1, 1:2, 1:3, 1:5) or iron(III) chloride (nPy:nOxi 1:2.3) acting as an oxidant. To stabilize growing nanoparticles, non-ionic polyvinylpyrrolidone was used. The nanoparticles were characterized and tested as a photoacoustic contrast agent in vitro on an imaging platform combining ultrasound and photoacoustic imaging. High photoacoustic signals were obtained with lower ratios of the oxidant (nPy:nAPS ≥ 1:2), which corresponded to higher number of conjugated bonds in the polymer. The increasing portion of oxidized structures probably shifted the absorption spectra towards shorter wavelengths. A strong photoacoustic signal dependence on the nanoparticle size was revealed; the signal linearly increased with particle surface. Coated nanoparticles were also tested in vivo on a mouse model. To conclude, polypyrrole nanoparticles represent a promising contrast agent for photoacoustic imaging. Variations in the preparation result in varying photoacoustic properties related to their structure and allow to optimize the nanoparticles for in vivo imaging.

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Photoacoustic molecular imaging using combined acupuncture and gold nanorods as a composite contrast agent

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545819410049 ◽

2019 ◽

Vol 12 (03) ◽

pp. 1941004

Author(s):

Dan Wu ◽

Xinxin Zhang ◽

Jian Rong ◽

Huabei Jiang

Keyword(s):

Contrast Agent ◽

Contrast Enhancement ◽

Mouse Brain ◽

Gold Nanorods ◽

Near Infrared ◽

Photoacoustic Imaging ◽

Local Concentration ◽

Quantitative Results ◽

Zusanli Acupoint

In this study, we developed a novel photoacoustic imaging technique based on poly (ethyleneglycol)-coated (PEGylated) gold nanorods (PEG-GNRs) (as the contrast agent) combined with traditional Chinese medicine (TCM) acupuncture (as the auxiliary method) for quantitatively monitoring contrast enhancement in the vasculature of a mouse brain in vivo. This study takes advantage of the strong near-infrared absorption (peak at [Formula: see text][Formula: see text]nm) of GNRs and the ability to adjust the hemodynamics of acupuncture. Experimental results show that photoacoustic tomography (PAT) successfully reveals the optical absorption variation of the vasculature of the mouse brain in response to intravenous administration of GNRs and acupuncture at the Zusanli acupoint (ST36) both individually and combined. The quantitative measurement of contrast enhancement indicates that the composite contrast agents (integration of acupuncture and GNRs) would greatly enhance the photoacoustic imaging contrast. The quantitative results also have the potential to estimate the local concentration of GNRs and even the real-time effects of acupuncture.

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Non-invasive and low-artifact in vivo brain imaging by using a scanning acoustic-photoacoustic dual mode microscopy

Chinese Physics B ◽

10.1088/1674-1056/ac4a6f ◽

2022 ◽

Author(s):

Wentian Chen ◽

Chao Tao ◽

Zizhong Hu ◽

Songtao Yuan ◽

Qinghuai Liu ◽

...

Keyword(s):

Brain Imaging ◽

Photoacoustic Imaging ◽

Acoustic Microscopy ◽

Acoustic Properties ◽

Potential Candidate ◽

Photoacoustic Microscopy ◽

Phantom Experiment ◽

Non Invasive ◽

Imaging Performance

Abstract Photoacoustic imaging is a potential candidate for in-vivo brain imaging, whereas, its imaging performance could be degraded by inhomogeneous multi-layered media, consisted of scalp and skull. In this work, we propose a low-artifact photoacoustic microscopy (LAPAM) scheme, which combines conventional acoustic-resolution photoacoustic microscopy with scanning acoustic microscopy to suppress the reflection artifacts induced by multi-layers. Based on similar propagation characteristics of photoacoustic signals and ultrasonic echoes, the ultrasonic echoes can be employed as the filters to suppress the reflection artifacts to obtain low-artifact photoacoustic images. Phantom experiment is used to validate the effectiveness of this method. Furthermore, LAPAM is applied for in-vivo imaging mouse brain without removing the scalp and the skull. Experimental results show that the proposed method successfully achieves the low-artifact brain image, which demonstrates the practical applicability of LAPAM. This work might improve the photoacoustic imaging quality in many biomedical applications, which involve tissue with complex acoustic properties, such as brain imaging through scalp and skull.

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