Adding Hydrogen Peroxide Research Articles

Characterization of Carboxylated Cellulose Nanocrytals Isolated through Catalyst-Assisted H2O2 Oxidation in a One-Step Procedure.

A green and facile method was designed to isolate a type of cellulose nanocrystal (CNC) with carboxylated surfaces from native cellulose materials. Because isolation and modification processes of cellulosic particles are generally performed separately using harmful chemicals and multiple steps, the one-pot approach employed in this work is interesting from both an economical and ecological point of view. The reaction is carried out by adding hydrogen peroxide as an oxidant and copper(II) sulfate as a catalyst in acidic medium under mild thermal conditions. The charge content of the carboxylated CNC is about 1.0 mmol g-1, measured by a conductometric titration. Fourier transform infrared spectroscopy also proved the presence of carboxyl groups on the CNC particles. Atomic force microscopy along with optical polarized microscopy readily showed a rod shape morphology for the cellulosic particles. An average length of 263 nm and width of 23 nm were estimated by transmission electron microscopy. Dynamic laser scattering on carboxylated CNC suspensions by adding salt confirmed that nanoparticles are electrostatically stable. Carboxylated CNCs were furthermore characterized by solid carbon-13 nuclear magnetic resonance and X-ray spectroscopy.

Catalytic oxidation of phenol waste waters by hydrogen peroxide with the help of step-type regulation by redox-potential

The change in redox-potential (Eh) and active reaction (pH) was studied under the catalytic oxidation of phenols by hydrogen peroxide in waste waters from the production of canning tin. In the capacity of a catalyzer were used tin ions present in waste water. After adding hydrogen peroxide Eh of waste water increased to +(550-580) mV. During the process of phenols oxidation Eh decreased to the value +(300-500) mV, and pH decreased from 6,2-6,3 to 1,1-1,6. This resulted in phenol oxidation to the required value of 0,2 mg/l. In decreasing Eh to +(130-150) mV the residual concentration of phenols constitutes only 1,25-1,90 mg/l. In the process of reaction the temperature of waste water increased to (44-48) 0 C. The increase of the starting dosage of hydrogen peroxide led to the decrease of pH below 1,1-1,0 and to the increased temperature of waste water to (60-70) 0 C and higher. Because of this the decomposition takes place of hydrogen peroxide with the emission of oxygen in the form of vigorous boiling of waste water in the mixer-reactor and the hindering of the process of phenol oxidation. For keeping optimum parameters of oxidation under conditions of changing the concentration of admixtures the step-type increase of redox-potential by hydrogen peroxide up to +(550-600) mV is proposed with supporting the value of pH by alkali in optimal limits from 5,5-6,0 to 2,4-2,6. The process of dosing reagents is implemented in a non-flowing mechanical mixer-reactor. The algorithm is presented of four-step dosing reagents in industrial conditions which is carried out in automatic regime. The automated step-type regulation of Eh and pH is perspective for treating waste waters from toxic admixtures with oxidation-reduction properties.

New Insights on the Photodegradation of Caffeine in the Presence of Bio-Based Substances-Magnetic Iron Oxide Hybrid Nanomaterials.

The exploitation of organic waste as a source of bio-based substances to be used in environmental applications is gaining increasing interest. In the present research, compost-derived bio-based substances (BBS-Cs) were used to prepare hybrid magnetic nanoparticles (HMNPs) to be tested as an auxiliary in advanced oxidation processes. Hybrid magnetic nanoparticles can be indeed recovered at the end of the treatment and re-used in further water purification cycles. The research aimed to give new insights on the photodegradation of caffeine, chosen as marker of anthropogenic pollution in natural waters, and representative of the contaminants of emerging concern (CECs). Hybrid magnetic nanoparticles were synthetized starting from Fe(II) and Fe(III) salts and BBS-C aqueous solution, in alkali medium, via co-precipitation. Hybrid magnetic nanoparticles were characterized via X-ray diffraction (XRD), thermo-gravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. The effect of pH, added hydrogen peroxide, and dissolved oxygen on caffeine photodegradation in the presence of HMNPs was assessed. The results allow for the hypothesis that caffeine abatement can be obtained in the presence of HMNPs and hydrogen peroxide through a heterogeneous photo-Fenton mechanism. The role of hydroxyl radicals in the process was assessed examining the effect of a selective hydroxyl radical scavenger on the caffeine degradation kinetic.

Improved removal of blood contamination from ThinPrep cervical cytology samples for Raman spectroscopic analysis.

There is an unmet need for methods to help in the early detection of cervical precancer. Optical spectroscopy-based techniques, such as Raman spectroscopy, have shown great potential for diagnosis of different cancers, including cervical cancer. However, relatively few studies have been carried out on liquid-based cytology (LBC) pap test specimens and confounding factors, such as blood contamination, have been identified. Previous work reported a method to remove blood contamination before Raman spectroscopy by pretreatment of the slides with hydrogen peroxide. The aim of the present study was to extend this work to excessively bloody samples to see if these could be rendered suitable for Raman spectroscopy. LBC ThinPrep specimens were treated by adding hydrogen peroxide directly to the vial before slide preparation. Good quality Raman spectra were recorded from negative and high grade (HG) cytology samples with no blood contamination and with heavy blood contamination. Good classification between negative and HG cytology could be achieved for samples with no blood contamination (sensitivity 92%, specificity 93%) and heavy blood contamination (sensitivity 89%, specificity 88%) with poorer classification when samples were combined (sensitivity 82%, specificity 87%). This study demonstrates for the first time the improved potential of Raman spectroscopy for analysis of ThinPrep specimens regardless of blood contamination.

Characterisation of peroxidasin activity in isolated extracellular matrix and direct detection of hypobromous acid formation

Peroxidasin is a heme peroxidase that catalyses the oxidation of bromide by hydrogen peroxide to form an essential sulfilimine cross-link between methionine and hydroxylysine residues in collagen IV. We investigated cross-linking by peroxidasin embedded in extracellular matrix isolated from cultured epithelial cells and its sensitivity to alternative substrates and peroxidase inhibitors. Peroxidasin showed peroxidase activity as measured with hydrogen peroxide and Amplex red. Using a specific mass spectrometry assay that measures NADH bromohydrin, we showed definitively that the enzyme releases hypobromous acid (HOBr). Less than 1 μM of the added hydrogen peroxide was used by peroxidasin. The remainder was consumed by catalase activity that was associated with the matrix. Results from NADH bromohydrin measurements indicates that low micromolar HOBr generated by peroxidasin was sufficient for maximum sulfilimine cross-linking, whereas 100 μM reagent HOBr or taurine bromamine was less efficient. This implies selectivity for the enzymatic process. Physiological concentrations of thiocyanate and urate partially inhibited cross-link formation. 4-Aminobenzoic acid hydrazide, a commonly used myeloperoxidase inhibitor, also inhibited peroxidasin, whereas acetaminophen and a 2-thioxanthine were much less effective. In conclusion, HOBr is produced by peroxidasin in the extracellular matrix. It appears to be directed at the site of collagen IV sulfilimine formation but the released HOBr may also undergo other reactions.

Different Precipitant Preparation of Nickel-Doped Mn/TiO<sub>2</sub> Catalysts for Low-Temperature SCR of NO with NH<sub>3</sub>

The Mn-Ni/TiO2 catalyst was prepared by co-precipitation method and investigated for the low-temperature selective catalytic reduction (SCR) of NO with NH3 in this work, and Mn-Ni/TiO2 catalysts were prepared by different precipitants respectively such as sodium hydroxide, carbamide, ammonia or hydrogen peroxide. The microstructure and performance of catalysts were investigated. The activitiesof catalysts prepared by different precipitants were studied in the temperature range 90°C-350°C. The results show that Mn-Ni/TiO2catalyst prepared by CO(NH2)2-NH3·H2O-H2O2 compound precipitant has an extraordinary performance even at the low temperature of 120°C. H2-TPR results show the peak positions shift to lower temperatures, standing for the reduction potential of MnOx species is increased compared to those of Mn/TiO2 catalysts. The interaction of Ni and Mn atoms is beneficial to an enhancement of the oxygen mobility due to CO(NH2)2-NH3·H2O-H2O2 as precipitant. It is worth noting that the low temperature peak area increased by adding hydrogen peroxide as precipitant. NH3-TPD results illustrat that for the Mn/TiO2 and Mn-Ni/TiO2 catalysts which are attributed to NH3 desorbed by weak acid sites and Brønsted acid sites.

A Catalytic Conversion: Westcom Showcases Her Science Talents

Twenty-three-year-old Alayna Westcom stood onstage in a white dress with a blue atom emblem, blue shoes, and lab glasses. On a table covered by a white tablecloth, she added hydrogen peroxide and potassium iodide to a little soap and then stepped back to watch. "Don't try this at home," she teased as white foam erupted onto the stage. It was a catalytic decomposition reaction that goes by the nickname "elephant's toothpaste." The hydrogen peroxide rapidly decomposes into water and oxygen gas, and when the gas gets trapped in the soap, voilá-bubbles, and a huge shot of foam.

Hydrogen peroxide kinetics in water radiolysis

The kinetics of the formation and reaction of hydrogen peroxide in the long time γ- radiolysis of water is examined using a combination of experiment with model calculations. Escape yields of hydrogen peroxide on the microsecond time scale are easily measured with added radical scavengers even with substantial amounts of initial added hydrogen peroxide. The γ-radiolysis of aqueous hydrogen peroxide solutions without added radical scavengers reach a steady state limiting concentration of hydrogen peroxide with increasing dose, and that limit is directly proportional to the initial concentration of added hydrogen peroxide. The dose necessary to reach that limiting hydrogen peroxide concentration is also proportional to the initial concentration, but dose rate has a very small effect. The addition of molecular hydrogen to aqueous solutions of hydrogen peroxide leads to a decrease in the high dose limiting hydrogen peroxide concentration that is linear with the initial hydrogen concentration, but the amount of decrease is not stoichiometric. Proton irradiations of solutions with added hydrogen peroxide and hydrogen are more difficult to predict because of the decreased yields of radicals; however, with a substantial increase in dose rate there is a sufficient decrease in radical yields that hydrogen addition has little effect on hydrogen peroxide decay.

Hydrometallurgical Purification of Metallurgical Grade Silicon with Hydrogen Peroxide in Hydrofluoric Acid

The effect of adding hydrogen peroxide (H2O2) as an oxidizing agent on purifying metallurgical grade silicon (MG-Si) by leaching with hydrofluoric acid (HF) was studied as a function of leaching temperature, particle size, leaching duration and concentration of leaching agents. It was found that the extraction capacity for metallic impurities could be significantly enhanced with introducing H2O2 into HF lixiviant showing litter dependence on HF concentration. By leaching with 1 mol· L-1 HF plus 2 mol· L-1 H2O2 for only 0.25 h at 55 ℃, the MG-Si purity could be upgraded from 99.74% to 99.96%, to 99.99% with further prolonging leaching duration. The sensitivity sequences of precipitates to each etchant were obtained through revealing the micro-structural evolution of MG-Si before and after etching. With the help of Raman spectrometry, it was reasonable that etching silicon starts with first oxidizing reaction by H2O2 and then dissolved by HF. Like Si-Si bonds, some Si-F and Si-O bonds could also be found on silicon surface after acid etching with HF plus H2O2 etchant. After acid leaching, the zigzag silicon surface had been detected by using transmission electron microscopy analysis and the formation mechanism was further discussed. Figure 1

The Human NADPH Oxidase, Nox4, Regulates Cytoskeletal Organization in Two Cancer Cell Lines, HepG2 and SH-SY5Y.

NADPH oxidases of human cells are not only functional in defense against invading microorganisms and for oxidative reactions needed for specialized biosynthetic pathways but also during the past few years have been established as signaling modules. It has been shown that human Nox4 is expressed in most somatic cell types and produces hydrogen peroxide, which signals to remodel the actin cytoskeleton. This correlates well with the function of Yno1, the only NADPH oxidase of yeast cells. Using two established tumor cell lines, which are derived from hepatic and neuroblastoma tumors, respectively, we are showing here that in both tumor models Nox4 is expressed in the ER (like the yeast NADPH oxidase), where according to published literature, it produces hydrogen peroxide. Reducing this biochemical activity by downregulating Nox4 transcription leads to loss of F-actin stress fibers. This phenotype is reversible by adding hydrogen peroxide to the cells. The effect of the Nox4 silencer RNA is specific for this gene as it does not influence the expression of Nox2. In the case of the SH-SY5Y neuronal cell line, Nox4 inhibition leads to loss of cell mobility as measured in scratch assays. We propose that inhibition of Nox4 (which is known to be strongly expressed in many tumors) could be studied as a new target for cancer treatment, in particular for inhibition of metastasis.

Effect of oxygen supply on milk-clotting activity expressed by Paenibacillus spp. strain BD3526

Paenibacillus spp. BD3526, a novel bacteria species isolated from raw yak (Bos grunniens) milk collected in Tibet, is able to produce metalloproteinase with milk-clotting activity (MCA) in wheat bran broth. To determine the critical factor favoring enzyme productivity, response surface methodology and the Box-Behnken design were adopted to preliminarily optimize BD3526 cultivation conditions for maximum MCA in shaking flasks. The highest degree of MCA (7072 ± 519 SU/mL) was obtained at a liquid volume of 30 mL and 300 r/min, which implies that oxygen supply is crucial for enzyme synthesis. MCA levels were enhanced as agitation speeds and aeration rates were increased in a 7-L scale fermentor. MCA in the supernatant was further boosted by adding hydrogen peroxide (H2O2) to the broth during cultivation. Maximum MCA (14778 ± 1100 SU/mL) and MCA/proteolytic activity (PA) (33000 ± 918) were achieved when cultivation was carried out at an agitation speed of 400 r/min, aeration rate of 5.5 L/min and H2O2 flow of 500 mmol/L at a feeding rate of 2.5 mL/h after 24 h of cultivation.

Ternary Pt-Co-Cu nanodendrites for ultrasensitive voltammetric determination of insulin at very low working potential

The interference by dissolved oxygen is an obstacle in electrochemical immunoassays. The authors are reporting here on a method that employs a working potential that is below the reduction potential for oxygen and hence is not interfered by oxygen/air. Ternary Pt-Co-Cu nanodendrites were prepared by a one-pot reaction. They were placed on a glassy carbon electrode (GCE) modified with gold nanoparticles (AuNPs) where they showed excellent catalytic activity toward the reduction of hydrogen peroxide at a reduction potential of −0.015 V (vs. SCE). Dissolved oxygen, in contrast, is not reduced at this potential. In order to obtain a sandwich-type of voltammetric immunosensor, antibody against insulin (Ab1) immobilized on the AuNPs on the GCE. The secondary antibody (Ab2) was labeled with Pt-Co-Cu nanodendrites as signal marker for signal amplification. After adding hydrogen peroxide, its catalytic oxidation by the immunosensor depends on its loading with insulin. Hence, insulin can be quantified due to the positive correlation that exists between current and the concentration of ternary Pt-Co-Cu nanodendrites on the electrode. The sensor has a linear response in the 0.2 pM to 2 nM insulin concentration range, with a 0.08 pM detection limit. The assay is well reproducible, acceptably selective, and the sensor is fairly stable over time.

Nucleic acid sensing with enzyme-DNA binding protein conjugates cascade and simple DNA nanostructures.

A versatile and universal DNA sensing platform is presented based on enzyme-DNA binding protein tags conjugates and simple DNA nanostructures. Two enzyme conjugates were thus prepared, with horseradish peroxidase linked to the dimeric single-chain bacteriophage Cro repressor protein (HRP-scCro) and glucose oxidase linked to the dimeric headpiece domain of Escherichia coli LacI repressor protein (GOx-dHP), and used in conjunction with a hybrid ssDNA-dsDNA detection probe. This probe served as a simple DNA nanostructure allowing first for target recognition through its target-complementary single-stranded DNA (ssDNA) part and then for signal generation after conjugate binding on the double-stranded DNA (dsDNA) containing the specific binding sites for the dHP and scCro DNA binding proteins. The DNA binding proteins chosen in this work have different sequence specificity, high affinity, and lack of cross-reactivity. The proposed sensing system was validated for the detection of model target ssDNA from high-risk human papillomavirus (HPV16) and the limits of detection of 45, 26, and 21pM were achieved using the probes with scCro/dHP DNA binding sites ratio of 1:1, 2:1, and 1:2, respectively. The performance of the platform in terms of limit of detection was comparable to direct HRP systems using target-specific oligonucleotide-HRP conjugates. The ratio of the two enzymes can be easily manipulated by changing the number of binding sites on the detection probe, offering further optimization possibilities of the signal generation step. Moreover, since the signal is obtained in the absence of externally added hydrogen peroxide, the described platform is compatible with paper-based assays for molecular diagnostics applications. Finally, just by changing the ssDNA part of the detection probe, this versatile nucleic acid platform can be used for the detection of different ssDNA target sequences or in a multiplex detection configuration without the need to change any of the conjugates. Graphical abstract DNA sensing platform based on an immobilized ssDNA capture probe and a hybrid ssDNA-dsDNA detection probe that specifically hybridize with the ssDNA target. The hybrid ssDNA-dsDNA detection probe also provides the binding sites for the enzyme-DNA binding protein conjugates (HRP-scCro and GOx-dHP) that generate the colorimetric signal.

APLICAÇÃO DO PROCESSO FENTON PARA DESCONTAMINAÇÃO DE HIDROCARBONETOS AROMÁTICOS EM ÁGUA

O processo Fenton é um processo oxidativo avançado (POA) muito utilizado devido sua alta eficiência e simplicidade, e consiste na adição do peróxido de hidrogênio na presença de Fe+2. O objetivo deste trabalho é o estudo da descontaminação da água contaminada pelo contato direto com gasolina. A aplicação dos reagentes segue um planejamento experimental 2² com ponto central, variando a concentração dos reagentes, cada amostra foi analisada nos tempos de 1 e 3 horas. Junto ao Fe+2 foi utilizado Cu+2 para avaliar a influência desta mistura na reação. As amostras foram extraídas com hexano e caracterizadas por cromatografia gasosa, analisando a porcentagem de hidrocarbonetos removidos. Utilizando apenas Fe+2 obteve-se degradações superiores a 60%. A adição de Cu+2 apesar de viável apresentou resultados inferiores, em alguns casos os resultados obtidos não foram conclusivos. Observou-se também que a remoção destes compostos requer tempo de reação superior a 1 hora para ser efetiva.

A Novel Near-Infrared Fluorescence Sensor for H<sub>2</sub>O<sub>2</sub> Based on N-Acetyl-L-Cysteine-Capped Gold Nanoparticles

A novel near-infrared fluorescence quenching method has been developed for the determination of hydrogen peroxide based on N-acetyl-L-cysteine-capped gold nanoparticles (NAC-AuNPs) as a fluorescence probe. The prepared gold nanoparticles with the size of about 1.91 nm exhibited strong near-infrared fluorescence emission at 693 nm with excitation wavelength at 450 nm in aqueous solution. The fluorescence intensity of NAC-AuNPs was quenched dramatically by adding hydrogen peroxide. Therefore, it could be used to detect hydrogen peroxide based on the fluorescence quenching intensity was linear with the concentration of hydrogen peroxide. Under the optimal experimental conditions, the linear range and detection limit were 1.0×10-6 –3.0×10-2 mol/L and 1.0×10-7 mol/L, respectively. The possible quenching mechanism was investigated by time-resolved fluorescence spectroscopy. The proposed method was simple, sensitive and showed good repeatability and stability.

Options and limitations for bromate control during ozonation of wastewater

Wastewater treatment plants (WWTPs) are important point sources for micropollutants, which are harmful to freshwater organisms. Ozonation of wastewater is a powerful option to abate micropollutants, but may result in the formation of the potentially toxic oxidation by-product bromate in bromide-containing wastewaters. This study investigates options to reduce bromate formation during wastewater ozonation by (i) reducing the bromide concentration of the wastewater, (ii) lowering the ozone dose during wastewater treatment and (iii) adding hydrogen peroxide to limit the lifetime of ozone and quench the intermediates of the bromate formation pathway. Two examples demonstrate that a high share of bromide in wastewater can originate from single point sources (e.g., municipal waste incinerators or landfills). The identification of major point sources requires laborious sampling campaigns, but may facilitate the reduction of the bromide load significantly. To reduce the bromate formation by lowering the ozone dose interferes with the aim to abate micropollutants. Therefore, an additional treatment is necessary to ensure the elimination of micropollutants. Experiments at a pilot-plant illustrate that a combined treatment (ozone/powdered activated carbon) allows to eliminate micropollutants with low bromate yields. Furthermore, the addition of hydrogen peroxide was investigated at bench-scale. The bromate yields could be reduced by ∼50% and 65% for a hydrogen peroxide dose of 5 and 10 mg L−1, respectively. In conclusion, there are options to reduce the bromate formation during wastewater ozonation, however, they are not simple with sometimes limited efficiency.

Pyrite oxidation in column at controlled redox potential of 900 mV with and without bacteria

Comparisons on the bioleaching and sterile oxidation of pyrite were performed at controlled redox potential of 900 mV (vs. SHE) and different temperatures of 30 and 60 °C. For sterile experiments, the redox potential of irrigation solution was controlled by adding hydrogen peroxide solution (15 wt%), while the redox potential of irrigation solution for bioleaching was elevated by flowing through the packed bed in which bacteria were activated and colonized. The rate of pyrite bioleaching is faster than that of sterile oxidation at temperature of 30 °C. The reason is that the potential gradient of leaching solution in bioleaching column is much smaller than that in sterile column. The redox potentials of irrigation solution and leaching solution are similar for bioleaching; however, the redox potential difference of irrigation solution and leaching solution for sterile oxidation is about 150 mV. When temperature increases to 60 °C for sterile oxidation, the rate of pyrite leaching is faster than that of bioleaching at temperature of 30 °C, even though the redox potential gradient of leaching solution is great. The mineralogy analyses of pyrite residue were performed by scanning electron microscopy–energy-dispersive spectroscopy (SEM–EDS), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses. The results confirm that pyrite oxidation might only occur at specific sites with high surface energy on surface and obeys the “indirect mechanism” whether there are bacteria or not. The pyrite oxidation rate is not inhibited by inert sulfur on residue surface at elevated redox potential. According to the conclusions, the way to accelerate pyrite oxidation is proposed.

Effets des substrats de peroxyde d’hydrogène et d’oxydase sur la motilité du sperme de bélier

Dans cette étude, les effets de l’ajout de peroxyde d’hydrogène (H2O2), de nicotinamide adénine dinucléotide phosphate (NADPH) et de phénylalanine (substrats spécifiques d’oxydases) sur la mobilité des spermatozoïdes ont été étudiés. On a incubé des frais spermatozoïdes d’Awassi belier à 37 ºC pendant 30, 60, 120 et 180 minutes avec (100 uM et 1 mM) ou sans H2O2, NADPH et phénylalanine dans des milieux de Tris (EYT) et de Tyrode Albumen Lactate (TAL). La mobilité des spermatozoïdes a été évaluée à l’aide d’une analyse du sperme assistée par ordinateur (CASA). Après l’incubation des spermatozoïdes avec 100 μM de H2O2 aux différents intervalles de temps, aucun changement significatif (P> 0,05) n’a pas été observé comparé au contrôle par le pourcentage de mobilité (MOT%), la mobilité progressive (PMOT%) et la vitesse moyenne (VAP). L’incubation avec 1 mM de H2O2 a entraîné une diminution significative (P

Hydrometallurgical Purification of Metallurgical Grade Silicon with Hydrogen Peroxide in Hydrofluoric Acid

The effect of adding hydrogen peroxide (H2O2) as an oxidizing agent on purifying metallurgical grade silicon (MG-Si) by leaching with hydrofluoric acid (HF) was studied as a function of leaching temperature, particle size, leaching duration, and concentration of leaching agents. It was found that the extraction capacity for metallic impurities could be significantly enhanced with introduction of H2O2 into HF lixiviant with little dependence on HF concentration. Upon leaching with 1 mol·L–1 HF and 2 mol·L–1 H2O2 for only 0.25 h at 55 °C, the MG-Si purity could be upgraded from 99.74% to 99.96%, to 99.99% with further prolonging of leaching duration. The sensitivity sequences of precipitates to each etchant were obtained through revealing the microstructural evolution of MG-Si before and after etching. With the help of Raman spectrometry and transmission electron microscopy, the chemical etching mechanism is discussed.

Sub-lethal oxidative stress induces lysosome biogenesis via a lysosomal membrane permeabilization-cathepsin-caspase 3-transcription factor EB-dependent pathway.

Here we provide evidence to link sub-lethal oxidative stress to lysosome biogenesis. Exposure of cells to sub-lethal concentrations of exogenously added hydrogen peroxide resulted in cytosol to nuclear translocation of the Transcription Factor EB (TFEB), the master controller of lysosome biogenesis and function. Nuclear translocation of TFEB was dependent upon the activation of a cathepsin-caspase 3 signaling pathway, downstream of lysosomal membrane permeabilization and accompanied by a significant increase in lysosome numbers as well as induction of TFEB-dependent lysosome-associated genes expression such as Ctsl, Lamp2 and its spliced variant Lamp2a, Neu1, Ctsb, Sqstm1, and Atg9b. The effects of sub-lethal oxidative stress on lysosomal gene expression and biogenesis were rescued upon gene silencing of caspase 3 and TFEB. Notably, caspase 3 activation was not associated with phenotypic hallmarks of apoptosis, evidenced by the absence of caspase 3 substrate cleavage, such as PARP, Lamin A/C or gelsolin. Taken together, these data demonstrate for the first time an unexpected and non-canonical role of a cathepsin-caspase 3 axis in the nuclear translocation of TFEB leading to lysosome biogenesis under conditions of sub-lethal oxidative stress.