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Brain photobiomodulation (PBM) describes the use of visible to near-infrared light for modulation or stimulation of the central nervous system in both healthy individuals and diseased conditions. Although the transcranial approach to delivering light to the head is the most common technique to stimulate the brain, delivery of light to deeper structures in the brain is still a challenge. The science of nanoparticle engineering in combination with biophotonic excitation could provide a way to overcome this problem. Upconversion is an anti-Stokes process that is capable of transforming low energy photons that penetrate tissue well to higher energy photons with a greater biological effect, but poor tissue penetration. Wavelengths in the third optical window are optimal for light penetration into brain tissue, followed by windows II, IV, and I. The combination of trivalent lanthanide ions within a crystalline host provides a nanostructure that exhibits the upconversion phenomenon. Upconverting nanoparticles (UCNPs) have been successfully used in various medical fields. Their ability to cross the brain-blood barrier and their low toxicity make them a good candidate for application in brain disorders. It is possible that delivery of UCNPs to the brainstem or deeper parts of the cerebral tissue, followed by irradiation using light wavelengths with good tissue penetration properties, could allow more efficient PBM of the brain.
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http://dx.doi.org/10.1089/photob.2019.4659 | DOI Listing |
Anal Chim Acta
November 2025
Institute of Nano Science and Technology, Knowledge City, Sahibzada Ajit Singh Nagar, Sector- 81, Punjab, 140306, India. Electronic address:
Background: Iron (Fe) is an essential micronutrient for plant growth, but the conventional DTPA soil analysis method for detecting available iron has notable limitations, requiring advanced instruments and lengthy preparation time. Developing a more affordable, user-friendly, and efficient method for iron detection in soil could greatly improve crop nutrition management. Here, a facile nanoscopic method was developed to quantify available Fe ions in the soil by forming a luminescence quenching complex in chelation with bathophenanthroline disulphonic acid disodium salt (Fe/BPDS complex).
View Article and Find Full Text PDFACS Appl Mater Interfaces
September 2025
Department of Mining and Materials Engineering, McGill University, 3610 Rue University, Montreal, Quebec, Canada H3A 0C5.
As the first-line chemotherapeutic for glioblastoma multiforme (GBM), Temozolomide (TMZ) suffers from rapid degradation in physiological fluid, making it difficult to deliver sufficient doses of active TMZ to GBM tumors without inducing severe side effects. By protecting TMZ and then controlling its release using an external stimulus, we can prevent its premature degradation, thereby increasing its active concentration at the tumor site. Here, we present a near-infrared (NIR) controlled system in which TMZ is protected within a polymer before its on-demand release.
View Article and Find Full Text PDFChemosphere
August 2025
Department of Rare Earths, Faculty of Chemistry, Adam Mickiewicz University, Poznań, Uniwersytetu Poznańskiego 8, 61-614, Poznań, Poland. Electronic address:
Manufacturers use polyethylene terephthalate (PET) to create many everyday objects, which break down into nanoparticles when released into the environment. This fact raises questions about the effects of nanometric PET on living organisms, including bacteria. However, studies on nanoPET are rare and challenging, even if only because its detection and visualisation are difficult.
View Article and Find Full Text PDFACS Omega
July 2025
Division Biophotonics, Federal Institute for Materials Research and Testing (BAM), Richard-Willstaetter-Str. 11, D-12489 Berlin, Germany.
Chemically stable, lanthanide-based photon upconversion micro- and nanoparticles (UCNPs) with their characteristic multicolor emission bands in the ultraviolet (UV), visible (vis), near-infrared (NIR), and short-wave infrared (SWIR) are promising optical reporters and barcoding tags. To assess the applicability of UCNPs for the monitoring of early stage cement hydration processes and as authentication tags for cementitious materials, we screened the evolution of the luminescence of self-made core-only NaYF:Yb,Er UCNPs and commercial μm-sized YOS:Yb,Er particles during the first stages of cement hydration, which largely determines the future properties of the hardened material. Parameters explored from the UCNP side included particle size, morphology, surface chemistry or coating, luminescence properties, and concentration in different cement mixtures.
View Article and Find Full Text PDFNanoscale
August 2025
Department of Optics, Complutense University of Madrid, E-28037 Madrid, Spain.
Accurate and reliable quantification of Förster Resonance Energy Transfer (FRET) is essential for the development of sensitive upconverting nanoparticle (UCNP)-based biosensors. While lifetime-based FRET measurements are generally considered robust, excitation conditions can significantly bias observed efficiencies. Here, we investigate how excitation pulse width and power influence lifetime-derived FRET efficiency in core-shell β-NaYF:Yb@NaYF:Yb,Er UCNPs functionalized with Cy3 dyes.
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