Broadband near infrared (NIR) emission materials are of interest for various applications including non-destructive biomedical imaging. In this work, ytterbium ions (Yb 3+ ) were successfully doped into Cs 2 AgInCl 6 :Cr 3+ (CAIC:Cr 3+ ) double perovskite single crystals (DPSCs) by a facile hydrothermal method. Under 365 nm excitation, the co-doped CAIC:Cr 3+ ,Yb 3+ DPSCs showed broad NIR emission ranging from 800 to 1400 nm, which spanned the NIR-I (700–900 nm) and NIR-II (1000–1700 nm) bio-windows, with an emission band at 1000 nm and a full-width at half maximum (FWHM) of 188 nm. It is found that Yb 3+ ion doping could effectively improve the photoluminescence (PL) performance of CAIC:Cr 3+ DPSCs. Compared to the photoluminescence quantum yield (PLQY) of 22.5% for the single doped CAIC:Cr 3+ , the co-doped CAIC:Cr 3+ ,Yb 3+ DPSCs show a higher PLQY of ∼45%, which is attributed to the synergistic effect of reduced non-radiative recombination due to defect passivation and increase in crystallinity, and energy transfer (ET) of self-trapped excitons (STEs) to Cr 3+ . As a demonstration of applications, NIR pc-LEDs were fabricated by combining the as-synthesized NIR-emitting phosphor CAIC:Cr 3+ ,Yb 3+ with InGaN UV chips ( λ em = 365 nm) and used to image veins in a palm and for night vision using a NIR camera. The results suggest that the synthesized CAIC:Cr 3+ ,Yb 3+ DPSCs have great potential in biological applications.
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A proof of concept ‘phase zero’ study of neurodevelopment using brain organoid models with Vis/near-infrared spectroscopy and electrophysiology
Abstract Homeostatic control of neuronal excitability by modulation of synaptic inhibition (I) and excitation (E) of the principal neurons is important during brain maturation. The fundamental features of in-utero brain development, including local synaptic E–I ratio and bioenergetics, can be modeled by cerebral organoids (CO) that have exhibited highly regular nested oscillatory network events. Therefore, we evaluated a 'Phase Zero' clinical study platform combining broadband Vis/near-infrared(NIR) spectroscopy and electrophysiology with studying E–I ratio based on the spectral exponent of local field potentials and bioenergetics based on the activity of mitochondrial Cytochrome-C Oxidase (CCO). We found a significant effect of the age of the healthy controls iPSC CO from 23 days to 3 months on the CCO activity (chi-square (2, N = 10) = 20, p = 4.5400e−05), and spectral exponent between 30–50 Hz (chi-square (2, N = 16) = 13.88, p = 0.001). Also, a significant effect of drugs, choline (CHO), idebenone (IDB), R-alpha-lipoic acid plus acetyl- l -carnitine (LCLA), was found on the CCO activity (chi-square (3, N = 10) = 25.44, p = 1.2492e−05), spectral exponent between 1 and 20 Hz (chi-square (3, N = 16) = 43.5, p = 1.9273e−09) and 30–50 Hz (chi-square (3, N = 16) = 23.47, p = 3.2148e−05) in 34 days old CO from schizophrenia (SCZ) patients iPSC. We present the feasibility of a multimodal approach, combining electrophysiology and broadband Vis–NIR spectroscopy, to monitor neurodevelopment in brain organoid models that can complement traditional drug design approaches to test clinically meaningful hypotheses.
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- Award ID(s):
- 1706050
- PAR ID:
- 10280069
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 10
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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