Fluorescently Labeled Cellulose Nanofibers for Environmental Health and Safety Studies

An optimal methodology for locating and tracking cellulose nanofibers (CNFs) in vitro and in vivo is crucial to evaluate the environmental health and safety properties of these nanomaterials. Here, we report the use of a new boron-dipyrromethene (BODIPY) reactive fluorescent probe, meso-DichlorotriazineEthyl BODIPY (mDTEB), tailor-made for labeling CNFs used in simulated or in vivo ingestion exposure studies. Time-correlated single photon counting (TCSPC) fluorescence lifetime imaging microscopy (FLIM) was used to confirm covalent attachment and purity of mDTEB-labeled CNFs. The photoluminescence properties of mDTEB-labeled CNFs, characterized using fluorescence spectroscopy, include excellent stability over a wide pH range (pH2 to pH10) and high quantum yield, which provides detection at low (μM) concentrations. FLIM analysis also showed that lignin-like impurities present on the CNF reduce the fluorescence of the mDTEB-labeled CNF, via quenching. Therefore, the chemical composition and the methods of CNF production affect subsequent studies. An in vitro triculture, small intestinal, epithelial model was used to assess the toxicity of ingested mDTEB-labeled CNFs. Zebrafish (Danio rerio) were used to assess in vivo environmental toxicity studies. No cytotoxicity was observed for CNFs, or mDTEB-labeled CNFs, either in the triculture cells or in the zebrafish embryos.

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Physical, chemical, and in vitro toxicological characterization of nanoparticles in chemical mechanical planarization suspensions used in the semiconductor industry: towards environmental health and safety assessments

Environmental Science Nano ◽

10.1039/c5en00046g ◽

2015 ◽

Vol 2 (3) ◽

pp. 227-244 ◽

Cited By ~ 27

Author(s):

David Speed ◽

Paul Westerhoff ◽

Reyes Sierra-Alvarez ◽

Rockford Draper ◽

Paul Pantano ◽

...

Keyword(s):

Environmental Health ◽

Semiconductor Industry ◽

Chemical Mechanical Planarization ◽

Health And Safety ◽

Engineered Nanoparticles ◽

Environmental Health And Safety ◽

Physical Chemical ◽

Safety Assessments

This tutorial review focuses on aqueous slurries of dispersed engineered nanoparticles (ENPs) used in chemical mechanical planarization (CMP) for polishing wafers during manufacturing of semiconductors.

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Approach to Environmental, Health and Safety Issues of Nanotechnology in Japan

Journal of Disaster Research ◽

10.20965/jdr.2011.p0506 ◽

2011 ◽

Vol 6 (5) ◽

pp. 506-513 ◽

Cited By ~ 1

Author(s):

Masahiro Takemura ◽

◽

Go Yoshizawa ◽

Tatsujiro Suzuki ◽

◽

...

Keyword(s):

Environmental Health ◽

Health And Safety ◽

Working Party ◽

Scientific Data ◽

Japanese Government ◽

The Body ◽

Environmental Health And Safety ◽

Safety Issues ◽

Health And Safety Issues

In environmental, health, and safety issues of nanotechnology (nanoEHS), at present, risk assessment and management of nanomaterials to protect workers, consumers, and the environment is the most urgent. Workers have the highest possibility of being exposed to nanomaterials in workplaces, where nanomaterials may be inhaled or enter the body through dermal exposure. Several kinds of in-vivo tests have been done to assess the hazards of nanomaterials, mainly in terms of immunity response and carcinogenicity. Most advanced countries agree that it is important to manage the risks of nanomaterials with using the existing framework for chemical substances as much as possible to minimize risks, product of hazard and exposure. Research papers on the hazards of nanomaterials have been increasing, but there have been comparatively little scientific data related to exposuremeasurement. The Japanese government and national research institutes have been proactively committed to this issue since 2004. In addition to supporting several domestic projects, the Japanese government proactively joined international bodies such as the OECD Working Party on Manufactured Nanomaterials and ISO TC-229. Still, much more scientific data in appropriate studies and more discussion by appropriate participants are needed although funding is limited. To improve the situation, proposals have included (1) promoting basic research on nanoEHS, (2) increasing opportunities for scientific discussion on nanoEHS, (3) working continuously to construct and maintain databases on nanoEHS, (4) promoting the involvement of multistakeholders in nanoEHS, and (5) having ministries working cooperatively and efficiently on nanoEHS.

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In vitro and in vivo NIR Fluorescence Lifetime Imaging with a time-gated SPAD camera

10.1101/2021.12.26.474189 ◽

2021 ◽

Author(s):

Jason T. Smith ◽

Alena Rudkouskaya ◽

Shan Gao ◽

Juhi M. Gupta ◽

Arin Ulku ◽

...

Keyword(s):

Fluorescence Lifetime ◽

Near Infrared ◽

Single Photon ◽

In Vivo Studies ◽

Fluorescence Lifetime Imaging ◽

Iccd Camera ◽

Lifetime Imaging ◽

Nir Fluorescence

Near-infrared (NIR) fluorescence lifetime imaging (FLI) provides a unique contrast mechanism to monitor biological parameters and molecular events in vivo. Single-photon avalanche photodiode (SPAD) cameras have been recently demonstrated in FLI microscopy (FLIM) applications, but their suitability for in vivo macroscopic FLI (MFLI) in deep tissues remains to be demonstrated. Herein, we report in vivo NIR MFLI measurement with SwissSPAD2, a large time-gated SPAD camera. We first benchmark its performance in well-controlled in vitro experiments, ranging from monitoring environmental effects on fluorescence lifetime, to quantifying Förster Resonant Energy Transfer (FRET) between dyes. Next, we use it for in vivo studies of target-drug engagement in live and intact tumor xenografts using FRET. Information obtained with SwissSPAD2 was successfully compared to that obtained with a gated-ICCD camera, using two different approaches. Our results demonstrate that SPAD cameras offer a powerful technology for in vivo preclinical applications in the NIR window.

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