Fenton-like Catalytic Activity Research Articles

Photothermal-Enhanced Fenton-like Catalytic Activity of Oxygen-Deficient Nanotitania for Efficient and Safe Tooth Whitening.

The growing demand for charming smiles has led to the popularization of tooth bleaching procedures. Current tooth bleaching products with high-concentration hydrogen peroxide (HP, 30-40%) are effective but detrimental due to the increased risk of enamel destruction, tooth sensitivity, and gingival irritation. Herein, we reported a less-destructive and efficient tooth whitening strategy with a low-concentration HP, which was realized by the remarkably enhanced Fenton-like catalytic activity of oxygen-deficient TiO2 (TiO2-x). TiO2-x nanoparticles were synthesized with a modified solid-state chemical reduction approach with NaBH4. The Fenton-like activity of TiO2-x was optimized by manipulating oxygen vacancy (OV) concentration and further promoted by the near-infrared (NIR)-induced photothermal effect of TiO2-x. The TiO2-x sample named BT45 was chosen due to the highest methylene blue (MB) adsorption ability and Fenton-like activity among acquired samples. The photothermal property of BT45 under 808 nm NIR irradiation was verified and its enhancement on Fenton-like activity was also studied. The BT45/HP + NIR group performed significantly better in tooth whitening than the HP + NIR group on various discolored teeth (stained by Orange II, tea, or rhodamine B). Excitingly, the same tooth whitening performance as the Opalescence Boost, a tooth bleaching product containing 40% HP, was obtained by a self-produced bleaching gel based on this novel system containing 12% HP. Besides, negligible enamel destruction, safe temperature range, and good cytocompatibility of TiO2-x nanoparticles also demonstrated the safety of this tooth bleaching strategy. This work indicated that the photothermal-enhanced Fenton-like performance of the TiO2-x-based system is highly promising in tooth bleaching application and can also be extended to other biomedical applications.

Irradiation of Fe–Mn@SiO2 with microwave energy enhanced its Fenton-like catalytic activity for the degradation of methylene blue

Irradiation of Fe–Mn@SiO2 with microwave energy enhanced its Fenton-like catalytic activity for the degradation of methylene blue

Green synthesis of magnetic \u03b1\u2013Fe2O3 nanospheres using Bridelia retusa leaf extract for Fenton-like degradation of crystal violet dye

The reach of nanotechnology has permeated into a range of disciplines and systematically revolutionized many manufacturing techniques. Today, nanoparticles are fabricated using varied approaches, each with its pros and cons. Of them, the green synthesis approach has been very effective in terms of overall economics and the stability of nanoparticles. The current study investigates the use of the leaf extract of Bridelia retusa for the synthesis of iron oxide nanoparticles. Typical of these nanoparticles, no specific peak was discernible on employing UV–visible spectroscopy. The size, morphological features, and crystallinity of the nanoparticles were determined by employing scanning electron microscopy and electron diffraction spectroscopy. Almost uniformly sized at 38.58 nm, the nanoparticles were spherical, constituting elemental iron at 11.5% and elemental oxygen at 59%. Their relative composition confirmed the nanoparticles to be iron oxide. X-ray diffraction studies showed the particles to be hexagonal and rhombohedral, estimating the crystallite size at 24.27 nm. BET analysis put the pore volume at 0.1198 cm3/g and pore diameter at 7.92 nm. The unique feature of the nanoparticles was that the specific surface area was 75.19 m2/g, which is more than 12 times higher than commercial α-Fe2O3. The participation of a variety of biochemicals in the leaf extract towards the reduction-cum-stabilization was confirmed using FTIR analysis. The Fenton-like catalytic activity of the nanoparticles was put to test by attempting to degrade crystal violet dye, which was completely achieved in 270 min. The kinetics of the degradation was also modelled in the study.

Transdermal delivery of Cu-doped polydopamine using microneedles for photothermal and chemodynamic synergistic therapy against skin melanoma

Multimodal nanoformulations with limited side-effects for tumor theranostics that catalyze a cascade of intracellular reactions show great potentials for tumor treatment with high specificity and efficiency. In this study, Cu-doped polydopamine nanoparticles (Cu-PDA NPs) have been prepared and embedded into microneedles (MNs) for photothermal and chemodynamic synergistic therapy against skin melanoma, by virtue of enhanced drug transdermal delivery owing to the unique core–shell structure of MNs. This multimodal tumor therapeutic strategy accumulates the high photothermal effect of Cu-PDA NPs (~50.40%) to acquire the energy from NIR irradiation and convert it into heat, and good Fenton-like catalytic activity of Cu+ ions to produce toxic free hydroxyl groups (‧OH) by reaction with excessive H2O2 in tumor cells, leading to the generation of a new minimally invasive synergistic therapy. The B16F10 mouse melanoma model demonstrates that the active delivery of Cu-PDA NPs results in greatly inhibit proliferation of tumor and induce mixed necrosis/apoptosis of tumor cells in vivo. This study offers a new avenue for the development of microneedles-based microdevices for skin melanoma by a minimally invasive delivery of multimodal nanoformulation.

Bisphenol A cleanup over MIL-100(Fe)/CoS composites: Pivotal role of Fe–S bond in regenerating Fe2+ ions for boosted degradation performance

Series of MIL-100(Fe)/CoS composites (MxCy) were facilely fabricated using ball-milling method. The optimum M50C50 exhibited extremely higher Fenton-like catalytic degradation activity toward bisphenol A (BPA) than the pristine MIL-100(Fe) and CoS. The significant improvement of BPA degradation was attributed to the synergetic effect between MIL-100(Fe) and CoS with the synergistic factor being 95.7%, in which the Fe–S bonds formed at the interface of the two components facilitate the Fe3+/Fe2+ cycle by improving the electron mobility both from Co to Fe and from S to Fe. Furthermore, the influence factors like co-existing inorganic ions and pH values on the catalysis activity of M50C50 were explored. The possible reaction mechanism was proposed and confirmed by both active species capture tests and electron spin resonance (ESR) determinations. It was found that M50C50 demonstrated good reusability and water stability, in which the morphology and structure were not changed obviously after five runs’ operation. To our best knowledge, it is the first work concerning the interfacial interaction of Fe-MOF/MSx to promote Fe3+/Fe2+ cycle in Fe-MOFs for the purpose of organic pollutants degradation in the Fenton-like AOPs system.

Enhanced Fenton-like catalytic activity and stability of g-C3N4 nanosheet-wrapped copper phosphide with strong anti-interference ability: Kinetics and mechanistic study

Metal-based Fenton-like catalysts usually activate H2O2 to produce free radicals (•OH and O2•−) for the degradation of organic pollutants. However, a catalytic reaction dominated by free radicals is easily interfered with by various inorganic anions and water matrices. Herein, g-C3N4-wrapped copper phosphide (CuxP), as a highly efficient Fenton-like catalyst, was successfully synthesized by a simple low-temperature phosphidation method. The CuxP/g-C3N4 catalyst exhibited excellent catalytic ability for the removal of various organic contaminants over a wide pH range of 3–11. In addition, the catalyst exhibited strong anti-interference ability toward various inorganic anions (Cl–, SO42–, NO3–, F–, H2PO4–, HCO3– and CO32–) and water matrices (lake water, river water, tap water and simulated water matrix). The reasons for this performance were analyzed by verifying the mechanism of the catalytic reaction. Compared to the pure CuxP catalyst, the CuxP/g-C3N4 composite possessed good catalytic stability. The enhanced and deactivated mechanisms of the CuxP/g-C3N4 catalyst were systematically analyzed by a series of characterization techniques. A possible reaction mechanism was also proposed based on the experimental results. This work provides new insights into designing highly efficient metal-based Fenton-like catalysts with strong anti-interference ability to practically treat wastewater.

Facile pH-controlled synthesis of MnWO4 nanoparticles and nanorods and their heterogeneous Fenton-like catalytic activity

MnWO4 nanoparticles and nanorods were respectively synthesized in the different pH of reactant solutions by a hydrothermal method. It was found that the pH of reactant solutions not only determined the purity and morphology of the synthesized MnWO4, but also determined the sizes of MnWO4 nanorods. MnWO4 nanoparticles had bigger specific surface area than the obtained different sizes of MnWO4 nanorods. For the degradation of aqueous methylene blue (MB), MnWO4 nanoparticles showed both larger adsorption capacity and higher Fenton-like catalytic activity as compared with MnWO4 nanorods. The mechanism study results demonstrated that the Fenton-like catalytic activity of MnWO4 is predominantly from WO42–. This study suggests that insoluble metal tungstates are a kind of promising heterogeneous Fenton-like catalysts.

Electrospun Zn Doped CuFe2O4 Nanofibers with Enhanced Photo Fenton-Like Catalytic Activity

One dimensional Zn doped CuFe₂O₄ spinel ferrite nanofibers were successfully prepared via a facile electrospinning method followed by two different calcination routes. The results showed that the as-prepared nanofibers through two-step calcination exhibited more uniform size distribution in diameter compared with those calcined by one-step method. X-ray diffraction (XRD) results indicated that with the increase of Zn content the position of diffraction peaks of Zn doped CuFe₂O₄ slightly shift towards lower 2θ angle because the ionic sizes of the Zn2+ (0.74 Å) is larger than that of Cu2+ (0.69 Å). Fourier transform infrared spectroscopy (FTIR) results showed that with increasing Zn content the position of vibrational band (590 cm-1) shifted towards the smaller wavenumber. Generally, photo-generated carriers increased with the increasing of Zn content. The photo Fenton-like catalytic results revealed that the doping of Zn facilitated the enhancement of degradation efficiency of catalysts. Additionally, 10 at.% Zn doped CuFe₂O₄ exhibited the best photo Fenton-like catalytic activity and the degradation efficiency of Rhodamine B (RhB) could reach 100% in 40 min. Finally, the enhancement of photo Fenton-like catalytic mechanism of the Zn doped CuFe₂O₄ nanofibers was mainly attributed to actived spinel structure lattice by Zn doping, which allows more Cu2+ and Fe3+ ions are involved in the photo Fenton-like catalytic reaction.

Iron Oxide-Silica Xerogel Synthesized Using Recovered Liquid and Their Fenton Degradation of Rhodamine B in Water

Iron oxide-silica hybrid xerogels were repeatedly synthesized using the liquid recovered during the drying of wet gels obtained in the previous run. The hybrid xerogels were characterized by SEM, FT-IR, and N2-sorption, DR UV–Vis techniques. The results indicate that the hybrid xerogels possess high surface areas from 514 to 601 m2/g with highly dispersed Fe species. The synthesized iron oxide-silica hybrid xerogels showed high adsorption capacity and Fenton-like catalytic activity toward Rhodamine B in aqueous solution over a wide pH range of 3–11. It was demonstrated that the hybrid xerogels remained excellent recyclability and stability for 5 cycles, with above 99% of the degradation efficiency being achieved and low iorn-leaching per cycle.

Bimetal-organic frameworks with coordinatively unsaturated metal sites for highly efficient Fenton-like catalysis

Recently, Fe–based metal–organic frameworks (Fe–MOFs) have been widely investigated as Fenton-like catalysts for environmental applications. However, their catalytic performance is limited by the insufficient number of Lewis acid sites for hydrogen peroxide (H2O2) activation and the slow Fe(III)–Fe(II) conversion. To overcome these limitations, coordinatively unsaturated iron–copper bimetallic sites may serve as Lewis acid sites, thus enhancing Fenton-like catalytic activity. Herein, we successfully synthesized a new Fenton-like catalyst of CUMSs/MIL-101(Fe,Cu), i.e., MIL-101 (MIL, Matérial Institute Lavoisier) with mixed valence of Fe(II)/Fe(III) and Cu(I)/Cu(II) as coordinatively unsaturated metal sites (CUMSs). Further, we evaluated the performance of catalytically activating H2O2 for ciprofloxacin (CIP) degradation. The results indicate a rapid CIP degradation by dosing CUMSs/MIL-101(Fe,Cu) (0.1 g·L−1) and H2O2 (3 mM) in the neutral pH range, with a 20-fold higher apparent rate constant than in a MIL-101(Fe)/H2O2 system. Various conditions of initial pH, catalyst amount, H2O2 concentration, and coexisting anions on the CIP degradation were systematically investigated for optimizing CIP degradation. Furthermore, we identified the intermediates during the CIP degradation and proposed the possible degradation pathways. We concluded that the thermodynamically favorable reaction between Cu(I) and Fe(III) and π–cation interactions accelerate the redox cycles of Fe(II)/Fe(III) and Cu(I)/Cu(II) CUMSs and this effect improves the Fenton-like performance over a broad pH range. Density functional theory calculations further clarified the dissociation process and the corresponding energy barriers of H2O2 at the atomic level. This work offers a new way for designing highly efficient, stable and harmless Fenton-like catalysts for achieving excellent environmental remediation efficiency over a wide pH range.

Smart Porous Core–Shell Cuprous Oxide Nanocatalyst with High Biocompatibility for Acid‐Triggered Chemo/Chemodynamic Synergistic Therapy

The rational integration of chemotherapy and hydroxyl radical (·OH)-mediated chemodynamic therapy (CDT) holds great potential for cancer treatment. Herein, a smart biocompatible nanocatalyst based on porous core-shell cuprous oxide nanocrystals (Cu2 O-PEG (polyethylene glycol) NCs) is reported for acid-triggered chemo/chemodynamic synergistic therapy. The in situ formed high density of hydrophilic PEG outside greatly improves the stability and compatibility of NCs. The porosity of Cu2 O-PEG NCs shows the admirable capacity of doxorubicin (DOX) loading (DOX@Cu2 O-PEG NCs) and delivery. Excitingly, Cu (Cu+/2+ ) and DOX can be controllably released from DOX@Cu2 O-PEG NCs in a pH-responsive approach. The released Cu+ exerts Fenton-like catalytic activity to generate toxic ·OH from intracellular overexpressed hydrogen peroxide (H2 O2 ) for CDT via reactive oxygen species (ROS)-involved oxidative damage. Exactly, DOX can not only induce cell death for chemotherapy but also enhance CDT by self-supplying endogenous H2 O2 . After the intravenous injection, Cu2 O-PEG NCs can effectively accumulate in tumor region via passive targeting improved by external high-density PEG shell. Additionally, the effect of boosted CDT combined with chemotherapy presents excellent in vivo antitumor ability without causing distinct systemic toxicity. It is believed that this smart nanocatalyst responding to the acidity provides a novel paradigm for site-specific cancer synergetic therapy.

A Metal-Polymer Hybrid Biomimetic System for use in the Chemodynamic-Enhanced Photothermal Therapy of Cancers.

This article reports the fabrication of a smart biomimetic enzyme system, which incorporates a pH-responsive chemodynamic therapy (CDT) combined with a photothermal (PTT) therapy approach in resolving the high recurrence rate of deadly cancers. The resulting enzyme system comprises copper sulfide (CuS) nanoparticle (NP) cores as Fenton-like catalysts, and a photothermal-active generation 5 poly(amidoamine) (G5) dendrimer as a template for the entrapment of Cu NPs and the compression of glucose oxidase (GOD). GOD is introduced to produce H2 O2 necessary in the sequential Fenton-like reaction, and this generates hydroxyl radicals that kill the cancerous cells. Polyethylene glycol is added to the system to improve biocompatibility. Mechanism study suggests that the constructed CuS/G5-GOD-based system has a better Fenton-like catalytic activity than a Fe3 O4 -GOD-based system. This allows the further inhibition on the residual tumors from recurrence and metastasis through CDT after being treated by PTT. The developed smart nanoscale biomimetic system shows high efficiency for breast cancer suppression from recurrence and metastasis by combining PTT with a pH-responsive CDT. It has the potential to resolve the essential issue of cancer recurrence after its initial clinic treatment.

Effect of doping and surfactant on the structural and Fenton-like catalytic activity of digenite structures synthesized by a solvothermal method

Pure, Co, and Ho-doped digenite (Cu9S5 or Cu1.8S) nanostructures were synthesized through simple solvothermal approaches. The effect of surfactant) Tween 20, polyethylene glycol, and oleic acid) on the morphology and optical properties of nanostructures was investigated in detail. The plasmonic band of samples synthesized in the presence of Tween 20 and oleic acid was reduced because of trapping of Cu vacancies by the carboxylate groups of surfactants. In addition, the surfactants adsorbed on the nanostructure surface have a negative impact on catalytic activity of particles, while the Fenton-like activity of doped catalysts yielded good performance in terms of methylene blue (MB) decolorization (98% and 90% for Ho and Co doping Cu1.8S, respectively). Ho improves redox cycling of Cu2+ to Cu+ and Co improves reactivity with H2O2 accelerate MB decolorization.

Biomimetic Metal-Organic Framework Composite-Mediated Cascade Catalysis for Synergistic Bacteria Killing.

Encapsulating nanoparticles/biomolecules into metal-organic freamworks (MOFs) has proven to be highly effective in creating new functions during their applications. However, it is highly desirable yet remains challenging to achieve the synergy of specific functions between the MOF host and guest species. Herein, inspired by the natural multienzyme system, a novel MOF composite biomimetic structure based on the coencapsulation of glucose oxidase (GOx) and l-arginine (l-Arg) into Cu-MOFs (CuBDC) with Fenton-like catalytic activity is designed for achieving the synergistic antibacterial effect. Once activated by GOx-catalyzed glucose oxidation, a large amount of oxygen radicals, toxic ONOO-, and NO are rapidly produced over this well-designed l-Arg/GOx@CuBDC through a double-cascade reaction. Thanks to the synergy of highly reactive species, outstanding antibacterial effects (bacterial inactivation ≥97%) are observed at very low doses (38 μg mL-1 for Escherichia coli and 3.8 μg mL-1 for Staphylococcus aureus). In addition, the in vivo experiment in mice demonstrated that the as-prepared l-Arg/GOx@CuBDC has good biocompatibility, indicating its good potential in practical applications. Such a biomimetic multienzyme system proposes a new design idea for highly efficient antibiosis as well as even therapy for tumors.

Sacrificial template-directed fabrication of mesoporous manganese oxide based catalysts: Relationship between the ordering degree of pore structure and Fenton-like catalytic activity

In this study, novel mesoporous MnOx-based catalysts were prepared via the hard template method by using the mesoporous silica as a template. The performances of these catalysts were evaluated in catalytic wet H2O2 oxidation for Rhodamine B (RhB) in high-salinity wastewater (10% Na2SO4 solution containing RhB). The microstructure characterization indicated that the order of pore structures and the MnOx crystallinity in mesoporous materials improved as the number of repetitions of the immersion and calcination–molding process increased. Given good selective adsorption performance for RhB and rich Mn3+/Mn4+ couples, MnOx mesoporous materials with ordered regular pores exhibited excellent Fenton-like catalytic performance and the highest removal rate of RhB in high-salinity wastewater reached approximately 90% after 150 min of degradation. Moreover, because of the accelerated generation of the free radicals catalyzed by the Fe3+/Fe2+ couples, the loading of Fe species increased the performance of the MnOx ordered catalysts for RhB degradation. Furthermore, the Fe-loading MnOx catalyst exhibited only slight activity loss within the five cycles of catalytic degradation (the removal rate for RhB within the five cycles all exceeded 95%), due to the morphological stability of the MnOx ordered catalyst and the presence of stable Fe3+/Fe2+ couples during the RhB degradation process.

Co Single-Atom Catalysts Boost Chemiluminescence.

Co single-atom catalysts (SACs) with good aqueous solubility and abundant labelling functional groups were prepared in Co/Fe bimetallic metal-organic frameworks by a facile solvothermal method without high-temperature calcination. In contrast to traditional chemiluminescence (CL) catalysts, Co SACs accelerated decomposition of H2 O2 to produce a large amount of singlet oxygen (1 O2 ) rather than superoxide (O2 .- ) and hydroxyl radical (OH. ). They were found to dramatically enhance the CL emission of the luminol-H2 O2 reaction by 1349 times, and, therefore, were employed as very sensitive signal probes for conducting CL immunoassay of cardiac troponin I. The detection limit of the target analyte was as low as 3.3 pg mL-1 . It is the first time that employment of SACs for boosting CL reactions has been validated. The Co SACs can also be employed to trace other biorecognition events with high sensitivity.

In situ synthesis of Cu+ self-doped CuWO4/g-C3N4 heterogeneous Fenton-like catalysts: The key role of Cu+ in enhancing catalytic performance

In this work, novel Cu+ self-doped CuWO4/g-C3N4 composites were in situ synthesized through a simple hydrothermal method. The CuWO4 nanoparticles with the size of about 10 nm were dispersed uniformly on the surface of g-C3N4 nanosheets. The Fenton-like catalytic results showed that the 30 wt% CuWO4/g-C3N4 composite exhibited the best catalytic activity for the degradation of organic dyes. The enhanced Fenton-like catalytic activity could be ascribed to the promoted redox cycle of Cu+/Cu2+ in the presence of abundant Cu+ as well as the synergistic effect between CuWO4 and g-C3N4 in the CuWO4/g-C3N4 composites. In addition, the highly efficient catalysts could be used repeatedly to treat variety of organic pollutants in a wide pH range at room temperature without external energy input (light, electricity and ultrasound). The reactive species quenching experiments showed that singlet oxygen played the major role in the Fenton-like reaction for the degradation of organic dyes. Based on the above results, a possible reaction mechanism was proposed in the Cu+ self-doped CuWO4/g-C3N4/H2O2 system.

Persistent Luminescence Nanoplatform with Fenton-like Catalytic Activity for Tumor Multimodal Imaging and Photoenhanced Combination Therapy.

Reactive oxygen species-mediated tumor chemodynamic therapy and photodynamic therapy have captured extensive attention in practical cancer combination therapies. However, the severe treatment conditions and the hypoxic microenvironment of solid tumors significantly limit the efficacy of these therapies. This work demonstrates the design and fabrication of a multifunctional persistent luminescence nanoplatform (PHFI, refers to PLNP-HSA-Fe3+-IR780) for cancer multimodal imaging and effective photoenhanced combination therapy. The near-infrared-emitted persistent luminescence nanoparticles (PLNP) was modified with human serum albumin (HSA) combined with an IR780 probe and Fe3+. The synthesized PHFI possesses high longitudinal relaxivity, obvious photoacoustic contrast signals, and long-lasting persistent luminescence, indicating that PHFI can be used for cancer magnetic resonance imaging, photoacoustic imaging, and persistent luminescence multimodal imaging. PHFI shows intrinsic photoenhanced Fenton-like catalytic activities as well as photodynamic and photothermal effects and thereby can effectively overcome severe treatment conditions for killing tumor cells. It is worth noting that PHFI serving as a rechargeable internal light source for photoenhanced combination therapy was first disclosed. We believe that our work shows the great potential of PHFI for cancer theranostics and will advance the development of PLNP-based nanoplatforms in tumor catalytic therapy.

Hierarchical CuO microparticles constructed via underwater Leidenfrost process and their Fenton-like catalytic activity

In this report, a rapid and simple bottom-up approach to synthesize flower-like hierarchical CuO microparticles is demonstrated. Fabrication of microparticles with a mean size of 1.5 µm was successfully accomplished via hydrolysis of copper–ammonia complex at underwater dynamic Leidenfrost conditions and their structural, textural and chemical properties were examined. Besides, the Fenton-like catalytic activity of the as-prepared material is revealed by using caffeine micro-pollutant oxidation in aqueous solution. Complete degradation of caffeine with initial concentration of 10 ppm was observed after 170 min reaction time.

Ultrafine Titanium Monoxide (TiO1+x) Nanorods for Enhanced Sonodynamic Therapy.

Ultrasound (US)-triggered sonodynamic therapy (SDT) that enables noninvasive treatment of large internal tumors has attracted widespread interest. For improvement in the therapeutic responses to SDT, more effective and stable sonosensitizers are still required. Herein, ultrafine titanium monoxide nanorods (TiO1+x NRs) with greatly improved sono-sensitization and Fenton-like catalytic activity were fabricated and used for enhanced SDT. TiO1+x NRs with an ultrafine rodlike structure were successfully prepared and then modified with polyethylene glycol (PEG). Compared to the conventional sonosensitizer, TiO2 nanoparticles, the PEG-TiO1+x NRs resulted in much more efficient US-induced generation of reactive oxygen species (ROS) because of the oxygen-deficient structure of TiO1+x NR, which predominantly serves as the charge trap to limit the recombination of US-triggered electron-hole pairs. Interestingly, PEG-TiO1+x NRs also exhibit horseradish-peroxidase-like nanozyme activity and can produce hydroxyl radicals (•OH) from endogenous H2O2 in the tumor to enable chemodynamic therapy (CDT). Because of their efficient passive retention in tumors post intravenous injection, PEG-TiO1+x NRs can be used as a sonosensitizer and CDT agent for highly effective tumor ablation under US treatment. In addition, no significant long-term toxicity of PEG-TiO1+x NRs was found for the treated mice. This work highlights a new type of titanium-based nanostructure with great performance for tumor SDT.