Showing papers on "Ultraviolet light published in 2023"

Ultraviolet light exposure and its penetrance through the eye in a porcine model.

Abstract: AIM To determine the amount of ultraviolet (UV) light irradiance that various layers of the eye receive as sunlight passes through the eye, and to investigate the protective benefits of UV light-blocking contact lenses. METHODS Twenty-four porcine eyes were prepared in one of three ways: isolated cornea, cornea and lens together, or whole eye preparation. UV light irradiance was measured with a UV-A/B light meter before and after the eye preparations were placed over the meter to measure UV light penetration in each eye structure. In the whole eye preparation, a hole was placed in the fovea to measure light as it passed through the vitreous. Subsequently, UV-protective contact lenses were placed over the structures, and UV light penetrance was measured. Measurements of UV light exposure were taken outdoors at various locations and times. RESULTS Cornea absorbed 63.56% of UV light that reached the eye. Cornea and lens absorbed 99.34% of UV light. Whole eye absorbed 99.77% of UV light. When UV-protective contact lenses were placed, absorption was 98.90%, 99.55%, and 99.87%, respectively. UV light exposure was dependent on directionality and time of day, and was greatest in areas of high albedo that reflect significant amounts of light, such as a beach. CONCLUSION Cornea absorbs the majority of UV light that reaches the eye in this model. UV-protective contact lenses reduce UV exposure to the eye. Locations with high albedo expose the eye to higher levels of UV light.

Inverse Opal Photonic Crystals for Real-Time Identifiable Labels via Ultraviolet and Near-Infrared Light

Abstract: In this work, we developed inverse opal photonic crystals (IOPCs) for real-time identifiable labels by tuning the structure color and chemical color under ultraviolet (UV) light and near-infrared (NIR) light. We prepared IOPCs by etching a silica photonic crystal template in thermosensitive hydrogel added to 2,2-diphenyl-2H-naphtho [1,2-b] pyran-6-carbaldehyde (NP). In this way, the transparent hydrogel turned red under UV light due to the photochromic naphthopyran. Meanwhile, the green structure color of IOPCs was superimposed with the red chemical color of the hydrogel, so that IOPCs with naphthopyran (IOPCs/NP) appeared yellow. When irradiated by NIR light, the structure color of IOPCs turned blue from green due to the volume contraction of the thermosensitive hydrogel. When irradiated by UV and NIR light simultaneously, the blue structure color of IOPCs was superimposed with the red chemical color of the hydrogel, and the IOPCs/NP would finally appear purple. Thus, we realized the real-time controllable IOPCs by two light sources. Based on this, we designed a series of identifiable labels with multiple colors under UV and NIR light, which expanded the application of information anticounterfeiting and identification.

Comparative Study of Blue Light with Ultraviolet (UVC) Radiation on Betacoronavirus 1

Abstract: The ongoing coronavirus pandemic requires more effective disinfection methods. Disinfection using ultraviolet light (UV), especially longer UVC wavelengths, such as 254 and 270/280 nm, has been proven to have virucidal properties, but its adverse effects on human skin and eyes limit its use to enclosed, unoccupied spaces. Several studies have shown the effectiveness of blue light (405 nm) against bacteria and fungi, but the virucidal property at 405 nm has not been much investigated. Based on previous studies, visible light mediates inactivation by absorbing the porphyrins and reacting with oxygen to produce reactive oxygen species (ROS). This causes oxidative damage to biomolecules, such as proteins, lipids, and nucleic acids, essential constituents of any virus. The virucidal potential of visible light has been speculated because the virus lacks porphyrins. This study demonstrated porphyrin-independent viral inactivation and conducted a comparative analysis of the effectiveness at 405 nm against other UVC wavelengths. The betacoronavirus 1 (strain OC43) was exposed to 405, 270/280, 254, and 222 nm, and its efficacy was determined using a median tissue culture infectious dose, i.e., TCID50. The results support the disinfection potential of visible light technology by providing a quantitative effect that can serve as the basic groundwork for future visible light inactivation technologies. In the future, blue light technology usage can be widened to hospitals, public places, aircraft cabins, and/or infectious laboratories for disinfection purposes.

Visible-to-UV Photon Upconversion: Recent Progress in New Materials and Applications.

Abstract: Ultraviolet (UV, λ < 400 nm) light is essential for various photochemical reactions, but its intensity in the solar spectrum is very low, and light sources that artificially generate high-energy UV light are inefficient and environmentally unfriendly. A solution to this problem is photon upconversion (UC) from visible (vis, λ > 400 nm) light to UV light. Among several mechanisms, UC based on triplet-triplet annihilation (TTA-UC) in particular has made remarkable progress in recent years. The development of new chromophores has enabled highly efficient conversion of low-intensity visible light into UV light. In this review, we summarize the recent development of visible-to-UV TTA-UC, from the development of chromophores and their production into films to their application in various photochemical processes such as catalysis, bond activation and polymerization. Finally, challenges and opportunities in future material development and applications will be discussed.

Animal Excretions

Abstract: Extract [Liquid Excretions: See Figure 945.88 (see 16.16.01).] [Solid Excretions: See Figure 981.22 (see 16.16.08).] AOAC Official Method 945.88Urine Stains on Foods and Containers: Ultraviolet Light Examination First Action 1945 Final Action 1996 (Applicable to suspect urine stains on all materials except seeds.) Examine suspected stains in dark room under long wave UV light (366 nm). (Dried urine on textiles usually fluoresces blue-white, but color varies somewhat, depending upon natural color of textile and type of lamp and filter used.) Run check patches with known types of urine. For microchemical analysis, outline stained area with pencil under the UV light. When odor of urine is detected, report this. See Figure 945.88. AOAC Official Method 942.24Urine Stains on Foods and Containers: Urease Test for Urea First Action 1942 Final Action 1996 (Applicable to urine residues on materials with significant amounts of interfering substances, i.e., fats and oils.) Cut out portion of stained area and transfer 1 or 2 threads to 5 mL crucible or beaker. Save balance of cloth to confirm urine by 973.64 (see 16.16.07). Leach 10 min in just enough warm water to cover material. Remove threads and squeeze out as much liquid as possible with clean, flat-tip forceps.

Recent Progress of Ultraviolet and Near-ultraviolet Organic Light-emitting Diodes

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Effect of visible light and ultraviolet light on the pathogenicity of entomopathogenic fungi to false codling moth, Thaumatotibia leucotreta (Lepidoptera: Tortricidae) larvae

Abstract: Entomopathogenic fungi (EPF) are effective and environment-friendly insect biological control agents. Ultraviolet (UV) light is known to have an effect on the survival of fungal conidia, and natural sunlight is potentially one of the most damaging factors undermining EPF persistence and pathogenicity. This study aimed to test the infection potential of an isolate of Beauveria bassiana and five Metarhizium species after exposure to different light treatments, on soil and leaf surfaces under laboratory and field conditions, using Thaumatotibia leucotreta (Lepidoptera: Tortricidae) as the test host. Conidia were exposed either to growth light alone, which emits the same visible light as the sun, but excluding UV light, or directly exposed to UV light for 12 h. The results indicated no negative effect on the infection potential of the conidia of most species tested. The conidia of the two Metarhizium pinghaense (5HEID and TH149) isolates showed the greatest tolerance to visible light and UV radiation exposure on both soil and leaf surfaces. Exposure of M. pinghaense isolates to visible light on soil surfaces showed pathogenicity of > 80% for both isolates, and of between 58% and 88% after exposure to UV light. On leaf surfaces, three Metarhizium isolates, M. pinghaense (5HEID and TH149) and M. majus (TH153) had > 90% pathogenicity following exposure to UV light, and M. pinghaense (TH149) and M. robertsii (6EIKEN) showed greater tolerance of > 70%, under laboratory conditions. However, the pathogenicity of the EPF isolates was very low in field trials, indicating that further trials on the use of formulations and adjuvants with the isolates are needed to improve long-term persistence and efficacy under field conditions.

Ultraviolet-A Light Dehydration of Purple Potatoes

Abstract: Purple potatoes were dehydrated with a combination of low relative humidity air flow at room temperature and ultraviolet (UV)-A light exposure. The control, dehydrated purple potatoes without UV-A light exposure contained approximately 133% more moisture wet basis than their UV-A light-treated counterparts, which resulted in the removal of 97% of the original mass of water in the UV-A light-treated potatoes. Electron microscopy and infrared spectroscopy analyses confirmed substantial preservation of the physical and chemical integrity of the UV-A light-dehydrated samples even under prolonged storage within a wide range of RH levels (11.3–86%). The UV-A light-dehydrated purple potatoes also preserved to some extent their original color without the need of pretreatments for enzyme inactivation and had significantly higher total phenolics concentration than the raw samples. Differential scanning calorimetry confirmed the preservation of physical integrity through its association with thermal properties.

Rapid synthesis of BaMoO4 :Eu3+ red phosphors by microwave irradiation.

Abstract: In this study, BaMoO4 :Eu3+ red phosphors were synthesized by the microwave method. In addition, the phase composition, morphology, and luminescence properties of the red phosphors were characterized by X-ray diffraction (XRD), field-scanning electron microscopy (FESEM), and photoluminescence spectroscopy. The results revealed that doping red phosphors with different concentrations of Eu3+ does not change the crystal structure of the matrix material. The BaMoO4 :Eu3+ phosphors exhibited micron-scale irregular polyhedra, which could be excited by ultraviolet light with a wavelength of 395 nm to induce red-light emission. The optimal dosage of Eu3+ was 0.08, and the chromaticity coordinates of BaMoO4 :0.08Eu3+ phosphors were (0.5869, 0.3099). White light-emitting diodes (w-LEDs) devices prepared by mixing BaMoO4 :0.08Eu3+ phosphor with commercially available phosphors exhibited good white-light emission performance under the excitation of an ultraviolet chip. The BaMoO4 :0.08Eu3+ red phosphors rapidly synthesized under microwave field are expected to be used in w-LED devices.

Dy 3+ doped Y 2 Zr 2 O 7 highly transparent ceramics for ultraviolet excitable warm white light emitting applications

Abstract: Attaining effective warm white light emitting in functionally advantageous transparent polycrystalline ceramics is vitally important to guarantee the development of both human and botanical systems. In response to this aim, a series of Dy3+ doped Y2Zr2O7 (YZO) transparent ceramics were prepared via a solid-state reaction and vacuum sintering approach in this work. These fabricated ceramics show high transparency, where the in-line transmittance at 700 nm is about 76 %, which is very close to the theoretical limit (78%). In addition, under the excitation of UV light sources (358 nm and 384 nm), strong warm white light emissions were observed in these YZO:Dy transparent ceramics. The corresponding photoluminescence characteristics and mechanisms of YZO:Dy ceramics are investigated carefully. The Dy doped YZO ceramics integrate with high transparency and UV-excitable warm white light emission properties, making them promising light-emitting converter materials for light emitting source applications. This article is protected by copyright. All rights reserved

Field evaluation of newly developed 3D-printed ultraviolet and green light-emitting diode traps for the collection of Culicoides species in Thailand

Abstract: Culcioides biting midges (Diptera: Ceratopogonidae) are vectors of various veterinary pathogens. Suction light traps are one of the most widely used tools for vector surveillance. The present aim was to compare the efficiency for the collection of Culicoides species between newly developed 3D-printed ultraviolet (Mahidol University (MU) UV LED) and green light-emitting diode (Mahidol University (MU) Green LED) traps baited with CO2 and UV LED Center for Disease Control (CDC) light trap (BioQuip 2770) baited with CO2. The experiment consisted of two replicates of a 3 × 3 Latin square design in each three sampling locations (Location 1, 2, 3 and 4, 5, 6), for 12 nights between 26th July and 7th August 2020 in Thailand. Results showed that efficiency of the MU UV LED light trap was equivalent to that of the BioQuip 2770 trap for the collection of Culicoides. Meanwhile, the efficiency of the MU Green LED light trap was lower than that of both UV LED light traps. In the analysis of Culicoides species composition and sex–age grading, a similar pattern was observed among three light traps except for Culicoides actoni Smith. The newly developed 3D-printed UV LED light trap demonstrated the following advantages over the commercial light trap: cost saving to obtain multiple units, ease of customization and standardization, and increased availability by end-users. Although further assessments in different environmental conditions are needed, this 3D-printed light trap design could minimize the constrains in vector surveillance programs worldwide.

Evaluation of disinfection performance of a multiple wavelength EBE-UV light source and comparison with UV-LEDs

Abstract: A new ultraviolet (UV) light source EBE-UV (electron beam excitation-UV) system was established in this study, which can emit UV light at four wavelengths (233/243/260/270 nm) simultaneously. The EBE-UV lamp emits deep ultraviolet light by electronically exciting the ultraviolet material YPO4:Pr3+. It has the advantage of being mercury-free and environmentally friendly, as well as higher photoelectric conversion efficiency. To evaluate the germicidal performance of the EBE-UV lamp, Gram-negative bacteria, Gram-positive bacteria, and fungi were selected for evaluation. The bactericidal efficiency of the EBE-UV lamp was tested and compared to the universal 255 nm and 275 nm UV-LEDs. As a result, the bactericidal effect of EBE-UV light was more effective than of single-wavelength UV-LEDs, especially against fungi. The level of Reactive Oxygen Species in the cells of the strain was increased to varying degrees by UV irradiation. There is a general weakening of energy metabolism, and DNA was damaged and fragmented. However, almost no significant cell membrane damage was found in this study. The EBE-UV light will show great potential due to its disinfection effect and device performance.

Evaluation of the chemical, cytological and bacteriological compositions of surgical smoke and evaluation of purification of smoke by ultraviolet light and various filters in laparoscopic surgeries

Abstract: Background: The present study aimed to assess the cytological, bacterial and chemical composition of laparoscopic surgical smoke and the evaluation of purification of surgical smoke by smoke purifying device containing ultraviolet (UV) light and various filters. Methods: Sixty patients undergoing laparoscopic abdominal surgery lasting >45 min were included in this randomized controlled study. The patients were divided into two groups: group A-smoke passing through smoke purifying device and group B-smoke without passing through smoke purifying device. Sample for cytological, bacteriological and chemical analysis were collected from both the groups. The primary outcome measures were to find the cytological, bacteriological and chemical composition of surgical smoke. The secondary outcome measure was evaluation of purification of surgical smoke by smoke purifying device containing ultraviolet light and various filters. Intergroup comparison of categorical and continuous variables was done using the Chi square test/Fisher’s exact test and unpaired t test respectively. Results: The present study shows the group A wherein smoke evacuating device containing various filters were used has no bacterial growth as well as no cells seen on cytological evaluation as compared to the group B wherein 21/30 (70.0%) cases had few lymphocytes and 3/30 (10.0%) cases had coagulase-negative Staphylococci wherein smoke evacuation device was not used. However, the chemical composition was comparable in both the groups. Conclusions: The smoke evacuation and filtration device, filtrates and clears the smoke of cells and bacteria as it passes through it.

Fluorescence of Oil Well Cuttings Under The Action of Ultraviolet Light As Pertaining To Depth of Wells Investigated

Abstract: In 1937, Lippert (6) published a survey of the radioactive properties of subterranean waters of Ellis County, Kansas. In 1940, Bell, Goodman, and Whitehead (1) reported a survey on the radioactivity of sedimentary rocks and associated petroleum. In 1944, w. L. Russell (10) reported on the total gamma ray activity of sedimentary rocks as indicated by Geiger-Mueller Counter determination. Lastly, in 1949, M. w. Johnston (5) made a survey of radioactivity of oilwell drilling fluid with depth of wells. Since Johnston's work cited above included only producing wells it was thought worthwhile to continue this investigation to include wells both in producing pools and in unproven territory. An additional new approach to this whole matter of geophysical prospecting for oil is to test oilwell cuttings for fluorescence since it is well known that particles from oil-bearing horizons do fluoresce under the action of ultraviolet light. While the fluorescence of oil under the action of ultraviolet light has been known for many years, the method of detecting the presence of oi l by means of the fluorescence of oilwell cuttings is not in general use among geologists at the present time, at least not in this region. Consequently it was decided to select six locations where drilling was contemplated, three in the Sutor Pool in Rooks County ; and, three new locations in unproven territory. The plan was to test the drilling fluids of each of these wells for radioactivity with depth using an LS64 scaling Geiger-Mueller Counter by El Tronics, 2 Incorporated; and, also to check the cuttings commencing at a depth of approximately 3000 feet, where the cuttings were first gathered, for a study of fluorescence when the cuttings are subjected to ultraviolet light.

COVID-19 and The Emergence of Industrial Grade Sanitization Applications Using Ultraviolet Light: The Case of Steribin LLC

Abstract: Knowledge regarding the power of ultraviolet light to kill various bacteria and viruses has existed for some time. Even prior to the onslaught of the COVID-19 virus, scientists were busy studying various types of UV light and how it might be applied to a wide variety of sanitization applications. Initially driven by the desire to effectively apply UV light to quickly sanitize airport security bins, Steribin was founded prior to the emergence of the COVID pandemic. It has since expanded into a number of sanitization applications, utilizing all of forms of UV technology, with a primary focus on sanitization needs in medicine and food processing.

New biosensors detect light deep inside the brain

Abstract: In recent years, the field of biosensors has seen significant advances in the development of fluorescent sensors, including quantum dots,1 upconversion nanoparticles,2 and fluorescent proteins,3 to monitor the generation of information in living systems. The fluorescence of these sensors can be observed by shining a laser at them. However, conventional fluorescent sensors are limited in their ability to image signals in deep tissues because most of the light is absorbed or scattered as it penetrates the tissue. To address this challenge, a team led by Jasanoff developed a novel sensor that converts light into a magnetic signal that is unaffected by absorption or scattering. This allows the response of the light detector to be visualized using magnetic resonance imaging (MRI; Figure 1).4 The development of this sensor has significant potential to improve our understanding of information processing in deep tissues. Schematic illustration of mapping light distribution in tissues using MRI-detectable photosensitive liposomes. To fabricate the photosensitive MRI probe, magnetic particles were encapsulated in light-responsive azobenzene-conjugated liposomes (called Light-LisNRs).5 By adjusting the composition and proportion of the lipid bilayer molecules, these liposome nanoparticles can switch from being permeable to being impenetrable, depending on the type of light exposure. This property allowed modulation of the MRI contrast of the Light-LisNRs and facilitated the optimization of the switchable longitudinal relaxation time (T1). Specifically, upon exposure to ultraviolet (UV) light, the Light-LisNRs became more permeable to water, resulting in a strong interaction between the magnetic particles and water and thereby producing strong MRI signals. Conversely, exposure to blue light caused the Light-LisNRs to become impermeable to water, resulting in the lack of a detectable MRI signal. The optimized Light-LisNRs could potentially be used to map light distribution in live animals. When these nanoparticles were injected into the living rat brain, they effectively diffused through the brain by convection, as evidenced by changes in the magnetic resonance signal. The probes exhibited exceptional light sensitivity, which could be demonstrated by changes in magnetic relaxation under blue and UV irradiation. Relative to the initial baseline, the probes showed significant differences in the mean MRI signals in response to UV and blue light, and the temporal characteristics of the light response observed during repeated photoperiods were consistent. The steady performance of Light-LisNRs in the rat brain suggests that they are suitable for the quantitative measurement of the light intensity distribution in tissues. In addition, the researchers used a hybrid model consisting of a beam spreading function combined with a homogeneous photon diffusion term to fit the experimental data and produced a quantitative map of the distribution of light emitted by the optical fiber implanted near the brain's striatum. These results highlight the potential of the optimized Light-LisNRs in mapping the distribution of light in living animals. In summary, this study describes the design of a novel sensor and its application elucidating light propagation in optically opaque environments. The sensor exploits the photomodulation of liposomal permeability to enhance the contrast produced by contrast agent molecules, leading to improved visualization in MRI. The results of this work demonstrate the potential of Light-LisNRs as a versatile tool for photon detection and highlight opportunities for further optimization through adjustments to action spectra, absorption cross sections, and contrast agent packaging parameters. The sensing approach outlined here holds promise for the future development of MRI probes capable of detecting stimuli beyond light, such as neurochemicals or other molecular species in the brain. In addition, the sensor may serve as a valuable tool for monitoring patients undergoing light-based therapies, including photodynamic therapy, which uses lasers to ablate cancer cells. Lei Luo: Conceptualization, Visualization, Writing - Original draft; Dandan Yang: Writing - Reviewing & Editing; Yu Yang: Conceptualization, Funding Acquisition, Writing - Reviewing & Editing. The authors declare no conflicts of interest.

UV light is not all bad for DNA

Abstract: Could the cellular mechanisms that cause sunburns help creating more stable therapeutics? Studying the effect of ultraviolet light on strands of DNA put together in various structures, we have discovered that gentle irradiation could protect the DNA from being degraded. This overcomes a major hurdle for translation into clinics without requiring extensive modifications.

Preparation and properties of NaLa(WO4)2:0.08Eu3+ phosphors

Abstract: Abstract In the environment of advocating low-carbon economy, the development of green lighting and the potential application of rare earth luminescent light sources have always attracted much attention. In this study, aiming at the existing defects of white LED, taking the new red rare earth phosphor excited by ultraviolet light as the research object, Eu3+ doped NaLa(WO4)2:0.08Eu3+ phosphors samples were prepared by microwave method. The prepared samples were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), fluorescence spectrum (PL), CIE color coordinates and other detection methods, and their phase composition, micro-morphology and luminescent properties were characterized. The results show that the doping of Eu3+ does not change the crystal structure of the matrix material, and the NaLa(WO4)2:0.08Eu3+ phosphors is micron-sized and irregular polyhedral at room temperature. It can be excited by ultraviolet light with wavelength of 395 nm to produce red light emission. The color coordinates of NaLa(WO4)2:0.08Eu3+ phosphors are (0.5794, 0.308), and the manufactured device can emit white light with color coordinates of (0.3060, 0.3307). Therefore, the NaLa(WO4)2:0.08Eu3+ red phosphors prepared in this study is expected to be used in the preparation of white LED devices.

Light-Powered Liquid Crystal Polymer Network Actuator Using TiO2 Nanoparticles as an Inorganic Ultraviolet-Light Absorber

Abstract: Recently, the design and fabrication of light-powered actuators have attracted immense attention because of the manufacturing of intelligent soft robots and innovative self-regulating devices. Accordingly, a liquid crystal polymer network (LCN) provides a promising platform due to its reversible and multistimulus-responsive shape-changing behaviors. In particular, doping nanoparticles with exclusive properties into the LCN can produce interesting results. In this work, we investigated a TiO2 nanoparticle-based LCN polymer light-powered actuator. TiO2 nanoparticles as an inorganic ultraviolet (UV)-light absorber can substantially affect the LCN polymer’s oscillatory behavior. Our results demonstrate that the oscillation characteristics are directly influenced by the presence of nanoparticles, and we studied the influencing factors. The effectiveness of the elastic modulus, thermomechanical force, and curvature was investigated using different weight percentages of TiO2 nanoparticles. Our results show that, in the presence of TiO2 nanoparticles, the polymer chain order and inter-chain interactions in the polymer matrix as well as the structural deformation of relevant polymer surfaces are changed.

Visible‐to‐UV Photon Upconversion: Recent Progress in New Materials and Applications

Abstract: Ultraviolet (UV, λ<400 nm) light is essential for various photochemical reactions, but its intensity in the solar spectrum is very low, and light sources that artificially generate high-energy UV light are inefficient and environmentally unfriendly. A solution to this problem is photon upconversion (UC) from visible (vis, λ>400 nm) light to UV light. Among several mechanisms, UC based on triplet-triplet annihilation (TTA-UC) in particular has made remarkable progress in recent years. The development of new chromophores has enabled highly efficient conversion of low-intensity visible light into UV light. In this review, we summarize the recent development of visible-to-UV TTA-UC, from the development of chromophores and their production into films to their application in various photochemical processes such as catalysis, bond activation and polymerization. Finally, challenges and opportunities in future material development and applications will be discussed.

Synthesis of Planar-Type ZnO Powder in Non-Nano Scale Dimension and Its Application in Ultraviolet Protection Cosmetics

Abstract: ZnO is one of the most widely used inorganic sunscreens, owing to its fine particle size and UV light shielding capability. However, powders at nanosizes can be toxic and cause adverse effects. The development of non-nanosized particles has been slow. The present work investigated synthesis methods of non-nanosized ZnO particles for ultraviolet protection application. By altering the starting material, KOH concentration, and input speed, the ZnO particles can be obtained in different forms, including needle type, planar type, and vertical wall type. Cosmetic samples were made by mixing different ratios of synthesized powders. The physical properties and the UV blockage efficacy of different samples were evaluated using scanning electron microscopy (SEM), X-ray diffraction (XRD), particle size analyzer (PSA), and ultraviolet/visible (UV/Vis) spectrometer. The samples with 1:1 ratio of needle-type ZnO and vertical wall-type ZnO exhibited superior light blocking effect owing to improved dispersibility and prevention of particle agglomeration. The 1:1 mixed sample also complied with the European nanomaterials regulation due to the absence of nanosized particles. With superior UV protection in the UVA and UVB regions, the 1:1 mixed powder showed potential to be used as a main ingredient in UV protection cosmetics.