Battery-free, lightweight, injectable microsystem for in vivo wireless pharmacology and optogenetics

Pharmacology and optogenetics are widely used in neuroscience research to study the central and peripheral nervous systems. While both approaches allow for sophisticated studies of neural circuitry, continued advances are, in part, hampered by technology limitations associated with requirements for physical tethers that connect external equipment to rigid probes inserted into delicate regions of the brain. The results can lead to tissue damage and alterations in behavioral tasks and natural movements, with additional difficulties in use for studies that involve social interactions and/or motions in complex 3-dimensional environments. These disadvantages are particularly pronounced in research that demands combined optogenetic and pharmacological functions in a single experiment. Here, we present a lightweight, wireless, battery-free injectable microsystem that combines soft microfluidic and microscale inorganic light-emitting diode probes for programmable pharmacology and optogenetics, designed to offer the features of drug refillability and adjustable flow rates, together with programmable control over the temporal profiles. The technology has potential for large-scale manufacturing and broad distribution to the neuroscience community, with capabilities in targeting specific neuronal populations in freely moving animals. In addition, the same platform can easily be adapted for a wide range of other types of passive or active electronic functions, including electrical stimulation.

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Implantable Optrode Array for Optogenetic Modulation and Electrical Neural Recording

Micromachines ◽

10.3390/mi12060725 ◽

2021 ◽

Vol 12 (6) ◽

pp. 725

Author(s):

Saeyeong Jeon ◽

Youjin Lee ◽

Daeho Ryu ◽

Yoon Kyung Cho ◽

Yena Lee ◽

...

Keyword(s):

Light Emitting Diode ◽

Neural Recording ◽

Electrophysiological Recording ◽

Light Emitting ◽

Technological Advances ◽

Neuroscience Research ◽

Cell Type Specific ◽

Novel Design

During the last decade, optogenetics has become an essential tool for neuroscience research due to its unrivaled feature of cell-type-specific neuromodulation. There have been several technological advances in light delivery devices. Among them, the combination of optogenetics and electrophysiology provides an opportunity for facilitating optogenetic approaches. In this study, a novel design of an optrode array was proposed for realizing optical modulation and electrophysiological recording. A 4 × 4 optrode array and five-channel recording electrodes were assembled as a disposable part, while a reusable part comprised an LED (light-emitting diode) source and a power line. After the characterization of the intensity of the light delivered at the fiber tips, in vivo animal experiment was performed with transgenic mice expressing channelrhodopsin, showing the effectiveness of optical activation and neural recording.

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BiPOLES: a tool for bidirectional dual-color optogenetic control of neurons

10.1101/2020.07.15.204347 ◽

2020 ◽

Author(s):

Johannes Vierock ◽

Silvia Rodriguez-Rozada ◽

Florian Pieper ◽

Alexander Dieter ◽

Amelie Bergs ◽

...

Keyword(s):

Neuronal Activity ◽

Red Light ◽

Single Experiment ◽

Neuronal Populations ◽

Dual Color ◽

Neuroscience Research ◽

New Applications ◽

Large Repertoire ◽

Optogenetic Control

AbstractOptogenetic manipulation of neuronal activity has become an indispensable experimental strategy in neuroscience research. A large repertoire of excitatory and inhibitory tools allows precise activation or inhibition of genetically targetable neuronal populations. However, an optogenetic tool for reliable bidirectional control of neuronal activity allowing both up- and downregulation of the same neurons in a single experiment is still missing. Here we report BiPOLES, an optogenetic tool for potent excitation and inhibition of the same population of neurons with light of two different colors. BiPOLES consists of an inhibitory, blue-light-sensitive anion-conducting channelrhodopsin fused to an excitatory, red-light-sensitive cation-conducting channelrhodopsin in a single, trafficking-optimized tandem protein. BiPOLES enables multiple new applications including potent dual-color spiking and silencing of the same neurons in vivo and dual-color optogenetic control of two independent neuronal populations.

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LED Rail Signals: Full Hardware Realization of Apparatus with Independent Intensity by Temperature Changes

Electronics ◽

10.3390/electronics10111291 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1291

Author(s):

Giuseppe Schirripa Schirripa Spagnolo ◽

Fabio Leccese

Keyword(s):

Temperature Sensor ◽

Energy Efficient ◽

Light Emitting Diode ◽

Junction Temperature ◽

Light Emitting ◽

Temperature Changes ◽

Wide Range ◽

International Regulations ◽

Long Lifetime ◽

Set Up

Nowadays, signal lights are made using light-emitting diode arrays (LEDs). These devices are extremely energy efficient and have a very long lifetime. Unfortunately, especially for yellow/amber LEDs, the intensity of the light is closely related to the junction temperature. This makes it difficult to design signal lights to be used in naval, road, railway, and aeronautical sectors, capable of fully respecting national and international regulations. Furthermore, the limitations prescribed by the standards must be respected in a wide range of temperature variations. In other words, in the signaling apparatuses, a system that varies the light intensity emitted according to the operating temperature is useful/necessary. In this paper, we propose a simple and effective solution. In order to adjust the intensity of the light emitted by the LEDs, we use an LED identical to those used to emit light as a temperature sensor. The proposed system was created and tested in the laboratory. As the same device as the ones to be controlled is used as the temperature sensor, the system is very stable and easy to set up.

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Near Unity PLQY and High Stability of Barium Thiocyanate Based All-Inorganic Perovskites and Their Applications in White Light-Emitting Diodes

Photonics ◽

10.3390/photonics8060209 ◽

2021 ◽

Vol 8 (6) ◽

pp. 209

Author(s):

Gopi Chandra Adhikari ◽

Saroj Thapa ◽

Yang Yue ◽

Hongyang Zhu ◽

Peifen Zhu

Keyword(s):

White Light ◽

Large Scale ◽

Light Emitting Diode ◽

Photophysical Properties ◽

Environmental Stability ◽

Color Temperature ◽

Ambient Atmosphere ◽

Light Emitting ◽

Halide Perovskite ◽

Lead Halide

All-inorganic lead halide perovskite (CsPbX3) nanocrystals (NCs) have emerged as a highly promising new generation of light emitters due to their extraordinary photophysical properties. However, the performance of these semiconducting NCs is undermined due to the inherent toxicity of lead and long-term environmental stability. Here, we report the addition of B-site cation and X-site anion (pseudo-halide) concurrently using Ba(SCN)2 (≤50%) in CsPbX3 NCs to reduce the lead and improve the photophysical properties and stability. The as-grown particles demonstrated an analogous structure with an almost identical lattice constant and a fluctuation of particle size without altering the morphology of particles. Photoluminescence quantum yield is enhanced up to near unity (~98%) by taking advantage of concomitant doping at the B- and X-site of the structure. Benefitted from the defect reductions and stronger bonding interaction between Pb2+ and SCN− ions, Ba(SCN)2-based NCs exhibit improved stability towards air and moisture compared to the host NCs. The doped NCs retain higher PLQY (as high as seven times) compared to the host NCs) when stored in an ambient atmosphere for more than 176 days. A novel 3D-printed multiplex color conversion layer was used to fabricate a white light-emitting diode (LED). The obtained white light shows a correlated color temperature of 6764 K, a color rendering index of 87, and luminous efficacy of radiation of 333 lm/W. In summary, this work proposes a facile route to treat sensitive lead halide perovskite NCs and to fabricate LEDs by using a low-cost large-scale 3-D printing method, which would serve as a foundation for fabricating high-quality optoelectronic devices for near future lighting technologies.

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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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(Invited) High Brightness, Large Scale GaN Based Light-Emitting Diode Grown on 8-Inch Si Substrate

ECS Transactions ◽

10.1149/06104.0071ecst ◽

2014 ◽

Vol 61 (4) ◽

pp. 71-78

Author(s):

S.-J. Lee ◽

H.-J. Park ◽

J.-B. Park ◽

D.-W. Jeon ◽

J. H. Baek ◽

...

Keyword(s):

Large Scale ◽

Light Emitting Diode ◽

Si Substrate ◽

High Brightness ◽

Light Emitting

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Retinal damage related to high-intensity light-emitting diode exposure: An in vivo study

American Journal of Orthodontics and Dentofacial Orthopedics ◽

10.1016/j.ajodo.2021.01.026 ◽

2021 ◽

Author(s):

Marcela Emílio de Araújo ◽

Marina Bozzini Paies ◽

Ana Beatriz Arrais ◽

Fernando Ladd Lobo ◽

Ruthnaldo Rodrigues Melo de Lima ◽

...

Keyword(s):

High Intensity ◽

Light Emitting Diode ◽

In Vivo Study ◽

Retinal Damage ◽

Light Emitting ◽

High Intensity Light

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Spectroscopy Transmittance by LED Calibration

Sensors ◽

10.3390/s19132951 ◽

2019 ◽

Vol 19 (13) ◽

pp. 2951 ◽

Cited By ~ 3

Author(s):

Daniel Carreres-Prieto ◽

Juan T. García ◽

Fernando Cerdán-Cartagena ◽

Juan Suardiaz-Muro

Keyword(s):

Real Time ◽

Light Emitting Diode ◽

Research Work ◽

Cost Effective ◽

Spectral Width ◽

Calibration Procedure ◽

Pollution Monitoring ◽

Light Emitting ◽

Wide Range ◽

Incandescent Lamps

Local administrations demand real-time and continuous pollution monitoring in sewer networks. Spectroscopy is a non-destructive technique that can be used to continuously monitor quality in sewers. Covering a wide range of wavelengths can be useful for improving pollution characterization in wastewater. Cost-effective and in-sewer spectrophotometers would contribute to accomplishing discharge requirements. Nevertheless, most available spectrometers are based on incandescent lamps, which makes it unfeasible to place them in a sewerage network for real-time monitoring. This research work shows an innovative calibration procedure that allows (Light-Emitting Diode) LED technology to be used as a replacement for traditional incandescent lamps in the development of spectrophotometry equipment. This involves firstly obtaining transmittance values similar to those provided by incandescent lamps, without using any optical components. Secondly, this calibration process enables an increase in the range of wavelengths available (working range) through a better use of the LED’s spectral width, resulting in a significant reduction in the number of LEDs required. Thirdly, this method allows important reductions in costs, dimensions and consumptions to be achieved, making its implementation in a wide variety of environments possible.

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Design of Light Emitting Diodes (LEDs) Lighting System and Its Application in Garden Landscape Decoration

Journal of Nanoelectronics and Optoelectronics ◽

10.1166/jno.2020.2793 ◽

2020 ◽

Vol 15 (6) ◽

pp. 734-742

Author(s):

Hailiang Liu ◽

Jiade Cheng ◽

Asnidar Hanim Yusuf

Keyword(s):

Control System ◽

Large Scale ◽

Light Emitting Diode ◽

Image Data ◽

Junction Temperature ◽

Lighting System ◽

Light Emitting ◽

Led Lighting ◽

Arm Processor ◽

Control Node

Light Emitting Diode (LED) is widely used in garden landscape decoration because of its small size, low power, concentrated light, and the capability of showing more vivid colors. While designing the LED lighting system, considering that a single Advanced RISC Machine (ARM)-based control system cannot achieve large-scale LED display, and a single Field Programmable Gate Array (FPGA)-based control system cannot control the lighting system well, an LED system with the combination of ARM processor-FPGA is proposed. In this system, the ARM processor is used as the major control component. The Linux system realizes remote monitoring and intelligent management of image data. In addition, FPGA is used for LED data output. The lighting system consists of a major control node and a lighting node. The nodes are connected in parallel through a chain network. The major control node uses an ARM Cortex processor and is equipped with a Linux operating system. The lighting node uses ARM + FPGA hardware architecture. During the experiments, the LED lighting system is tested first. The results show that the reading and writing speed is fast. The LED display screen meets the lighting requirements. This LED lighting system is used for night lighting of garden landscapes. During the brightness test, the brightness of lighting objects and the background is used as research objects. Experiments have proved that the ratio of the lighting object brightness to the background brightness between (Yu, M. and Li, X., 2012. A little current k-factor method for measuring junction temperature of aviation lighting power led. Guangxue Jishu/Optical Technique, 38(3), pp.371–375; Monas, A., Verma, A., Gawari, A. and Paswan, R. S., 2016. Portable network monitor using arm processor. Procedia Computer Science, 92, pp.493–497.) is suitable for night lighting of garden landscape decoration, which will not bring discomfort to people who enjoy night scenery.

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