Min Of Ultraviolet Irradiation Research Articles

ECM-based bioadhesive hydrogel for sutureless repair of deep anterior corneal defects.

Corneal transplantation is the gold standard treatment for corneal-related blindness; however, this strategy faces challenges such as limited donor cornea, graft rejection, suture-related complications, and the need for specialized equipment and advanced surgical skills. Development of tissue adhesives for corneal regeneration is of great clinical value. However, currently available corneal tissue sealants pose challenges, such as lack of safety, biocompatibility, and desired mechanical properties. To meet these requirements simultaneously, a bovine stromal corneal extracellular matrix (dCor) was used to design a bioadhesive photocurable hydrogel based on gelatin methacrylate (GelMA) and polyethylene glycol diacrylate (PEGDA) hydrogels (dCor/Gel-PEG). Integration of dCor into the dual networks of GelMA and PEGDA (Gel-PEG) led to a bioadhesive hydrogel for curing corneal defects, which could be crosslinked by Irgacure 2959 within 5 min ultraviolet irradiation. The viability of corneal stromal stem cells (CSSCs) was improved on the dCor/Gel-PEG hydrogel in comparison to the Gel-PEG hydrogel. The gene expression profile supported the keratocyte differentiation of CSSCs seeded on dCor/Gel-PEG via increased KERA and ALDH, with inhibited myofibroblast transdifferentiation via decreased α-SMA due to the presence of dCor. Interestingly, the dCor/Gel-PEG hydrogel exhibited favorable mechanical performance in terms of elasticity and bioadherence to the host corneal stroma. Ex vivo and in vivo examinations proved the feasibility of this hydrogel for the sutureless reconstruction of deep anterior corneal defects with promising histopathological results.

On-demand delivery of therapeutic extracellular vesicles by encapsulating in monodispersed photodegradable hydrogel microparticles using a droplet microfluidic device

Mesenchymal stem cells (MSCs)-derived extracellular vesicles (EVs) have been studied for therapeutic applications due to easier endocytosis and fewer adverse effects than MSCs. However, EVs injected medicinally are diluted by body fluids and inefficiently delivered to the therapeutic target, limiting original therapeutic effects. Therefore, biocompatible carriers such as hydrogels are needed in EVs delivery systems to enhance EVs retention and release EVs sustainably at therapeutic targets. In addition to the advantages of delivering EVs using hydrogels, photodegradable hydrogels provide a controllable degradation process via ultraviolet (UV) irradiation. However, long-term UV irradiation to degrade the photodegradable hydrogel may potentially damage EVs and targets; therefore, a carrier that can be degraded with shorter UV irradiation is required. Herein, we generate photodegradable hydrogel microparticles (PHMPs) that can release encapsulated EVs sustainably within 2 min of UV irradiation by droplet-based microfluidics. By regulating the fluidic resistance of the channels, monodisperse PHMPs, which can avoid undesired variations in EVs release kinetics, were generated. EVs were successfully retained in PHMPs in the absence of external stimuli, and EVs were released from PHMPs and enhanced cell proliferation following UV irradiation. Therefore, PHMPs can overcome the limitations of conventional EVs delivery, including their inability to deliver EVs sustainably and on-demand, and low EVs retention.

Effect of modified ZnO nanoparticles synthesized via the sonochemical method on the self-cleaning behavior of a waterborne acrylic coating

In this research, the self-cleaning property of Al-doped ZnO nanoparticles prepared via the sonochemical method was investigated. The photocatalytic and hydrophilic activities of nanoparticles were studied while being applied as an additive into the waterborne acrylic resin-based coating. The influence of various doping amounts of Al with ZnO has been evaluated in terms of crystallographic structures, morphologies, optical properties, etc. using XRD, TEM, EDS, and UV–Vis analysis. Hexagonal and rod-like nanoparticles were revealed as the dominant morphology for the low and high dosage of doped Al, respectively. The photocatalytic activity of coating was studied using methyl orange by exposing them to ultraviolet (UV) irradiation. Results showed that acrylic coating with doped nanoparticles represented higher degradation, in comparison with the pure ZnO nanoparticles. The rate of degradation of 5% Al-doped nanoparticles was found to be higher than that of other samples. Furthermore, the hydrophilic property of the coating was determined by measuring the water droplet contact angle with the surface under UV irradiation. The results showed that the resin coating with doped nanoparticles represented a lower contact angle, compared to the pure ZnO nanoparticles. The least angle equal to 21° was achieved at 7% Al-doped sample after 180 min UV irradiation. Kinetic studies showed that the degradation of methyl orange corresponds well with the first-order reaction.

Rational modification in the photochromic and self-bleaching performance of hierarchical microsphere Cu@h-WO3/WO3·nH2O composites

Herein, we used a self-assembly method to synthesize novel Cu@h-WO3/WO3·nH2O hierarchical microsphere composites with enhanced photochromism and self-bleaching performance. The composite fabricated with 1.0% Cu-WO displayed a rapid change from light-yellow to dark-gray after 2 min of ultraviolet irradiation and self-bleached in less than 1 h in the dark. Composite samples were characterized to investigate changes in their morphology and structure after being doped with different amounts of Cu. The hierarchical microspheres were composed of small, well-dispersed nanorods that provided active sites capable of absorbing light. Ensuring the proper Cu content in the WO3 lattice promoted the separation of carriers through interfacial charge transfer (IFCT) and prevented the recombination of electron-hole pairs due to excessive doping. Combing hexagonal WO3 with WO3·nH2O and Cu provided unobstructed channels, proton sources, and interactions with W species, which improved the efficiency of proton insertion and extraction. The WO3 hybrid materials described in this research displayed high coloration efficiencies and reversibility and may find applications in solar energy devices.

UV-Stable and Highly Efficient Perovskite Solar Cells by Employing Wide Band gap NaTaO3 as an Electron-Transporting Layer.

Organic-inorganic halide perovskite solar cells (PSCs) still suffer from stability issues which are caused by possible erosions from moisture, ultraviolet (UV) light, heat, and so forth. An electron-transporting layer (ETL), that is, TiO2, is a key component for state-of-the-art PSCs. However, UV-caused desorption of O2- in TiO2 would accelerate the degradation of PSCs. Herein, we explored perovskite oxide, NaTaO3, for the first time as an alternative ETL in PSCs. NaTaO3 as an ETL can effectively avoid the damage from UV irradiation, inhibit the degradation of the perovskite layer, and improve the overall stability of the PSC. PSCs fabricated with NaTaO3 yielded a power conversion efficiency (PCE) of 21.07% with a retention of more than 80% of this initial PCE after 240 min UV irradiation in air while the reference device with a PCE of 20.16% can only retain about 53% of its initial PCE after the same testing condition. The developed stable perovskite oxide material of NaTaO3 provides the diversification of electron-selective contact for highly efficient and stable PSCs.

Biotemplated synthesis of Ag-ZnO nanoparticles/bacterial cellulose nanocomposites for photocatalysis application

ABSTRACT Bacterial cellulose (BC) was used as a biotemplate for facile fabrication of silver-zinc oxide nanoparticles/bacteria cellulose (Ag-ZnO/BC) nanocomposite having high potential application in photocatalysis via a one-step method. Scanning electron microscopy images confirmed that BC nanofibers were uniformly coated with Ag-ZnO in aqueous suspension using co-precipitation method. The size of Ag-ZnO nanoparticle in BC and its photodegradability were increased with the increasing concentration of AgNO3 added. The greatest efficiency is demonstrated by the ability of this material to degrade methylene blue (MB) by up to 76% after a 180 min ultraviolet irradiation period, indicated that the Ag-ZnO/BC nanocomposite is a promising candidate as robust ultraviolet responsive photocatalyst.

Induction of Anthocyanin Accumulation in Callus Culture of 'Karaerik' (Vitis vinifera L.) by Ultraviolet Irradiation Effect

In this study, the effect of ultraviolet (UV) irradiation on the induction of anthocyanin production in calluscultures of 'Karaerik' grape cultivar was investigated. The most appropriate callus tissues were obtained from the leaves ofthe cuttings grown in in vitro plants. Gamborg B-5 medium containing 3 combinations of NAA (naphthalene acetic acid),and Kin (kinetin) was used. Callus tissues were subcultured two times with 21 days intervals. After the second subculture,12 and 15 day old callus tissues were exposed to 254 nm UV-C light at 10 cm distance from the source for 10 and 15 min byopening covers of the petri dishes in the sterile cabin. After the treatment, callus tissues were incubated under darkconditions. Anthocyanin values were measured at 0, 24th, 48th and 72nd hours by spectrophotometer. It has been determinedthat UV radiation is effective for the induction of anthocyanin production in grape tissues. The highest anthocyaninproduction (196.74 μmol g-1 FW) was obtained from 12 day old calli grown in the first medium for a 72-hour incubationperiod after 10 min UV irradiation.

Preparation and properties of ultraviolet/thermal dual-curable polyurethane acrylate

Ultraviolet (UV)/thermal dual-curable polyurethane acrylate (PUA) mixtures were prepared using a PUA oligomer, tripropylene glycol diacrylate (TPGDA), benzoyl peroxide (BPO), 2,4,6-trimethylbenzoyldiphenyl phosphine oxide (TPO), and cobalt isooctanoate. For purposes of comparison, a UV-curable PUA mixture was prepared by mixing the PUA oligomer, TPGDA, and TPO. When placed under a UV lamp (400 W, 50 mW/cm2), the surface drying time of each curable mixture was approximately 2 s. The content of volatiles during UV curing (the intensity of the lamp was 100 mW/cm2) was less than 0.3 wt%, and the content of potential volatiles (the test condition was heating at 110 °C for 1 h after UV curing) was below 1.0 wt%. Compared with the UV-cured sample, the UV/thermal dual-cured sample containing cobalt isooctanoate had more favorable properties, that is: (1) better acid and alkali resistance; and (2) better thermal stability and higher gel content. The temperature at 5 wt% weight loss (T5wt.%) and the gel fraction of the UV-cured sample (the curing condition was 1 min of UV irradiation) were 269.4 °C and 94.6%, respectively. The T5wt.% and the gel fraction of the UV/thermal dual-cured sample (cured at 100 °C for 10 min after 1 min of UV irradiation) were 318.2 °C and 99.8%, respectively. BPO and cobalt isooctanoate had little effect on the surface drying rate of the curable mixtures, and the performance of the cured samples was improved by thermal treatment following irradiation with UV. Considering the dyeing effect of BPO, this system provides a more practical approach to the complete curing of colored UV-curable resins.

Metal oxides and ultraviolet light-based photocatalytic pretreatment of biomass for biogas production and lignin oxidation

Lignocellulosics are abundant and readily available as the raw material for the production of biogas. However, the structure of this raw material needs to be modified to increase its digestibility during anaerobic fermentation. Various pretreatment methods that have been proposed in the past have been examined; however, the focus of the present study was to pretreat a wheat straw (WS) substrate using an advanced oxidation process (AOP) with a metal oxide photocatalyst combined with ultraviolet (UV) irradiation. Four different metal oxides were examined at 0, 1, 2, 3, and 4% dosages (w/w) coupled with UV irradiation for 0, 60, 120, and 180 min. Experimental results revealed that among all metal oxide catalysts examined, only the 4% CuO combined with 180 min UV irradiation caused the most lignin to be released from the WS. This resulted in the highest vanillic acid (VA) being produced (4.32 ± 0.15 mg VA/g VS). This WS pretreatment also resulted in a biomethane potential (BMP) assay of 384 ± 16 NmL CH4/g VS. The BMP assay results revealed a maximum 28% increase in biodegradability and a 57% increase in methane production. The use of either metal oxide catalysts or UV irradiation alone resulted in ineffective WS pretreatment.

Magnetic TiO2/NiFe2O4/reduced graphene oxide nanocomposite as a recyclable photocatalyst for photocatalytic removal of methylene blue under visible light

In this research, ternary magnetic TiO2/NiFe2O4/reduced graphene oxide (TiO2/NiFe2O4/rGO) nanocomposites with different amounts of graphene were synthesized using the hydrolysis method, and their photocatalytic activity was measured by degradation of methylene blue (MB) under visible light and ultraviolet (UV) irradiation. The characteristics of the samples were analyzed using FESEM/EDX, TEM, XRD, FTIR, DRS, and N2 adsorption-desorption methods. The XRD and FESEM analyses indicated that rGO surface was covered by TiO2 and NiFe2O4 nanoparticles (NPs). According to the photocatalytic degradation tests, TiO2/NiFe2O4/rGO with the highest amount of graphene (0.120 g) exhibited good photocatalytic performance and could be easily recycled by applying an external magnetic field due to presence of NiFe2O4 NPs. We obtained 71% and 87% MB degradation under 90 min visible light and UV irradiation, respectively, in the presence of TiO2/NiFe2O4/rGO containing 0.120 g of graphene. Furthermore, we observed just a slight decline in the performance of the synthesized ternary nanocomposite containing 0.120 g of graphene after four cycles.

Influence of ultraviolet irradiation treatment on porcelain bond strength of titanium surfaces.

To determine the effect of titanium (Ti) surface modification by ultraviolet irradiation (UVI) on the bond strength between Ti and porcelain. Grade 2 Ti plates were allotted to five groups: sandblasted (SA), 15 min UVI (UV), SA+5 min UVI (SA+UV5), SA+10 min UVI (SA+UV10), and SA+15 min UVI (SA+UV15). After surface treatment, porcelain was added. A precious metal (MC) was used for comparison with Ti. The effects of 24-h storage at room temperature versus thermal cycling only at 5 and 55°C in water were evaluated. Subsequently, the tensile strength of each sample was tested. Data were analyzed using one-way analysis of variance and the Tukey test. In both the room temperature and thermal cycling groups, the MC and SA+15 min UVI samples showed significantly greater bond strengths than the other samples (p<0.05). UVI processing efficiently increases the bond strength between porcelain and the Ti surface.

Photocatalytic hydrogen peroxide bleaching of cotton

In this study, photocatalytic bleaching of cotton via ultraviolet (UV) and hydrogen peroxide (H2O2) has been investigated. 254 nm UV light was used for this purpose and the UV irradiation intensity was measured. A specially designed UV cabinet with UV lamps on both sides and top of the cabinet with total 18 UV lamps creating 470 Watts was used during the experiments. The whiteness degrees of the cotton samples that were bleached by the H2O2/UV treatment were compared to the whiteness degrees of the conventionally bleached (pad-steam method) cotton fabric samples. Satisfactory whiteness degrees could be obtained by H2O2/UV treatment for 40 and 60 min treatment times. However, strength loss was high for 60 min UV irradiation. The UV irradiation intensity was also found to be effective on the whiteness and strength values of the samples.

Synthesis and characterization of Pb2SiO4 nanostructure: study of photo-catalytic behavior of reactive Red198 and reactive Orange16 dyes as pollutants

Pure Pb2SiO4 nanostructures were fabricated using amines as alkaline agents by sol–gel method and characterized via X-ray powder diffraction (XRD), Fourier-transformed infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDS). The average crystallite size of the products in presence and absence of the alkaline agent in the reaction was calculated about 18 and 34 nm by XRD technique, respectively. The type of alkaline agent was evaluated to achieve the optimized nanostructure. The results showed that the ethylenediamine as an alkaline agent has a better performance than the other alkaline agents (ammonia, triethylenetetramine, and tetraethylenepentamine). Optical property of optimized nanostructure was studied by diffuse reflectance spectroscopy (DRS) and its band gap was estimated to about 3.3 eV. It is the first time that photo-catalytic behavior of Pb2SiO4 nanostructure was investigated. The photo-catalytic performance of optimized Pb2SiO4 nanostructure was evaluated in the presence of various concentrations of Reactive Red198 and Reactive Orange16 dyes. The degradation percentage of dyes in various concentrations (5, 7, and 9 ppm) was obtained for Reactive Red198 and Reactive Orange16 about 100, 57, and 52% and also 100, 52, and 42% after 75 min ultraviolet irradiation, respectively. At 5 ppm concentration, Reactive Orange16 pollutant destruction was faster than Reactive Red198.

Photolysis and UV/H 2 O 2 of diclofenac, sulfamethoxazole, carbamazepine, and trimethoprim: Identification of their major degradation products by ESI–LC–MS and assessment of the toxicity of reaction mixtures

Abstract The photolysis of diclofenac (DCF), sulfamethoxazole (SMX), carbamazepine (CBZ), and trimethoprim (TMP) was investigated using a low-pressure (LP) mercury ultraviolet (UV) lamp (254 nm) and a combination of UV with hydrogen peroxide (H 2 O 2 ). For each experiment, 5 mg/L of each pharmaceutical was prepared in pure water and individually degraded by either UV alone or UV/H 2 O 2 . DCF and SMX were highly susceptible to UV treatment and completely degraded to below their LC–MS detection limit (1 μg/L) after only 8 min of UV irradiation. TMP and CBZ were more resistant to UV treatment, with only 58.2 and 25.2% degradation (after 1 h UV exposure). The combination of H 2 O 2 addition (up to 0.2 g/L) with UV significantly improved the removal rate of TMP and CBZ up to 91.2 and 99.7% of the initial concentration, respectively. A number of novel transformation compounds were identified as UV or UV/H 2 O 2 degradation products using LC–MS. The range and amount of these transformation compounds strongly depended on the applied treatment conditions. The toxicity of each pharmaceutical solution before and after treatment was also evaluated and all parent compounds were non-toxic at the tested concentration (i.e. 5 mg/L). DCF, in particular, but also CBZ and SMX, showed an increase in solution toxicity after treatment with UV only, indicating the presence of photolytic degradation products that are more toxic than the parent compounds. Treatment with UV/H 2 O 2 reduced the toxicity of all solutions to below the detection limit of the assay.

Investigation of single nucleotide polymorphism loci susceptible to degradation by ultraviolet light

DNA in biological fluids is often degraded by environmental factors. Given that single nucleotide polymorphism (SNP) analyses require shorter amplicons than short tandem repeat (STR) analyses do, their use in human identification using degraded samples has recently attracted attention. Although various SNP loci are used to analyze degraded samples, it is unclear which ones are more appropriate. To characterize and identify SNP loci that are susceptible or resistant to degradation, we artificially degraded DNA, obtained from buccal swabs from 11 volunteers, by exposure to ultraviolet (UV) light for different durations (254 nm for 5, 15, 30, 60, or 120 min) and analyzed the resulting SNP loci. DNA degradation was assessed using gel electrophoresis, STR, and SNP profiling. DNA fragmentation occurred within 5 min of UV irradiation, and successful STR and SNP profiling decreased with increasing duration. However, 73% of SNP loci were still detected correctly in DNA samples irradiated for 120 min, a dose that rendered STR loci undetectable. The unsuccessful SNP typing and the base call failure of nucleotides neighboring the SNPs were traced to rs1031825, and we found that this SNP was susceptible to UV light. When comparing the detection efficiencies of STR and SNP loci, SNP typing was more successful than STR typing, making it effective when using degraded DNA. However, it is important to use rs1031825 with caution when interpreting SNP analyses of degraded DNA.

Effect and mechanism of a High Gradient Magnetic Separation (HGMS) and Ultraviolet (UV) composite process on the inactivation of microbes in ballast water

The patented technology of a High Gradient Magnetic Separation (HGMS)-Ultraviolet (UV) composite process was used to treat ballast water. Staphylococcus aureus (S. aureus) was selected as the reference bacteria. After treatment by the HGMS-UV process, the concentration of S. aureus on the log 10 scale was lower than 2 at different flow rates, S. aureus suffered the most serious damage, and K+ leakage of the bacteria was 1.73mg/L higher than separate 60min UV irradiation (1.17mg/L) and HGMS (0.12mg/L) processes. These results demonstrated that the HGMS-UV composite process was an effective approach to treat ballast water. Further, the HGMS process had synergistic action on the subsequent UV irradiation process and accelerated cell membrane damage. Meanwhile, the results of superoxide dismutase (SOD) activities of bacteria and DNA band analyses indicated that the inactivation mechanisms were different for HGMS and UV irradiation.

Production of trans-resveratrol in "Cabernet Sauvignon" (Vitis Vinifera L.) callus culture in response to ultraviolet-C irradiation

In this study, the effects of ultraviolet (UV) irradiation time, incubation time and callus age were investigated for the induction of trans -resveratrol production in callus cultures of Vitis vinifera L. 'Cabernet Sauvignon'. Callus tissues were exposed to 254 nm UV light at 10 cm distance from the source for 10 and 15 min by opening covers of the petri dishes in sterile cabin. High Pressure Liquid Chromatography (HPLC) was used for the determination of trans -resveratrol production and concentrations were recorded at 0, 24, 48 and 72 hours after beginning of incubation. Separation by HPLC was achieved using a C18 column and a gradient elution with acetonitrile and water (from 10 to 85 % acetonitrile). The peak of trans -resveratrol was detected at 330 nm and identified from the retention time (12.5 min) trans-resveratrol standard. Determination coefficient for linearity (R 2 ), Limit of Detections (LOD), Limit of Quantification (LOQ) and relative standard deviation (RSD) values of the method were found as 0.9994, 0.12, 0.35 and 1.9, respectively. The highest trans -resveratrol concentration (62.66 μg·g-1 callus fresh weight) was determined in 48 hours of 12 days-old callus cultures irradiated for 10 minutes. Both 10 min and 15 min UV irradiation periods were found to be effective for the induction of trans -resveratrol production and thus callus cultures could be convenient for trans -resveratrol production.

꼬마선충의 coelomocyte 세포가 스트레스 저항성 및 번식력에 미치는 영향

체강 소체는 꼬마 선충에서 내화과정을 통해 체강 내 액체를 세포 안으로 들여오는 특이적인 세포이다. 본 연구실에서의 최근 연구 결과에 의하면, 꼬마 선충에서 식이제한에 의한 수명연장에 체강 소체가 필수적임이 발견되었다. 본 연구에서는 꼬마 선충에서 체강 소체를 제거하였을 경우, 환경적 스트레스에 대한 저항성과 번식력을 개체 수준에서 연구하였다. 체강 소체는 체강 소체에만 특이적으로 발현하는 디프테리아 독소를 이용하여 제거하였다. 먼저 자외선에 대한 저항성은 20 J/cm²/min의 자외선을 조사한 후, 생존률의 변화를 매일 기록하였다. 또한 꼬마 선충을 35&#x2103; 배양기에 10시간 동안 배양하여 열 스트레스를 가한 후, 생존률의 변화를 관찰하였다. 산화성 스트레스는 paraquat를 이용하여 생체 내 산화성 스트레스를 유도한 다음, 산화성 스트레스에 대한 저항성을 비교하다. 번식력의 경우, 번식기간 동안의 총 자손의 수와 날짜 별 자손의 수를 비교 분석하였다. 그 결과, 체강소체는 개체의 자외선 스트레스의 저항성에는 필수적이지만, 열과 산화성 스트레스 저항성에는 영향을 미치진 않는 것으로 보인다. 그리고 개체의 번식력에도 관여하는 것으로 나타났다. 본 연구 결과는 노화 및 식이제한에 의한 수명연장의 기전을 이해하는데 기여할 것으로 사료된다. Coelomocytes are specialized cells that continually and nonspecifically scavenge fluid from the body cavity through endocytosis in Caenorhabditis elegans. Our previous study revealed that coelmocytes were specifically required for dietary-restriction-induced longevity in C. elegans. In the present study, we examined the effect of coelomocyte ablation on the response to environmental stressors and reproduction in C. elegans. Coelomocytes were ablated using diphtheria toxin specifically expressed in coelomocytes. After exposing worms to 20 J/cm²/min of ultraviolet irradiation in vivo, the survival of the worms was monitored daily. To examine their response to heat stress, their survival after 10 h of 35&#x2103; heat shock was measured. Oxidative stress was induced using paraquat, and the susceptibility to oxidative stress was compared between wild-type control and coelomocyte-ablated worms. The total number of progeny produced was counted, and the time-course distribution of the progeny was determined. The worms with ablated coelomocytes showed reduced resistance to ultraviolet irradiation, but the ablation of coelomocytes had no effect on their response to heat or oxidative stress. The number of progeny produced during the gravid period was significantly decreased in the coelomocyte-ablated worms. These findings suggest that coelomocytes specifically modulate the response to ultraviolet irradiation and are required for normal reproduction in C. elegans. The findings could contribute to understanding of the mechanisms underlying dietary-restriction-induced longevity.

The potential use of annealed high-albite (AlSi3O8Na) as an ultraviolet radiation dosimeter

The potential use of annealed high-albite (AlSi3O8Na) as an ultraviolet radiation dosimeter

The effect of ultraviolet irradiation, heat, pH, ozone, salinity and chemical disinfectants on the infectivity of white spot syndrome baculovirus

The virucidal effects of ultraviolet (UV) irradiation, heat, pH, ozone, salinity and some chemical disinfectants on white spot syndrome baculovirus (WSBV) were investigated by infectivity assay using juvenile black tiger prawn, Penaeus monodon. WSBV became completely non-infectious after 60 min UV irradiation (9×10 5 μW s/cm 2). WSBV was rendered non-infectious by 55°C and 70°C heat treatment within 90 min and 5 min, respectively. WSBV was also completely inactivated by high acidity, pH 1 for 10 min, pH 3 for 1 h and by high alkalinity, pH 12 for 10 min at RT (25°C). The effective concentration for ozone to reduce WSBVs infectivity to zero was 0.5 μg/ml as a total residual oxidant for 10 min at RT. WSBV was inactivated by contact for 10 min at RT with a final concentration of 100 ppm of sodium hypochlorite and povidone iodine and 75 ppm of benzalkonium chloride. Sodium chloride in concentrations ranging from 0–10% had no virucidal effect on the infectivity of WSBV.