scholarly journals A microrobotic system guided by photoacoustic computed tomography for targeted navigation in intestines in vivo

2019 ◽  
Vol 4 (32) ◽  
pp. eaax0613 ◽  
Author(s):  
Zhiguang Wu ◽  
Lei Li ◽  
Yiran Yang ◽  
Peng Hu ◽  
Yang Li ◽  
...  

Recently, tremendous progress in synthetic micro/nanomotors in diverse environment has been made for potential biomedical applications. However, existing micro/nanomotor platforms are inefficient for deep tissue imaging and motion control in vivo. Here, we present a photoacoustic computed tomography (PACT)–guided investigation of micromotors in intestines in vivo. The micromotors enveloped in microcapsules are stable in the stomach and exhibit efficient propulsion in various biofluids once released. The migration of micromotor capsules toward the targeted regions in intestines has been visualized by PACT in real time in vivo. Near-infrared light irradiation induces disintegration of the capsules to release the cargo-loaded micromotors. The intensive propulsion of the micromotors effectively prolongs the retention in intestines. The integration of the newly developed microrobotic system and PACT enables deep imaging and precise control of the micromotors in vivo and promises practical biomedical applications, such as drug delivery.

2018 ◽  
Author(s):  
Fabiane Sônego ◽  
Sophie Bouccara ◽  
Thomas Pons ◽  
Nicolas Lequeux ◽  
Anne Danckaert ◽  
...  

AbstractEarly detection of tumours is today a major challenge and requires sensitive imaging methodologies coupled with new efficient probes. Bioluminescence imaging has been widely used in the field of oncology and several cancer cell lines have been genetically modified to provide bioluminescence signals. However, photons that are emitted by the majority of commonly used luciferases are usually in the blue part of the visible spectrum, where tissue absorption is still very high, making deep tissue imaging non-optimal and calling for optimised optical imaging methodologies. We have previously shown that red-shifting of bioluminescence signal by Fluorescence Unbound Excitation from Luminescence (FUEL) is a mean to increase bioluminescence signal sensitivity detection in vivo. Here, we applied FUEL to tumour detection in two different subcutaneous tumour models: the auto-luminescent human embryonic kidney (HEK293) cell line and the murine B16-F10 melanoma cell line previously transfected with the plasmid Luc2. Tumour size and bioluminescence were measured over time and tumour vascularization characterized. We then locally injected near infrared emitting Quantum Dots (NIR QDs)in the tumour site and observed a red-shifting of bioluminescence signal by (FUEL) indicating that FUEL could be used to allow deeper tumour detection.


RSC Advances ◽  
2017 ◽  
Vol 7 (24) ◽  
pp. 14805-14808 ◽  
Author(s):  
Seulgi Han ◽  
Songeun Beack ◽  
Sanghwa Jeong ◽  
Byung Woo Hwang ◽  
Myeong Hwan Shin ◽  
...  

We successfully developed an NIR light-triggered in vivo on–off tattoo system using hyaluronate modified upconversion nanoparticles for various biomedical applications.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1535
Author(s):  
Masfer Alkahtani ◽  
Anfal Alfahd ◽  
Najla Alsofyani ◽  
Anas A. Almuqhim ◽  
Hussam Qassem ◽  
...  

In this work, we report a simple method of silica coating of upconversion nanoparticles (UCNPs) to obtain well-crystalline particles that remain small and not agglomerated after high-temperature post-annealing, and produce bright visible emission when pumped with near-infrared light. This enables many interesting biological applications, including high-contrast and deep tissue imaging, quantum sensing and super-resolution microscopy. These VO4-based UNCPs are an attractive alternative to fluoride-based crystals for water-based biosensing applications.


Nanoscale ◽  
2017 ◽  
Vol 9 (25) ◽  
pp. 8631-8638 ◽  
Author(s):  
Jin-Lei Li ◽  
Jun-Peng Shi ◽  
Cheng-Cheng Wang ◽  
Peng-Hui Li ◽  
Zhen-Feng Yu ◽  
...  

Schematic illustration of the synthesis, functionalization and repeated in vivo simulated deep tissue imaging of ZSO NPLNPs.


2020 ◽  
Vol 8 (35) ◽  
pp. 7856-7879
Author(s):  
Fan Yang ◽  
Qingzhe Zhang ◽  
Shengyun Huang ◽  
Dongling Ma

Near infrared (NIR)-excitable and NIR-emitting probes have fuelled advances in biomedical applications owing to their power in enabling deep tissue imaging, offering high image contrast and reducing phototoxicity.


2020 ◽  
Author(s):  
James Joseph ◽  
Kevin N. Baumann ◽  
Alejandro Postigo ◽  
Laura Bollepalli ◽  
Sarah E. Bohndiek ◽  
...  

AbstractOptoacoustic tomography (OT) enables non-invasive deep tissue imaging of optical contrast at high spatio-temporal resolution. The applications of OT in cancer imaging often rely on the use of molecular imaging contrast agents based on near infrared dyes to enhance contrast at the tumor site. While these agents afford excellent biocompatibility and minimal toxicity, they present limited optoacoustic signal generation capability and rapid renal clearance, which can impede their tumor imaging efficacy. In this work, a synthetic strategy to overcome these limitations utilizing biodegradable DNA-based nanocarrier (DNA-NC) platforms is introduced. DNA-NCs enable the incorporation of near infrared dyes (in this case, IRDye 800CW) at precise positions to enable fluorescence quenching and maximize optoacoustic signal generation. Furthermore, these DNA-NCs show a prolonged blood circulation compared to the native fluorophores, facilitating tumor accumulation by the Enhanced Permeability and Retention (EPR) effect. In vivo imaging of tumor xenografts in mice following intravenous administration of DNA-NCs revealed enhanced OT signals at 24h when compared to free fluorophores, indicating promise for this method to enhance the optoacoustic signal generation capability and tumor uptake of clinically relevant near infrared dyes.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Chul-Kyu Park ◽  
Hoonsung Cho

Fluorescence imaging using fluorescent probes has demonstrated long-term stability and brightness suitable forin vivodeep-tissue imaging, but it also allows intense background fluorescence associated with food in the near-infrared (IR) range. We investigated effects of changing rodent diet on food autofluorescence, in the presence of quantum dots-conjugated magnetic nanospheres (QD-MNSs). Replacement of a regular rodent diet with a purified diet has great improvement in removing autofluorescence in the near-infrared range ideal forin vivofluorescence imaging. By feeding a purified diet for eliminating ingredients impairing desirable fluorescence signals in the near-IR range, food autofluorescence was clearly eliminated and fluorescence probes, QD-MNSs, introduced by i.v. injection were effectively traced in a mouse by a distinctive signal-to-noise ratio.


2008 ◽  
Vol 8 (3) ◽  
pp. 1155-1159 ◽  
Author(s):  
Jun Zhang ◽  
Junfeng Su ◽  
Li Liu ◽  
Yalou Huang ◽  
Ralph P. Mason

Non-invasive fluorescent imaging of preclinical animal models in vivo is a rapidly developing field with new emerging technologies and techniques. Quantum dot (QD) fluorescent probes with longer emission wavelengths in red and near infrared (NIR) emission ranges are more amenable to deep-tissue imaging, because both scattering and autofluorescence are reduced as wavelengths are increased. We have designed and synthesized red CdTe and NIR CdHgTe QDs for fluorescent imaging. We demonstrated fluorescent imaging by using CdTe and CdHgTe QDs as fluorescent probes both in vitro and in vivo. Both CdTe and CdHgTe QDs provided sensitive detection over background autofluorescence in tissue biopsies and live mice, making them attractive probes for in vivo imaging extending into deep tissues or whole animals. The studies suggest a basis of using QD-antibody conjugates to detect membrane antigens.


2020 ◽  
Vol 48 (6) ◽  
pp. 2657-2667
Author(s):  
Felipe Montecinos-Franjola ◽  
John Y. Lin ◽  
Erik A. Rodriguez

Noninvasive fluorescent imaging requires far-red and near-infrared fluorescent proteins for deeper imaging. Near-infrared light penetrates biological tissue with blood vessels due to low absorbance, scattering, and reflection of light and has a greater signal-to-noise due to less autofluorescence. Far-red and near-infrared fluorescent proteins absorb light >600 nm to expand the color palette for imaging multiple biosensors and noninvasive in vivo imaging. The ideal fluorescent proteins are bright, photobleach minimally, express well in the desired cells, do not oligomerize, and generate or incorporate exogenous fluorophores efficiently. Coral-derived red fluorescent proteins require oxygen for fluorophore formation and release two hydrogen peroxide molecules. New fluorescent proteins based on phytochrome and phycobiliproteins use biliverdin IXα as fluorophores, do not require oxygen for maturation to image anaerobic organisms and tumor core, and do not generate hydrogen peroxide. The small Ultra-Red Fluorescent Protein (smURFP) was evolved from a cyanobacterial phycobiliprotein to covalently attach biliverdin as an exogenous fluorophore. The small Ultra-Red Fluorescent Protein is biophysically as bright as the enhanced green fluorescent protein, is exceptionally photostable, used for biosensor development, and visible in living mice. Novel applications of smURFP include in vitro protein diagnostics with attomolar (10−18 M) sensitivity, encapsulation in viral particles, and fluorescent protein nanoparticles. However, the availability of biliverdin limits the fluorescence of biliverdin-attaching fluorescent proteins; hence, extra biliverdin is needed to enhance brightness. New methods for improved biliverdin bioavailability are necessary to develop improved bright far-red and near-infrared fluorescent proteins for noninvasive imaging in vivo.


2019 ◽  
Author(s):  
Arundhati Deshmukh ◽  
Danielle Koppel ◽  
Chern Chuang ◽  
Danielle Cadena ◽  
Jianshu Cao ◽  
...  

Technologies which utilize near-infrared (700 – 1000 nm) and short-wave infrared (1000 – 2000 nm) electromagnetic radiation have applications in deep-tissue imaging, telecommunications and satellite telemetry due to low scattering and decreased background signal in this spectral region. However, there are few molecular species, which absorb efficiently beyond 1000 nm. Transition dipole moment coupling (e.g. J-aggregation) allows for redshifted excitonic states and provides a pathway to highly absorptive electronic states in the infrared. We present aggregates of two cyanine dyes whose absorption peaks redshift dramatically upon aggregation in water from ~ 800 nm to 1000 nm and 1050 nm with sheet-like morphologies and high molar absorptivities (e ~ 10<sup>5 </sup>M<sup>-1</sup>cm<sup>-1</sup>). To describe this phenomenology, we extend Kasha’s model for J- and H-aggregation to describe the excitonic states of <i> 2-dimensional aggregates</i> whose slip is controlled by steric hindrance in the assembled structure. A consequence of the increased dimensionality is the phenomenon of an <i>intermediate </i>“I-aggregate”, one which redshifts yet displays spectral signatures of band-edge dark states akin to an H-aggregate. We distinguish between H-, I- and J-aggregates by showing the relative position of the bright (absorptive) state within the density of states using temperature dependent spectroscopy. Our results can be used to better design chromophores with predictable and tunable aggregation with new photophysical properties.


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