Blue Light-Activated Riboflavin Phosphate Promotes Collagen Crosslinking to Modify the Properties of Connective Tissues

Reduced amounts of collagen and fragmented collagen fibers are characteristics of aging skin. Recently, user-friendly, at-home personal aesthetic devices using light-emitting diode (LED) light have been used for cost-effective and safe skin improvement. However, to dramatically improve the skin via collagen repair, we need to develop an LED-responsive photosensitizer. Corneal collagen crosslinking uses ultraviolet light to activate riboflavin phosphate (RFP) and is used in ophthalmology. RFP is a biocompatible photosensitizer derived from vitamin B2. This study aimed to prove that RFP combined with blue light (BL) can increase collagen crosslinking density, improving its mechanical properties in skin tissue and enhancing skin elasticity. We confirmed the RFP-induced photo-crosslinking in pure collagen by studying changes in its dynamic modulus and matrix morphology using collagen hydrogels. We also measured the changes in the mechanical properties after applying photo-crosslinking on porcine skin. The Young’s modulus (1.07 ± 0.12 MPa) and tensile strength (11.04 ± 1.06 MPa) of the porcine skin after photo-crosslinking were 2.8 and 3.5 times better compared to those of normal porcine skin, respectively. Thus, photo-crosslinking through RFP and BL irradiation can be potentially used for skin improvement using aesthetic LED devices.

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Silicon-Based Blue Light Emitting Diode

10.21236/ada282382 ◽

1993 ◽

Author(s):

SPIRE CORP BEDFORD MA

Keyword(s):

Blue Light ◽

Light Emitting Diode ◽

Light Emitting ◽

Silicon Based

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In vitro and in vivo Efficacy of New Blue Light Emitting Diode Phototherapy Compared to Conventional Halogen Quartz Phototherapy for Neonatal Jaundice

Journal of Korean Medical Science ◽

10.3346/jkms.2005.20.1.61 ◽

2005 ◽

Vol 20 (1) ◽

pp. 61 ◽

Cited By ~ 23

Author(s):

Yun Sil Chang ◽

Jong Hee Hwang ◽

Hyuk Nam Kwon ◽

Chang Won Choi ◽

Sun Young Ko ◽

...

Keyword(s):

Blue Light ◽

Neonatal Jaundice ◽

Light Emitting Diode ◽

In Vivo Efficacy ◽

Light Emitting

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Operando direct observation of spin-states and charge-trappings of blue light-emitting-diode materials in thin-film devices

Scientific Reports ◽

10.1038/s41598-020-75668-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Fumiya Osawa ◽

Kazuhiro Marumoto

Keyword(s):

Blue Light ◽

High Performance ◽

Density Functional ◽

Light Emitting Diode ◽

Green Light ◽

Spin States ◽

Light Emitting ◽

Full Color ◽

Color Displays ◽

Materials Used

Abstract Spin-states and charge-trappings in blue organic light-emitting diodes (OLEDs) are important issues for developing high-device-performance application such as full-color displays and white illumination. However, they have not yet been completely clarified because of the lack of a study from a microscopic viewpoint. Here, we report operando electron spin resonance (ESR) spectroscopy to investigate the spin-states and charge-trappings in organic semiconductor materials used for blue OLEDs such as a blue light-emitting material 1-bis(2-naphthyl)anthracene (ADN) using metal–insulator–semiconductor (MIS) diodes, hole or electron only devices, and blue OLEDs from the microscopic viewpoint. We have clarified spin-states of electrically accumulated holes and electrons and their charge-trappings in the MIS diodes at the molecular level by directly observing their electrically-induced ESR signals; the spin-states are well reproduced by density functional theory. In contrast to a green light-emitting material, the ADN radical anions largely accumulate in the film, which will cause the large degradation of the molecule and devices. The result will give deeper understanding of blue OLEDs and be useful for developing high-performance and durable devices.

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Optimization and evaluation of a blue light photoinitiating system for textile inkjet printing

Textile Research Journal ◽

10.1177/0040517518783346 ◽

2018 ◽

Vol 89 (10) ◽

pp. 1964-1974

Author(s):

Yi Huang ◽

Guangdong Sun ◽

Yating Ji ◽

Dapeng Li ◽

Qinguo Fan ◽

...

Keyword(s):

Blue Light ◽

Light Emitting Diode ◽

Absorption Efficiency ◽

Polymerization Rate ◽

Nozzle Clogging ◽

Light Emitting ◽

Custom Made ◽

Light Curing ◽

Set Up ◽

Pigment Ink

A blue light curing process was developed to solve the nozzle clogging challenge commonly encountered in conventional textile pigment printing, by using camphorquinone (CQ) and ethyl-4-dimethylaminobenzoate (EDMAB) as a photoinitiator combination and substituting oligomers and monomers for a polymeric binder. High light absorption efficiency was insured by closely matching the spectrum of the photoinitiator with a custom-made blue light light-emitting diode set-up. Kinetic analyses of such a CQ/EDMAB system indicated that the maximum polymerization rate of the monomer was proportional to [PI]0.5 and [I0]0.5, while excessive high photoinitiator concentration (>1 wt%) will decrease the polymerization rate because of the “filter effect.” With optimized blue light curable pigment ink formula and irradiation conditions, the photocurable pigment printed fabrics exhibited uniform and vibrant colors, clear outlines, and excellent wet and dry rubbing fastness of grades 4 and 4–5, respectively.

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Homogeneous ZnO nanowire arrays p-n junction for blue light-emitting diode applications

Optics Express ◽

10.1364/oe.27.0a1207 ◽

2019 ◽

Vol 27 (16) ◽

pp. A1207 ◽

Cited By ~ 7

Author(s):

Mingming Su ◽

Tanglei Zhang ◽

Jun Su ◽

Zhao Wang ◽

Yongming Hu ◽

...

Keyword(s):

Blue Light ◽

Light Emitting Diode ◽

Nanowire Arrays ◽

Zno Nanowire ◽

Light Emitting ◽

Zno Nanowire Arrays

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Enhanced performances of InGaN/GaN-based blue light-emitting diode with InGaN/AlInGaN superlattice electron blocking layer

Chinese Physics B ◽

10.1088/1674-1056/23/6/068502 ◽

2014 ◽

Vol 23 (6) ◽

pp. 068502

Author(s):

Xiang-Jing Zhuo ◽

Jun Zhang ◽

Dan-Wei Li ◽

Han-Xiang Yi ◽

Zhi-Wei Ren ◽

...

Keyword(s):

Blue Light ◽

Light Emitting Diode ◽

Blocking Layer ◽

Electron Blocking Layer ◽

Light Emitting

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Low Cost Cooling Device for High Power LED Lamps

Volume 11: Heat Transfer and Thermal Engineering ◽

10.1115/imece2020-24630 ◽

2020 ◽

Author(s):

Pamela Martinez-Vega ◽

Araceli Lopez-Badillo ◽

J. Luis Luviano-Ortiz ◽

Abel Hernandez-Guerrero ◽

Jaime G. Cervantes

Keyword(s):

Reference Model ◽

Light Emitting Diode ◽

Low Cost ◽

Cost Effective ◽

Heat Sinks ◽

Modern World ◽

Type Model ◽

Light Emitting

Abstract The modern world progressively demands more energy; according to forecasts energy consumption will grow at an average annual rate of 3 percent. Therefore, it is necessary to purchase products or devices that are efficient and environmentally friendly. Technology in LED (Light Emitting Diode) lighting is presented as an alternative to energy saving, since LEDs have proven to be extremely efficient, have a long service life and their cost-effective ratio is very good. However, the heat emitted by the LED chip must be dissipated effectively, since the overheating of the chip reduces the efficiency and lifetime of the lamp. Therefore, heat sinks that are reliable, efficient and inexpensive should be designed and built. The present work proposes new designs for heat sinks in LED lamps, some of the models in the design of the fins refer to the Fibonacci series. The models proposed in the present work that have a significant advantage are the Type 1E Model (5.2% mass savings and better thermal efficiency of 8.33%), GR Type 1 Model (3.12% lighter and 3.33% more efficient) and the GRL Type Model (4. 51% mass savings and 5.55% thermally more efficient) compared to the Type 2 Reference Model proposed by Jang et al. [12].

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