Red Light-emitting Diodes Research Articles

Realizing Highly Stable Quasi-2D Blue Perovskite Light-Emitting Diodes Using Energy Cascades Generated by Biomolecule-Derived Plasmonic Nanostructures.

Blue perovskite light-emitting diodes (LEDs) lag behind green and red LEDs, which have made considerable strides in efficiency and stability. The main disadvantage is its unmodulated phase domains and low energy transfer efficiency, which impede the efficiency, optical purity, and operational stability of the devices. Herein, we show that using biomolecule-derived plasmonic nanostructures can significantly promote defect passivation, van der Waals gap reduction, and cascade energy transfer through synergistic small-molecule interactions and localized surface plasmonic contributions, thereby improving the electroluminescence (EL) properties and operational stability. The designed blue quasi-2D perovskite LED benefits from the synergistic effect with a higher external quantum efficiency (EQE = 3.51%), EL spectral stability, and superior long-term operational stability. These results validate the optimization of structural and energy cascades of quasi-2D perovskites through a simple and environmentally friendly biomolecular tailorable plasmonic nanostructure approach, paving the way for the development of sustainable electronics.

520 nm and 660 nm light-emitting diodes modulates pancreatic development and beta cell functions in zebrafish embryos.

Green and Red LEDs increase insulin production, but their comparative effects on pancreatic and beta cell development are unclear. Zebrafish embryos were divided into three groups: Control (n = 60), Green (G) (n = 60), and Red (R) (n = 60), then irradiated for three days (14 hours/day) with 0.5 W/cm2 G (λpeak = 520 nm, 180 mA) and R (λpeak = 660 nm, 210 mA). At the end of 72 h, pancreatic and beta cells, circadian rhythm, and oxidative stress gene were analyzed using RT-PCR. Malondialdehyde, nitric oxide, superoxide dismutase, and glutathione levels were also evaluated. In the Red group, pancreatic area increased by ~97.13% compared to the Control group and by approximately ~62.16% compared to the G group (both p < 0.0001), and no significant difference in beta cell area (p = 0.964). G group insulin expression increased 2.31-fold compared to R group (p < 0.0001). Red LED treatment increased MDA levels (p < 0.001), oxidative stress (fth1b, nqo1) (p < 0.0001), and per1b during the photophase (p < 0.0001) compared to G group. R LED treatment increases oxidative stress and disrupts circadian rhythm, leading to reduced insulin secretion. The positive effects of G LED treatment have potential for metabolic syndrome, diabetes, and pancreatic diseases.

Photobiomodulation therapy at 650 nm enhances osteogenic differentiation of osteoporotic bone marrow mesenchymal stem cells through modulating autophagy

BackgroundPhotobiomodulatiom therapy (PBMT) has biostimulatory effects on bone marrow mesenchymal stem cells (BMSCs), which takes a pivotal role in maintaining bone mass and avoiding osteoporosis (OP). Autophagy is an important regulator for cell survival and homeostasis. Previous researchers found that BMSCs derived from osteoporotic rats (OP-BMSCs) were with the feature of reduced osteogenic differentiation and autophagy dysfunction. However, the potential regulation of PBMT in osteogenic differentiation of OP-BMSCs and its underling relationship with autophagy remain unclear. Methods650 nm red light-emitting diode (LED) was selected to initiate PBMT effects. The isolation and culture of OP-BMSCs were implemented after the establishment of the OP rat model. Firstly, the optimal dose of LED was screened on OP-BMSCs by CCK-8. Meanwhile, the osteogenic and mineralization activities were studied through the detection of Alkaline phosphatase (ALP) and alizarin red S (ARS). Then, the levels of osteogenesis and autophagy were investigated via western blot and immunofluorescence staining. Finally, the autophagy inhibitor 3-MA was applied to illustrate the underlying mechanism of the osteogenic effect of PBMT on OP-BMSCs. ResultsFirstly, the optimal dose of 6 J/cm2 LED was selected in the subsequent experiments according to CCK-8. Then, the ALP activity and the mineralization ability of OP-BMSCs were obviously increased by PBMT. Meanwhile, Runx-2, OCN and OPN were significantly upregulated in LED group. Furthermore, the expressions of autophagic proteins were significantly increased in LED group by immunofluorescence staining and western blot assay. At last, the promoted effects of PBMT on osteogenic differentiation in OP-BMSCs were distinctly reversed via inhibiting autophagy. ConclusionOur research illustrated that 650 nm LED could improve osteogenic differentiation of OP-BMSCs, suggesting a potential correlation between PBMT-mediated activation of autophagy and promotion of osteogenic differentiation.

High-Performance Red Quantum Dot Light-Emitting Diodes via Exciton Harvesting Based on All-Organic Charge Transport Layers

High-Performance Red Quantum Dot Light-Emitting Diodes via Exciton Harvesting Based on All-Organic Charge Transport Layers

The effect of supplemental LED lighting in the range of UV, blue, and red wavelengths at different ratios on the accumulation of phenolic compounds in pak choi and swiss chard

Phenolic compounds are known for their health-promoting effects on humans. Pak choi (Brassica rapa ssp. chinensis) and Swiss chard (Beta vulgaris subsp. vulgaris) are used here as model plants, as they are eaten raw as baby leaf lettuce and differ in their phenolic compound profile while showing similar morphology. In a greenhouse an artificial light source with UV-B (215 mW m−2), blue (104 μmol/m−2 s−1) and red (245 μmol/m−2 s−1) LEDs was implemented to increase phenolic compounds during the last days before harvest. Pak choi shows an increase or trend towards an increase in the monoacylated triglycosides of kaempferol and quercetin after 4 days of irradiation for 4 h each. For example kaempferol-3-caffeoyl-sophoroside-7-glucoside was increased at low PAR values in the third run and red-dominated light treatment by up to 120 %. In addition, it was observed that the red variety ‘Amur’ has higher concentrations of quercetin glycosides which were increased often. In swiss chard, on the other hand, there was only a sporadic increase in vitexin glycosides. Despite very different concentrations in some samples, 2″-glucosyl-vitexin and 2′′-glucosyl-6′′-malonyl-vitexin showed significant increases of up to 350 % in the two chard varieties Lukullus and Rhubarb chard. The results suggest that the exposure time or intensity of UV-B radiation needs to be optimized for each species and has not yet consistently led to an increase but trends in phenolic compounds and in antioxidant activity in this study.

474 Changes of surface temperature of different materials under irradiation by a red light photodynamic therapy LED lamp

474 Changes of surface temperature of different materials under irradiation by a red light photodynamic therapy LED lamp

Investigation of the Electrochemical Performance of Manganese Based Layered Double Hydroxides for Energy Storage Applications

Supercapacitors are a rapidly evolving technology with immense potential for applications requiring fast energy exchange and high-power delivery. They hold promise for revolutionizing areas like electric vehicles, renewable energy integration, and portable electronics. Layered double hydroxides (LDHs) offer several advantages as supercapacitor electrodes. Unlike batteries that rely on bulk reactions, LDHs store energy through surface interactions, enabling supercapacitors made with LDHs to charge and discharge very quickly. In this work, NiMn, CuMn and CoMn LDHs, which are promising materials for supercapacitor electrodes, are synthesized using an easy hydrothermal method. NiMn LDHs were made with a constant 3:1 Ni:Mn ratio during a range of synthesis timeframes, including 3, 5, 6, and 8 hrs. After electrochemical analysis, NiMn LDH-6 was discovered to have a maximum specific capacitance of 90 F g-1 at 10 mV s-1 as well as exceptional energy and power densities of 6.2 Wh kg-1 and 165.6 W kg-1, respectively. It is noteworthy that CoMn LDH, which was synthesized in the same conditions for six hours, performed even better, with specific capacitance of 104.93 F g-1, energy density of 7.39 Wh kg-1 with a power density of 132.48 W kg-1. An LED set up was activated to demonstrate the practical energy storage uses of CoMn LDH-6 with three supercapacitor cells attached in series. Using this set up, seven red LEDs lighted for 3 mins and twelve green LEDs for 2 mins. The present work underscores the vital function of synthesis time in enhancing the performance of NiMn LDH and showcases the capability of CoMn LDH as an expanded alternative for supercapacitor applications.

FPGA-Based Design for Digital Speedometer to Detect Speed Limit of Vehicles

This paper presents a proposed design for a digital speedometer using Field Programmable Gate Array (FPGA) technology. The speedometer is a crucial safety feature in vehicles, providing real-time information on the vehicle's speed in kilometres per hour (km/h). The objective of this design is to assist drivers in monitoring and controlling their velocity at regular intervals to ensure safe driving. The hardware platform chosen for implementation is the Altera DE2 Board with Cyclone IV E and the hardware description language used is Verilog HDL. The digital speedometer receives a square wave pulse as an input signal from a hall sensor, which is emitted based on the vehicle's speed. The designed system accurately detects and counts these pulses to convert them into the corresponding speed of the vehicle. This digital speedometer is specifically intended for vehicles with engine capacities (cc) ranging from 1000cc to 1300cc. It can detect speeds within the range of 0km/h to 255km/h. The speed value is displayed on a seven-segment display with precision. Additionally, if the vehicle's speed exceeds the expressway's speed limit of 110km/h, a red LED indicator turns on to alert the driver to control their speed.

Synergetic effect driven LaMnO3@NiO composite based high energy semi-solid supercapacitor

Perovskite materials have gained substantial attention in last two decades as electrode materials for energy storage devices due to low cost, good electrochemical stability, mixed ionic-electronic conductivity, long-term stability, and environmentally friendly. We demonstrate the hybridization of lanthanum manganite (LaMnO3) and Nickel oxide (NiO) composite electrodes for supercapacitor application prepared via sol-gel assisted hydrothermal method. The structural, morphological, surface area, and elemental analysis has been done by X-ray diffraction, Field emission scanning electron microscopy, Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS) analysis. The structural, and morphological analysis confirmed the composite formation. The electrochemical properties have been examined by cyclic voltammetry, galvanostatic charge-discharge, and impedance analysis. The resulting LaMnO3/NiO composite material exhibits enhanced electrochemical performance compared to the individual components. The composite exhibits a specific capacitance of up to 170 F/g at a scan rate of 10 mV/s, which is higher than that of individual LaMnO3 or NiO materials. The composite also demonstrates desirable cycling stability, with a capacity retention of 76 % after 5000 cycles. These results advocate that the LaMnO3/NiO composite is a promising material for high-energy supercapacitor applications. Further performance of the nano-composite was evaluated by LED testing. Three symmetric SCs of the composite linked in series were able to glow a green, red, blue LED for about 1 min and a panel of 26 red LED was illuminated for about 12 min. These findings suggested that the obtained composite material is an exceptional electrode with huge potential for potential for supercapacitor application.

Fabrication of MnCo2O4@PANI nanocomposites as electrode material for high-energy density asymmetric supercapacitor

In this work, the co-precipitation method has been utilized to synthesize MnCo2O4 (MCO) and MnCo2O4@Polyaniline (PMCO) nanocomposites. The wt% of polyaniline (PANI) has been varied from 0 to 30 %, keeping the MnCo2O4 precursor quantity constant. The nanocomposite with 20 wt% PANI (P20MCO) exhibits better electrochemical properties compared to other synthesized nanocomposite samples. The P20MCO nanocomposite exhibits specific capacitances of 765 F g−1 at 0.5 A g−1 and 88.13 % capacitance retention over 10,000 consecutive cycles. An asymmetric supercapacitor (ASC) has been constructed using P20MCO as cathode and commercially activated carbon as anode. The fabricated ASC device exhibits outstanding cycling stability with 91.48 % capacitance retention for 45,000 cycles at 12 A g−1. The ASC has the highest power density of 14.3 kW kg−1 and specific energy density of 58 Wh kg−1. Moreover, a red LED is illuminated by a single device and putting two devices in series light the blue, green, and white LEDs. These ASCs glow a red LED for more than 13 min. Our results suggest that the P20MCO nanocomposite-based supercapacitor devices will be promising for energy storage applications because of their easy production approach and good electrochemical performance.

Conditions for thermally stable color characteristics of trichromatic white light-emitting diodes

We present a method to stabilize color characteristics from a trichromatic white light-emitting diode (LED) consisting of red, green, and blue (RGB) LEDs under varying ambient temperatures. Through colorimetric analyses, it was found that the trichromatic white LED could maintain its chromaticity coordinate by adjusting the light output power (LOP) of green and red LEDs as the temperature varied. Moreover, the correlated color temperature (CCT) could be invariant to the external temperature change by controlling only the LOP of a red LED. Using the developed mathematical model and temperature-dependent spectral data of commercial RGB LED samples, we determined the power ratios between RGB LEDs needed to achieve thermally stable color coordinates or CCT as the heat sink temperature varied from 20 to 100 °C. When operating under thermally stable CCT conditions, the chromaticity coordinate of the trichromatic LED moved along the iso-CCT line with only a minor color deviation as the temperature increased to 100 °C. The presented approach requires adjusting the power of only one LED to achieve thermally stable CCT operation in a trichromatic white LED, which is expected to simplify LED control circuits significantly.

Rational design of hierarchical reduced graphene oxide/Ni(OH)2 heterojunction with long cycle life for high-performance hybrid supercapacitors

As a promising electrode material for supercapacitors, Ni(OH)2 is very attractive owing to its superior theoretical specific capacitance; however, its inferior cycling stability remains a barrier. Herein, we constructed a reduced graphene oxide (rGO)/Ni(OH)2 heterojunction via a facile electrostatic self-assembly route, in which Ni(OH)2 nanoflakes were planted on the surface of the rGO substrate, resulting in an increased specific surface area and accelerated electron/ion transport while inheriting the outstanding cycling stability of rGO. The optimal rGO/Ni(OH)2 electrode afforded a great specific capacitance of 2251.6 F/g at 2 A/g and a remarkable cycling stability of ∼104.9 % after 5000 cycles. The rGO/Ni(OH)2//activated carbon hybrid supercapacitor (HSC) achieved an outstanding energy density of 35.4 Wh/kg at 775 W/kg and a cycling durability of ∼98.8 % after 10,000 cycles. Furthermore, two HSCs were connected in series to light 27 parallel red LEDs for more than 210 s, exhibiting enormous application prospects in supercapacitors.

Optimizing Red Light-Based Photodynamic Therapy for Effective Bactericidal Action Against Fusobacterium nucleatum Subspecies.

Fusobacterium nucleatum (F. nucleatum), a key pathogen implicated in periodontal disease, contributes to oral biofilm maturation and is linked to development of systemic diseases like colorectal cancer and liver cirrhosis. Photodynamic therapy (PDT) combined with 5-aminolevulinic acid (5-ALA) treatment (ALA-PDT) selectively targets F. nucleatum by inducing porphyrin accumulation. The bactericidal effect of red light-based PDT on F. nucleatum has not been evaluated previously. This study investigates the effect of ALA-PDT using red light-emitting diode (LED) light on F. nucleatum subspecies and their porphyrin accumulation. F. nucleatum subspecies were cultured with varying concentrations of 5-ALA under anaerobic conditions. Porphyrin accumulation was measured via fluorescence spectroscopy, and colony-forming units were measured to determine bacterial viability post-treatment. Additionally, other subspecies responded well to 0.01% 5-ALA, and uroporphyrin I accumulation correlated with bacterial death, revealing optimal bactericidal conditions. These results suggest that optimizing light intensity and 5-ALA concentration can significantly enhance the therapeutic potential of ALA-PDT in oral healthcare.

Effective Survey Methods for the Elusive Data Deficient Black Flying Squirrel (Aeromys tephromelas) in Sabah, Malaysia Facilitate First Vocalisation Record.

Flying squirrels are nocturnal, gliding relatives of tree and ground squirrels (order Sciuridae). Despite 49 species existing, literature on Asiatic flying squirrels is scarce, thus they are overlooked in conservation action plans. Recently, three species of giant flying squirrel (Aeromys tephromelas, Petaurista petaurista and Aeromys thomasi) were observed during a nocturnal mammal survey at the Rainforest Discovery Centre (RDC), an Eco centre at the edge of the Kabili-Sepilok forest reserve in Sepilok, Sabah (Malaysia, Borneo). The survey (February-March 2023) incorporated the use of red LED spotlighting, thermal imaging and bioacoustic recording during systematic along-line point counts. This is the first report on flying squirrel ecology in Sabah and the first focused publication on the 'giant' black flying squirrel (A. tephromelas), categorised by the IUCN as Data Deficient. The most notable result was the first documentation of a black flying squirrel vocalisation event (106 calls at a frequency range of 0.75-2.69 kHz and mean duration of 1.4 s). Although call function was not determined, this result sheds light on a previously unknown part of their ecology. These results stress the urgency for further research on the black flying squirrel to evaluate their current extinction risk, considering deforestation is prevalent across most of their distribution.

Вплив червоного та синього електромагнітного випромінювання на каталазну активність зародків в’юна Misgurnus fossilis L.

Photobiomodulation therapy is widely used to treat various pathological conditions. This therapy is based on the use of monochromatic light radiation. The light of the visible spectrum induces different biological effects at the molecular and cellular levels, both therapeutic and toxic. The obtained effect depends on the length of radiation, exposure, etc. One of the possible mechanisms of such influence is the regulation of pro-oxidant-antioxidant homeostasis. In order to clarify the mechanism of action of electromagnetic radiation (EMR) of different spectral composition, catalase (CAT) activity was investigated in germ cells of loach Misgurnus fossilis L. during embryogenesis. Since, loach embryos are an adequate system that reflects the physiological state of the cell both under normal conditions and as a result of the influence of various pharmacological, physical and chemical agents. The resulting zygotes were irradiated (10 min) with blue and red LEDs (λ = 460 and 660 nm, respectively). The activity of CAT was determined by the ability of hydrogen peroxi­de to form a stable colored complex with molybdenum salts. It was established that EMR of the red spectrum has the most pronounced biological effects and caused significant changes in catalase activity during embryogenesis relative to control and blue light. The maximum increase of the indicator occurs at the stage of 16 blastomeres, and at the stage of 8 and 10 divisions, a gradual decrease in enzymatic activity is observed. Irradiation by the light of the blue spectrum lasting 10 min did not cause significant changes in catalase activi­ty relative to the control at the early stages of loach embryogenesis. The obtained results suggest that CAT, one of the key enzymes of the antioxidant defense system, undergoes photoactivation under the influence of red light.

Nickel foam supported CuO/Co3O4/r-GO is used as electrode material for non-enzymatic glucose sensors and high performance supercapacitors

In order to solve the problem of glucose detection in medical development and meet the urgent demand for new energy storage devices, this paper proposes a new material suitable for glucose sensing and capacitive properties. The sensor was fabricated by depositing Co3O4 nanoparticles onto nickel foam with integrated r-GO via the hydrothermal method, followed by the synthesis of CuO nanoparticles using electroplating. The detection range of the sensor is 0.3–11.3 mM. The sensor's sensitivity is 1000.3 μA mM−1 cm−2, indicating its responsiveness to changes in analyte concentration. In electrochemical test systems, Signal-to-Noise Ratio (SNR) usually represents the relative intensity of the effective current signal and the background noise, reflecting the accuracy and reliability of the measurement. When the SNR is three, the minimum detection limit is 0.431 μM, highlighting its ability to reliably detect analytes at low concentrations amidst background noise. According to electrochemical workstation tests, the sensor demonstrates robust stability. Furthermore, the electrode material proves suitable for asymmetric supercapacitor devices, when the current density is 2 Ag−1, the specific capacitance is 660.5 Fg−1. At the same time, we also explore the cyclic stability of the device, which can retain 92.3 % of its initial specific capacitance after 5000 cycles, showing its remarkable long-term stability. In addition, the prepared nanocomposites can also light the red LED light. The results show that the synthesized CuO/Co3O4/r-GO/NF electrode can be used for electrochemical glucose sensing and supercapacitors, and plays an important role as a multi-functional material in the fields of medical, food, electronics, transportation and energy, providing key technical support for a variety of applications.

Multifunctional benzoselenadiazole-capped organic molecule-based nanohybrid for efficient asymmetric supercapacitor and oxygen evolution reaction

Nanostructured hybrid materials have attracted significant interest in the field of energy storage and conversion. To investigate the effect of all nanohybrids on electrochemical properties, we have synthesized organic-inorganic nanohybrids through in situ galvanostatic electrodeposition using a monometallic and bimetallic composition of nickel, cobalt salts and an organic molecule. The electrochemical studies reveal that BSeFY/NCDH (20:20) (BSe = benzo[2,1,3]selenadiazole, F = L-phenylalanine and Y = L-tyrosine; NCDH = nickel‑cobalt double hydroxide) hybrid electrode performs more efficiently than 40:0, 0:40, 10:30, 30:10 and nickel‑cobalt double hydroxide-20:20 (NCDH-20:20) electrodes. The specific capacitance of the 20:20 hybrid electrode is measured to be 1338.46 F/g at 2 A/g current density. The AC/NF negative electrode was made using activated carbon, carbon black and polyvinylidene fluoride (PVDF) in a ratio of 80:15:5. The fabricated asymmetric device reveals the energy density of 35.48 Wh/kg at a power density 751.36 W/kg. Furthermore, the device exhibits a capacitance retention of 91.24 % after 5000 cycles at 7 A/g current density. This fabricated device has the ability to illuminate a red LED and operate a small fan. Furthermore, the designed and fabricated hybrid materials are highly efficient for the oxygen evolution reaction (OER). Among the fabricated materials, the 20:20 hybrid electrode is highly active and achieves a lower overpotential of 240 mV with a low Tafel slope of 62 mV/dec at a current density of 10 mA/cm2. Furthermore, the BSeFY/NCDH (20,20) hybrid is highly robust and shows negligible activity loss after 55 h of chronopotentiometry measurement at 10 mA/cm2 current density. Furthermore, multistep chronopotentiometry was performed in the current density range of 4 to 40 mA/cm2 and the results exhibit that the potential rapidly levels off in the next 400 s due to the robust electrochemical stability, rapid mass and electron transportation ability of 20:20 nanohybrid. Therefore, the electrochemical investigations demonstrate that the bimetallic organic-inorganic nanohybrid is highly active in supercapacitor and OER due to its abundant electrochemical active sites, high conductivity, enhanced Faradaic redox properties, multiple valence transitions and the easy synergistic effect between metal ions and organic moiety.

Time-Domain-Filtered Terahertz Nanoscopy of Intrinsic Light-Matter Interactions.

Terahertz (THz) technology holds great potential across diverse applications, including biosensing and information communications, but conventional far-field techniques are limited by diffraction. Near-field optical microscopy overcomes this barrier through a sharp tip that concentrates incident THz waves into nanometric volumes, detecting scattered near-field to reveal nanoscale optical properties. However, owing to the large THz wavelengths, resonant surface waves arising on the tip and cantilever obscure the intrinsic response. Here we combine near-field microscopy with THz time-domain spectroscopy and implement time-domain filtering with an elongated cantilever to eliminate this artifact, achieving intrinsic nanospectroscopy and nanoimaging. By applying this technique, we distinguish and characterize historical pigments of an ancient sculpture, such as vermilion and red lead, on the nanoscale. We also unravel deep-subwavelength localized resonance modes in THz optical antennas, demonstrating capabilities for THz nanophotonics. Our work advances THz nanoimaging and nanospectroscopy techniques to probe intrinsic nanoscale THz light-matter interactions.

Hierarchical nanostructures of Co(OH)2 on electrospun NiMoO4 nanofibers: Controllable hydrothermal-fabrication and enhanced supercapacitor performance

The reasonable design of high–electrochemical–activity components on one-dimensional nanomaterials to construct core–shell composite materials is an effective approach to optimize the properties of single-component electrode materials. In this study, an NiMoO4@Co(OH)2 composite material featuring a unique core–shell structure was synthesized by combining electrospinning with the hydrothermal synthesis method. The results indicate that the NiMoO4@Co(OH)2 composite exhibits a superior specific capacitance (1357 F/g) at a current density of 1 A/g, and the capacity retention rate remains as high as 80.66 % after 5000 charge/discharge cycles. This superior performance is primarily attributed to the one-dimensional NiMoO4 nanofibers providing a uniform growth template for the Co(OH)2 nanosheets, which substantially enhances the structural stability of the material. Additionally, the introduction of the Co(OH)2 nanosheets significantly increases the specific surface area and theoretical capacitance of the NiMoO4@Co(OH)2 composite, improving its overall performance. The uniform and stable structure, high specific surface area, and numerous active sites of the NiMoO4@Co(OH)2 composite increase the electron transfer rate in the redox reaction and endow the material with excellent electrical conductivity. An asymmetric supercapacitor (ASC) was assembled using the composite material as the positive electrode and activated carbon as the negative electrode. It exhibits a high energy density (56.307 Wh/kg) at a power density of 685 W/kg and a capacity retention rate of 82.35 % after 5000 cycles. Furthermore, by connecting two ASCs in series, a red LED could be lit, proving the application potential of NiMoO4@Co(OH)2 composites for use as electrode materials for ASCs.

Manipulating flavonoid biosynthesis in Trigonella persica through controlled spectral lighting

Trigonella persica Boiss., is renowned for its rich phytochemical profile, particularly the presence of the flavonol quercetin. This study explored the effects of various light treatments, including blue, red, blue-red (1:1) radiation (BRR), and pink fluorescent light (PFL), on the biochemical and molecular mechanisms governing quercetin and flavonoid biosynthesis in T. persica at different growth stages. Our results showed that light treatments significantly influenced the activity of key enzymes phenylalanine ammonia-lyase (PAL) and tyrosine ammonia-lyase (TAL) during germination and vegetative growth, with blue light inducing higher PAL and TAL activities compared to control conditions. High-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) analyses revealed that 48-h-old sprouts grown under red light exhibited the highest levels of flavonoid components and phenolic acids, with catechin as the predominant flavonoid. Notably, BRR treatment led to elevated concentrations of the bioavailable quercetin-3-rhamnoside in 48-h-old sprouts, while 15-day-old plants grown under PFL conditions showed a significant accumulation of the sulfated quercetin-3-sulfate. Real-time PCR analysis demonstrated that BRR upregulated the expression of flavonoid biosynthesis genes PAL, chalcone synthase (CHS), and chalcone isomerase (CHI) in sprouts, whereas PFL treatment induced higher expression of these genes, as well as cinnamate 4-hydroxylase (C4H), in aerial parts. These findings suggest that targeted light treatments, particularly blue and red LED light, can enhance the accumulation of bioavailable quercetin-3-rhamnoside during T. persica germination and sprouts exhibit higher levels of flavonoids and phenolic acids than aerial parts during different vegetative growth stages.