Tailoring the peroxidase-like properties of Mo atom nanoclusters/N-MXene nanozymes for sensitive colorimetric detection of glutathione.

Although nanozyme engineering has made tremendous progress, there is a huge gap between them and natural enzymes due to the enormous challenge of precisely adjusting the geometric and electronic structure of active sites. Considering that intentionally adjusting the metal-carrier interactions may bring the promising catalytic activity, in this work, a novel Mo atom nanocluster is successfully synthesized using nitrogen-doped Mxene (MoACs/N-MXene) nanozymes as carriers. The constructed MoACs/N-MXene displays excellent peroxidase-like catalytic activity and kinetics, outweighing its N-MXene and Mo nanoparticles (NPs)-MXene references and natural horse radish peroxidase. This work not only reports a successful example of MoACs/N-MXene nanozyme as a guide for achieving peroxidase-mimic performance of nanozymes for colorimetric glutathione sensing at 0.29 µM, but also expands the application prospects of two-dimensional MXene nanosheets by reasonably introducing metal atomic clusters and nonmetal atom doping and exploring related nanozyme properties.

Platinum single atom on CsPbBr3 nanocrystals as electrocatalyst boosts electrochemical sensing of ascorbic acid.

Monitoring ascorbic acid (AA) levels in human body can provide valuable clues for disease diagnosis. Anchoring noble metal single atoms on perovskite substrate is a promising strategy to design electrocatalysts with outstanding electrocatalytic performance. Herein, we design an electrochemical method for detecting AA by utilizing Pt single atoms-doped CsPbBr3 nanocrystals (Pt SA/CsPbBr3 NCs) fixed on a glassy carbon electrode as an electrochemical catalyst. The uncharged 3,5,3',5'-tetramethylbenzidine (TMB) undergoes oxidation to form the positively charged oxidized TMB (oxTMB) owing to the exceptional electrochemical catalytic performance of Pt SA/CsPbBr3 NCs. Subsequently, the target AA reduces oxTMB to TMB, which is then electrocatalytically oxidized to oxTMB, producing significant oxidation current. In this way, such characteristic provides a sensitive electrochemical strategy for AA detection, achieving a concentration range of 50-fold with the detection limit of 0.0369 µM. The developed electrochemical method also successfully generates accurate detection response of AA in complex sample media (urine). Overall, this approach is expected to offer a novel way for early disease diagnosis.

Incidence, Predictors, and Implications of Secondary Aortic Intervention Following Thoracic Endovascular Aortic Repair for Type B Dissection.

BACKGROUND: Secondary aortic intervention (SAI) following thoracic endovascular aortic repair (TEVAR) is not uncommon. However, a satisfactory management system has not been established for these patients. We aimed to report our single-center experience with SAI after prior TEVAR for type B aortic dissection (TBAD). METHODS: From January 2010 to May 2017, 860 eligible patients with TBAD underwent TEVAR. One hundred seven (12.4%) patients required SAI, either endovascularly (n=76) or surgically (n=31). The main indications for SAI were entry flow (n=58 [54.2%]), aneurysm expansion of the proximal or remote aorta (n=26 [24.3%]), retrograde type A aortic dissection (n=11 [10.3%]), distal stent-graft-induced new entry tear (n=6 [5.6%]), and stent migration (n=4 [3.7%]). The Kaplan-Meier curves were generated to determine the degree of freedom from SAI and the prognosis. Cox proportional hazards were used to screen for risk factors for SAI and poor prognosis. RESULTS: The overall 30-day mortality rate after SAI was 4.7% (n=5): endovascular (n=2 [2.6%]) vs open surgery (n=3 [9.7%]; p=0.145). The cumulative survival rates with or without SAI were 86.3%±3.6% vs 95.7%±0.8% at 3 years and 82.0%±4.2% vs 92.2%±1.1% at 5 years, respectively (log-rank p<0.001). Although no significant difference in survival was observed, the incidence of SAI was significantly greater in patients who underwent TEVAR during the chronic phase (acute [11.6%] vs subacute [9.6%] vs chronic [27.8]; p<0.001). Multivariate regression analysis revealed that prior TEVAR in the chronic phase (hazard ratio [HR]=1.73, 95% confidence interval [CI]=1.03-2.90; p=0.039), maximum aortic diameter (HR=1.05, 95% CI=1.04-1.07; p<0.001), and arch involvement (HR=1.48, 95% CI=1.01-2.18; p=0.048) were predictors of the incidence of SAI. In addition, the maximum aortic diameter was demonstrated to be the only risk factor for prognosis after adjusting for confounding factors. CONCLUSIONS: Thoracic endovascular aortic repair for chronic TBAD patients should be reconsidered. Open surgery is preferable for those with proximal progression, whereas endovascular treatment is more suitable for distal lesions. Close surveillance and timely reintervention after TEVAR, whether via endovascular techniques or open surgery, are necessary to prevent devastating complications. CLINICAL IMPACT: The management of patients with type B aortic dissection (TBAD) after thoracic endovascular aortic repair (TEVAR) is challenging. We summarized our single-center experience regarding secondary aortic intervention after TEVAR for TBAD. We found that TEVAR for chronic TBAD patients should be carefully evaulated, and open surgery is recommended for those with proximal progession, while endovascular treatment is more preferable for distal lesions.

A three-dimensional network structure of metal-based nanozymes for the construction of colorimetric sensors for the detection of antioxidants.

Although many excellent nanozymes have been developed, designing and synthesizing highly active nanozymes is still challenging. Here, we developed a metal-based nanozyme (metal = Co, Fe, Cu, Zn) with a three-dimensional network structure. It possesses excellent peroxidase activity and catalyzes the reaction between H2O2 and TMB to produce blue oxTMB, while antioxidants have different reducing power on the oxidation product of TMB (oxTMB), which leads to different absorbance and color changes. Using these color reactions, different nanozymes were used to form a colorimetric sensor array with seven antioxidants, and seven antioxidants were sensitively identified. And the differences between the three nanozymes were compared by density functional theory calculations and enzyme kinetic curve results. In conclusion, the colorimetric sensor array based on metal-based nanozymes provides a good strategy for the identification and detection of antioxidants, which has a broad application prospect.

A dual channel fluorescence tongue for catechin recognition based on the MnO2 nanorods-Amplex Red-o-phenylenediamine reaction system.

Here, we report a dual-channel fluorescence sensor array for catechin discrimination based on the MnO2 nanorods (NRs)-Amplex Red (AR)-o-phenylenediamine (OPD) catalytic reaction system. MnO2 catalyzes both OPD and AR oxidation, and the fluorescence intensity values generated at 550 nm and 590 nm provide "fingerprints" for the sensor array. Different catechins have varying degrees of inhibitory effects on the MnO2 NRs-AR-OPD catalytic reaction system, thus obtaining unique fluorescence response fingerprints. Through linear discriminant analysis (LDA), the sensor array can not only successfully distinguish 5 catechins with concentrations as low as 500 nM and different concentrations of catechins, but also realize the identification of catechin mixtures. Notably, this method only requires the preparation of a single nanomaterial that catalyzes two substrates simultaneously and can generate two different fluorescence signal outputs, greatly facilitating the design of the sensor array.

A dual-channel sensor array for discrimination of biothiols based on manganese dioxide nanosheets.

A dual-signal sensor array for highly sensitive identification of biothiols is reported based on different optical responses of MnO2/curcumin (CUR) system to different biothiols. The addition of MnO2 nanosheets (MnO2 NSs) quenches the fluorescence of CUR, and the color of the mixture changes from yellow to brown. In the presence of reductive biothiols, MnO2 NSs are etched and lose their fluorescence quenching ability, resulting in an increase in the fluorescence intensity of CUR at 540 nm and a decrease in the absorbance at 430 nm. The sensor array generates specific response modes based on the varying reduction abilities of different biothiols, which can be distinguished by linear discriminant analysis (LDA). The sensor array successfully distinguished five biothiols (glutathione (GSH), dithiothreitol (DTT), cysteine (Cys), mercaptoethanol (ME), and homocysteine (Hcy)) across a wide concentration range (1 µM-100 µM) and biothiol mixtures with varing molar ratios.

Electrochemical aptamer biosensor for DNA detection based on label-free aptamers.

Electrochemical aptasensor has been broadly advanced for nucleic acid detection. However, it is a long-term goal to design an aptasensor with high specificity, flexibility, and simplicity. In this work, we develop a strategy of triblock DNA probe, which consists of two DNA probes at both ends and ployA fragments in the middle as probe-polyA-probe. PolyA fragment has high affinity to the surface of gold electrode, so it can be assembled on the electrode surface via polyA instead of traditional Au-S bonds. When the target DNA is simultaneously hybridized with the two capture probes, the hybridization stability can be improved due to the strong base stacking effect. [Ru(NH3)6]3+, as signal probe, can be electrostatically adsorbed on the negatively charged DNA skeleton. A wide linear range (10 pM-10 µM) is obtained with a detection limit of 2.9 pM. Our electrochemical aptasensor has good repeatability, stability, and specificity. More importantly, the electrochemical sensor can successfully detect DNA in human serum samples, which proves its practical value and extensive applicability in complex environment.

Electronic Metal-Support Interactions between Copper Nanoparticles and Nitrogen-Doped Ti3C2Tx MXene to Boost Peroxidase-like Activity for Detecting Astaxanthin.

Nanozymes with high activity and stability have emerged as a potential alternative to natural enzymes in the past years, but the relationship between the electronic metal-support interactions (EMSI) and catalytic performance in nanozymes still remains unclear. Herein, a copper nanoparticle nanozyme supported on N-doped Ti3C2Tx (Cu NPs@N-Ti3C2Tx) is successfully synthesized and the modulation of EMSI is achieved by introducing N species. The stronger EMSI between Cu NPs and Ti3C2Tx, involving electronic transfer and an interface effect, is revealed by X-ray photoelectron spectroscopy, soft X-ray absorption spectroscopy, and hard X-ray absorption fine spectroscopy at the atomic level. Consequently, Cu NPs@N-Ti3C2Tx nanozyme exhibits remarkable peroxidase-like activity, surpassing its counterpart (Cu NPs, Ti3C2Tx, Cu NPs-Ti3C2Tx), suggesting that EMSI significantly enhances catalytic performance. Benefiting from the excellent performance, the colorimetric platform based on Cu NPs@N-Ti3C2Tx nanozyme for detecting astaxanthin is constructed and shows a wide linear detection range of 0.01-50 µM and a limit of detection of 0.015 µM in the sunscreens. Density functional theory is further conducted to reveal that the excellent performance is ascribed to the stronger EMSI. This work opens an avenue for studying the influence of EMSI toward catalytic performance of nanozyme.

Cancer-Associated Fibroblast Risk Model for Prediction of Colorectal Carcinoma Prognosis and Therapeutic Responses.

Colorectal carcinoma (CRC) is a malignant tumor of the digestive system. Cancer-associated fibroblasts (CAFs) are important cellular elements in the tumor microenvironment of CRC, which contribute to CRC progression and immune escape. To predict the survival outcome and therapeutic responses of CRC patients, we identified genes connected with stromal CAF and generated a risk model. In this study, we used multiple algorithms to reveal CAF-related genes in the Gene Expression Omnibus and The Cancer Genome Atlas datasets and construct a risk model composed by prognostic CAF-associated genes. Then, we evaluated whether the risk score could predict CAF infiltrations and immunotherapy in CRC and confirmed the expression of the risk model in CAFs. Our results showed that CRC patients with high CAF infiltrations and stromal score had worse prognosis than those with low-CAF infiltrations and stromal score. We obtained 88 stromal CAF-associated hub-genes and generated a CAF risk model consisting of ZNF532 and COLEC12. Compared with low-risk group, the overall survival in high-risk group was shorter. The relationship between risk score, ZNF532 and COLEC12, and stromal CAF infiltrations and CAF markers was positive. In addition, the effect of immunotherapy in the high-risk group was not as good as that in the low-risk group. Patients with the high-risk group were enriched in chemokine signaling pathway, cytokine-cytokine receptor interaction, and focal adhesion. Finally, we confirmed that the expressions of ZNF532 and COLEC12 in risk model were widely distributed in fibroblasts of CRC, and the expression levels were higher in fibroblasts than CRC cells. In conclusion, the prognostic CAF signature of ZNF532 and COLEC12 can be applied not only to predict the prognosis of CRC patients but also to evaluate the immunotherapy response in CRC patients, and these findings provide the possibility for further development of individualized treatment for CRC.

Visual Sensor Arrays for Distinction of Phenolic Acids Based on Two Single-Atom Nanozymes.

Although great achievements have been made in the study of artificial enzymes, the design of nanozymes with high catalytic activities of natural enzymes and the further establishment of sensitive biosensors still remain challenging. Here, two nanozymes, i.e., ZnCoFe three-atom nanozyme (TAzyme) and Sn single-atom nanozyme (SAzyme)/Ti3C2Tx, are developed, which show peroxidase-like catalytic activities by catalyzing the reaction of hydrogen peroxide (H2O2), 4-aminoantipyrine (4-AAP), and phenolic acids to generate colorimetric reactions. The involvement of different phenolic acids leads to the generation of different color products. These subtle color-variation profiles between these phenolic acids prompt us to exploit an electronic tongue based on the two nanozymes to distinguish phenolic acids. Data interpretation by the pattern recognition method, such as linear discriminant analysis (LDA), displays good clustering separation of six different phenolic acids at concentrations of 0.1 µM to 1 mM, validating the effectiveness of the colorimetric nanozyme sensor array.

Colorimetric identification of multiple terpenoids based on bimetallic FeCu/NPCs nanozymes.

Nanozymes have been relatively well explored, and bimetal-doped nanozymes have attracted much exploration due to their superior catalytic activity. We developed bimetallic FeCu/NPCs and Cu/NPCs nanozymes, which have good catalytic properties due to the coordination of Fe and Cu with N and P. The nanozymes acted as sensing elements in a cascade reaction system to effectively recognize seven terpenoids, including menthol (Men), paeoniflorin (Pae), camphor (Cam), paclitaxel (Pac), andrographolide (Andro), ginkgolide A (Gin A), and piperone (Pip). Terpenoids act as inhibitors of acetylcholinesterase (AChE) and reduce the hydrolysis of acetylcholine (ATCh), providing insight into establishing a simple and distinct assay for terpenoids. Notably, the sensor array distinguished seven terpenoids with concentrations as low as 10 ng/mL and achieved high-precision detection of mixed samples with different molar ratios and 21 unknown samples. Finally, the sensor array successfully distinguished and identified multiple terpenoids in herbal samples.

Peroxidase-Like FeCoZn Triple-Atom Catalyst-Based Electronic Tongue for Colorimetric Discrimination of Food Preservatives.

Recently, single-atom catalysts are attracting much attention in sensor field due to their remarkable peroxidase- or oxidase-like activities. Herein, peroxidase-like FeCoZn triple-atom catalyst supported on S- and N-doped carbon derived from ZIF-8 (FeCoZn-TAC/SNC) serves as a proof-of-concept nanozyme. In this paper, a dual-channel nanozyme-based colorimetric sensor array is presented for identifying seven preservatives in food. Further experiments reveal that the peroxidase-like activity of the FeCoZn TAzyme enables it to catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) and o-phenylenediamine (OPD) in the presence of H2 O2 , yielding the blue oxTMB and yellow oxOPD, respectively. However, food preservatives are adsorbed on the nanozyme surface through π-π stacking interaction and hydrogen bond, and the reduction in catalytic activity of FeCoZn TAzyme causes differential colorimetric signal variations, which provide unique "fingerprints" for each food preservative.

Effects of Home-based Remote Cardiac Rehabilitation on Left Ventricular Function and Fear of Exercise in Patients after Percutaneous Coronary Intervention (PCI): A Retrospective Cohort Study.

AIM: This study aims to explore the effects of home-based remote cardiac rehabilitation on left ventricular function and exercise fear in patients after percutaneous coronary intervention (PCI). METHODS: A total of 232 patients with coronary heart disease after PCI treated in Tianshan Traditional Chinese Medicine Hospital from January 2020 to December 2022 were retrospectively analyzed. The patients were divided into the remote rehabilitation group (169 cases) and the routine group (63 cases) according to the exposure factor (home-based remote cardiac rehabilitation). Changes in left ventricular function and sports phobia Tampa Scale in patients with coronary heart disease after PCI were compared using propensity score matching to reduce selection bias and confounding factors. RESULTS: After the intervention, the scores of patients in the tele-rehabilitation group were significantly higher than those in the conventional group in terms of fear of movement, perception of danger, fear of movement, avoidance of movement, and dysfunction (p-value < 0.05). Left heart function was compared between the tele-rehabilitation group and the conventional group. Patients in the tele-rehabilitation group had significantly higher peak mitral valve blood flow in the early diastolic period (E), peak mitral valve blood flow in the late diastolic period (A), six-minute walk test (6MWT), and ratio of the peak mitral valve blood flow in the early diastolic period to the peak mitral valve blood flow in the late diastolic period (E/A) than those in the conventional group (p-value < 0.05). However, the peak deceleration time and isovolumic diastolic time in the early mitral valve diastolic period were significantly higher in the tele-rehabilitation group than in the conventional group (p-value < 0.05). CONCLUSIONS: Home-based remote cardiac rehabilitation instruction can improve the heart function and exercise fear state of patients after PCI.

Oxidase-like ZnCoFe Three-Atom Nanozyme as a Colorimetric Platform for Ascorbic Acid Sensing.

Great enthusiasm in single-atom catalysts for various catalytic reactions continues to heat up. However, the poor activity of the existing single/dual-metal-atom catalysts does not meet the actual requirement. In this scenario, the precise design of triple-metal-atom catalysts is vital but still challenging. Here, a triple-atom site catalyst of FeCoZn catalyst coordinated with S and N, which is doped in the carbon matrix (named FeCoZn-TAC/SNC), is designed. The FeCoZn catalyst can mimic the activity of oxidase by activating O2 into •O2- radicals by virtue of its atomically dispersed metal active sites. Employing this characteristic, triple-atom catalysts can become a great driving force for the development of novel biosensors featuring adequate sensitivity. First, the property of FeCoZn catalyst as an oxidase-like nanozyme was explored. The obtained FeCoZn-TAC/SNC shows remarkably enhanced catalytic performance than that of FeCoZn-TAC/NC and single/dual-atom site catalysts (FeZn, CoZn, FeCo-DAC/NC and Fe, Zn, Co-SAC/NC) because of trimetallic sites, demonstrating the synergistic effect. Further, the utility of the oxidase-like FeCoZn-TAC/SNC in biosensor field is evaluated by the colorimetric sensing of ascorbic acid. The nanozyme sensor shows a wide concentration range from 0.01 to 90 µM and an excellent detection limit of 6.24 nM. The applicability of the nanozyme sensor in biologically relevant detection was further proved in serum. The implementation of TAC in colorimetric detection holds vast promise for further development of biomedical research and clinical diagnosis.

Colorimetric sensing strategy for detection of cysteine, phenol cysteine, and phenol based on synergistic doping of multiple heteroatoms into sponge-like Fe/NPC nanozymes.

Nanozymes have both the high catalytic activity of natural enzymes and the stability and economy of mimetic enzymes. Research on nanozymes is rapidly emerging, and the continuous development of highly catalytic active nanozymes is of far-reaching significance. This work reports heteroatomic nitrogen (N) and phosphorus (P) double-doped mesoporous carbon structures and metallic Fe coordination generated sponge-like nanozymes (Fe/NPCs) with good peroxidase activity. On this basis, we constructed a highly sensitive colorimetric sensor with cysteine and phenol as simulated analytes using Fe/NPCs nanozymes, and the response limits reached 53.6 nM and 5.4 nM, respectively. Besides, the method has high accuracy in the detection of cysteine and phenol at low concentrations in serum and tap water, which lays a foundation for application in the fields of environmental protection and biosensors.

CsPbBr3 and CsPbBr3/SiO2 Nanocrystals as a Fluorescence Sensing Platform for High-Throughput Identification of Multiple Thiophene Sulfides.

Air pollution is a serious problem. Refractory thiophene sulfides, which cause air pollution, bring great challenges to their rapid and accurate identification. In this work, we propose a fluorescent sensor array based on two perovskite nanocrystals (CsPbBr3 NCs and CsPbBr3/SiO2 NCs) to distinguish different thiophene sulfides. The hydrogen bonding force between the thiophenics of thiophene sulfides and the amino groups of the perovskite NCs results in the weakening of the fluorescence signals of the perovskite NCs. The diverse interactions between thiophene sulfides and two perovskite NCs provide rich information, which can be obtained on the sensor array and identified by linear discriminant analysis. Five thiophene sulfides (i.e., benzothiophene, dibenzothiophene, 2-methylbenzothiophene, 3-methylthiophene, and thiophene) were discriminated by the sensor array at concentrations of 10-50 ppm. The effectiveness of the sensor array was further verified in the discrimination of blinded samples, in which all 10 samples were correctly identified. In addition, it is gratifying that even binary mixtures of thiophene sulfides could be distinguished by the proposed sensor array.

High throughput sensing of multiple amino acids with differential pulse voltammetry measurement.

The content of amino acids in human body is closely related to human health and plays an important role in physiological regulation and medical function. In order to recognize a variety of amino acids, an electrochemical sensor array based on poly(3,4-ethylenedioxythiophene) (PEDOT) electrode was established by using two kinds of electropolymerizers, i.e., citrate and the mixture of citrate and potassium nitrate as sensing elements. Different electropolymerizers lead result in different amount of negative charge on PEDOT electrode, which leads to different adsorption capacity for positive charge amino acids and different repulsion capacity for negative charge amino acids, bringing about obvious changes in differential pulse voltammetry (DPV) current. The five amino acids were accurately identified by linear discriminant analysis (LDA), and the electrochemical sensor array was successfully applied in the differential detection of amino acids in milk.

Construction of a colorimetric sensor array based on the coupling reaction to identify phenols.

Phenols are harmful to the human body and the environment. Since there are a variety of phenols in actual samples, this requires a sensor which possesses the ability to simultaneously distinguish them. Herein, we report a colorimetric sensor array, which uses two nanozymes (Fe-N-C nanozymes and Cu-N-C nanozymes) as electronic tongues for fingerprint identification of six phenols (2,4,6-trichlorophenol (2,4,6-Tri), 4-nitrophenol (P-np), phenol (Phe), 3-chlorophenol (3-CP), 4-chlorophenol (4-CP), and o-nitrophenol (O-np)) in the environment. Nanozymes catalyzed the reaction of hydrogen peroxide, different phenols and 4-aminoantipyrine (4-AAP) to produce different color variations. These signal changes as fingerprints encouraged us to develop a pattern recognition method for the identification of phenols by linear discriminant analysis (LDA). The six phenols at 50 nM have their own response patterns, respectively. Surprisingly, this sensor array had distinguished the six phenols in actual samples successfully.

A colorimetric sensor array for rapid discrimination of edible oil species based on a halogen ion exchange reaction between CsPbBr3 and iodide.

Peroxides in edible oils, whose amounts are measured using the peroxide value, are closely related to human health. Long-term consumption of edible oils with high peroxide values can lead to a variety of human diseases, which highlights the significance of examining oil types and their corresponding peroxide values. For identifying a wide range of edible oils, we established a colorimetric sensor array based on the halogen ion exchange between CsPbBr3 and two iodides (octadecylammonium iodide (ODAI) and ZnI2). Different kinds of edible oils contain distinct peroxidic substances that have the distinct ability to oxidize iodides. After specific types of edible oils react with excess iodides (ODAI and ZnI2), different amounts of residual iodides are left for further halogen exchange with CsPbBr3, resulting in various colorimetric responses, measured in RGB (red/green/blue) values, under fluorescent light. Based on RGB pattern analysis as fingerprints using two anion exchangers (ODAI and ZnI2), our proposed colorimetric sensor array was proved by linear discriminant analysis (LDA) to have an ability to accurately distinguish edible oils at a minimal volumetric concentration of 6.67% in seven real samples.

Study on the degradation of tetracycline in wastewater by micro-nano bubbles activated hydrogen peroxide.

Recently, the micro-nano bubble (MB) technology has attracted people's attention due to its special advantages. Here, we carried out the technology of combining MB and hydrogen peroxide (MB/H2O2) to achieve efficient degradation of tetracycline wastewater. The effect of MB/H2O2 technology on the degradation efficiency of tetracycline was deeply analysed by investigating the reaction time, H2O2 dosage, pH and MB inlet flow. The results showed that the degradation rate of tetracycline hydrochloride by MB/H2O2 technology can reach 92.43%, which is 9.44 and 3.94 times that of MB and H2O2 alone. Through electron spin resonance (ESR) analysis and free radical quenching experiments, a possible mechanism for MB/H2O2 technology to efficiently degrade TC was proposed. In the MB/H2O2 system, the high temperature and high pressure environment generated when MB ruptures can activate H2O2 to obtain a higher number of active oxygen species. •OH is the main reactive oxygen radical in the process of MB/H2O2 degradation of TC, followed by HO2•/•O2-. In addition, the possible intermediate products of the oxidation TC process were identified by HPLC-MS technology. Under the action of •OH and HO2•/•O2- free radicals, TC molecules undergo demethylation and hydroxylation, ring-opening reactions, isomerization, deethylation, deacylation, deamination and dehydration reactions to generate intermediate products and finally convert them into CO2 and H2O. The development of MB/H2O2 technology can potentially be used to efficiently remove TC substances in the water environment and provide a new method for water purification.