Upconverted excitation energy lock-in for deep-ultraviolet enhancement

Abstract Photon upconversion of near-infrared (NIR) irradiation into deep-ultraviolet (UV) emission offers many exciting opportunities for drug release in deep tissues, photodynamic therapy, solid-state lasing, energy storage, and photocatalysis. However, NIR-to-deep-UV upconversion remains a daunting challenge due to low quantum efficiency. Here, we report an unusual six-photon upconversion process in Gd3+/Tm3+-codoped nanoparticles comprising a heterogeneous, core-multishell nanostructure. This multishell design efficiently suppresses energy consumption induced by interior energy traps, maximizes cascade sensitizations of the NIR excitation, and promotes upconverted deep-UV emission from high-lying excited states. We released the intense six-photon-upconverted UV emissions at 253 nm under 808-nm excitation. This work provides new insight into mechanistic understanding of the upconversion process within the heterogeneous architecture, while offering exciting opportunities for developing nanoscale deep-UV emitters that can be remotely controlled in deep tissues upon NIR illumination.

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Six-photon upconverted excitation energy lock-in for ultraviolet-C enhancement

Nature Communications ◽

10.1038/s41467-021-24664-x ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Qianqian Su ◽

Han-Lin Wei ◽

Yachong Liu ◽

Chaohao Chen ◽

Ming Guan ◽

...

Keyword(s):

Photodynamic Therapy ◽

Energy Consumption ◽

Excited States ◽

Near Infrared ◽

Heterogeneous Architecture ◽

Ultraviolet C ◽

Daunting Challenge ◽

Lock In ◽

Insight Into ◽

Upconversion Process

AbstractPhoton upconversion of near-infrared (NIR) irradiation into ultraviolet-C (UVC) emission offers many exciting opportunities for drug release in deep tissues, photodynamic therapy, solid-state lasing, energy storage, and photocatalysis. However, NIR-to-UVC upconversion remains a daunting challenge due to low quantum efficiency. Here, we report an unusual six-photon upconversion process in Gd3+/Tm3+-codoped nanoparticles following a heterogeneous core-multishell architecture. This design efficiently suppresses energy consumption induced by interior energy traps, maximizes cascade sensitizations of the NIR excitation, and promotes upconverted UVC emission from high-lying excited states. We realized the intense six-photon-upconverted UV emissions at 253 nm under 808 nm excitation. This work provides insight into mechanistic understanding of the upconversion process within the heterogeneous architecture, while offering exciting opportunities for developing nanoscale UVC emitters that can be remotely controlled through deep tissues upon NIR illumination.

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Enhancing Deep-UV Emission at 234 nm by Introducing Truncated Pyramid AlN/GaN Nanostructure with Fine-tuned Multiple Facets

Nanoscale ◽

10.1039/d1nr06188g ◽

2021 ◽

Author(s):

Shiqiang Lu ◽

Xinjun Jiang ◽

Yaozeng Wang ◽

Kai Huang ◽

Na Gao ◽

...

Keyword(s):

Wavelength Range ◽

External Quantum Efficiency ◽

Light Emitting Diode ◽

Light Emitting ◽

Al Content ◽

Uv Emission ◽

Deep Ultraviolet ◽

Deep Uv ◽

High Al Content ◽

Truncated Pyramid

The external quantum efficiency of a high-Al content (>0.6) AlGaN deep-ultraviolet (DUV) light-emitting diode is typically below 1% in the sub-250 nm wavelength range. One of the main reasons for...

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Deep-UV emission at 260 nm from MBE-grown AlGaN/AlN quantum-well structures

Journal of Crystal Growth ◽

10.1016/j.jcrysgro.2019.02.037 ◽

2019 ◽

Vol 512 ◽

pp. 213-218 ◽

Cited By ~ 2

Author(s):

Wenxian Yang ◽

Yukun Zhao ◽

Yuanyuan Wu ◽

Xuefei Li ◽

Zhiwei Xing ◽

...

Keyword(s):

Quantum Well ◽

Quantum Well Structures ◽

Uv Emission ◽

Deep Uv

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Assessment of chicken breast shelf life based on bench-top and portable NIR spectroscopy tools coupled with chemometrics

Food Quality and Safety ◽

10.1093/fqsafe/fyaa032 ◽

2020 ◽

Author(s):

Ilaria Lanza ◽

Daniele Conficoni ◽

Stefania Balzan ◽

Marco Cullere ◽

Luca Fasolato ◽

...

Keyword(s):

Discriminant Analysis ◽

Shelf Life ◽

Meat Quality ◽

Near Infrared ◽

Nir Spectroscopy ◽

Life Assessment ◽

Chicken Breast ◽

Portable Devices ◽

Physicochemical Processes ◽

Insight Into

Abstract Near-infrared (NIR) spectroscopy is a rapid technique able to assess meat quality even if its capability to determine the shelf life of chicken fresh cuts is still debated, especially for portable devices. The aim of the study was to compare bench-top and portable NIR instruments in discriminating between four chicken breast refrigeration times (RT), coupled with multivariate classifier models. Ninety-six samples were analysed by both NIR tools at 2, 6, 10 and 14 days post-mortem. NIR data were subsequently submitted to partial least squares discriminant analysis (PLS-DA) and canonical discriminant analysis (CDA). The latter was preceded by double feature selection based on Boruta and Stepwise procedures. PLS-DA sorted moderate separation of RT theses, while shelf life assessment was more accurate on application of Stepwise-CDA. Bench-top tool had better performance than portable one, probably because it captured more informative spectral data as shown by the variable importance in projection (VIP) and restricted pool of Stepwise-CDA predictive scores (SPS). NIR tools coupled with a multivariate model provide deep insight into the physicochemical processes occurring during storage. Spectroscopy showed reliable effectiveness to recognise a 7-day shelf life threshold of breasts, suitable for routine at-line application for screening of meat quality.

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Room-Temperature Near-Infrared Metastable Species Measured by Phase-Sensitive Lock-in and Fourier Transform Techniques

Journal of the Chinese Chemical Society ◽

10.1002/jccs.199800075 ◽

1998 ◽

Vol 45 (4) ◽

pp. 503-508 ◽

Cited By ~ 2

Author(s):

Pi-Tai Chou ◽

Youn-Chan Chen ◽

Shu-Juan Chen ◽

Min-Zen Lee ◽

Ching-Yen Wei ◽

...

Keyword(s):

Fourier Transform ◽

Room Temperature ◽

Near Infrared ◽

Phase Sensitive ◽

Lock In

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MR-GUIDED PULSE OXIMETRY IMAGING OF BREAST IN VIVO

Journal of Innovative Optical Health Sciences ◽

10.1142/s1793545811001459 ◽

2011 ◽

Vol 04 (02) ◽

pp. 199-208

Author(s):

ZHIQIU LI ◽

SHUDONG JIANG ◽

VENKATARAMANAN KRISHNASWAMY ◽

SCOTT C. DAVIS ◽

SUBHADRA SRINIVASAN ◽

...

Keyword(s):

Breast Tissue ◽

Near Infrared ◽

Imaging System ◽

Structural Information ◽

Human Subjects ◽

Nir Spectroscopy ◽

Tomography System ◽

Finger Pulse ◽

Lock In

A near-infrared (NIR) tomography system with spectrally-encoded sources in two wavelength bands was built to quantify the temporal oxyhemoglobin and deoxyhemoglobin contrast in breast tissue at a 20 Hz bandwidth. The system was integrated into a 3 T magnetic resonance (MR) imaging system through a customized breast coil interface for simultaneous optical and MRI acquisition. In this configuration, the MR images provide breast tissue structural information for NIR spectroscopy of adipose and fibro-glandular tissue in breast. Spectral characterization performance of the NIR system was verified through dynamic phantom experiments. Normal human subjects were imaged with finger pulse oximeter (PO) plethysmogram synchronized to the NIR system to provide a frequency-locked reference. Both the raw data from the NIR system and the recovered absorption coefficients of the breast at two wavelengths showed the same frequency of about 1.3 Hz as the PO output. The frequency lock-in approach provided a practical platform for MR-localized recovery of small pulsatile variations of oxyhemoglobin and deoxyhemoglobin in the breast, which are related to the heartbeat and vascular resistance of the tissue.

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