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Chemical recycling is a promising approach to reduce plastic pollution. Timely and accurate size analysis of produced nanoplastics is necessary to monitor the process and assess the quality of chemical recycling. In this work, a sandwich-type microelectrode sensor was developed for the size assessment of nanoplastics. ß-Mercaptoethylamine was modified on the microelectrode to enhance its surface positive charge density. Polystyrene (PS) nanoplastics were captured on the sensor through electrostatic interactions. Ferrocene was used as an electrochemical beacon and attached to PS via hydrophobic interactions. The results show a nonlinear dependence of the sensor's current response on the PS particle size. The size resolving ability of the microelectrode is mainly attributed to the small size of the electrode and the resulting attenuation of the electric field strength. For mixed samples with different particle sizes, this method can provide accurate average particle sizes. Through an effective pretreatment process, the method can be applied to PS nanoplastics with different surface properties, ensuring its application in evaluating different chemical recycling methods.
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Major depressive disorder (MDD) is a prevalent brain disorder affecting more than 2% of the world's population. Due to the lack of well-specific biomarkers, it is difficult to distinguish MDD from other diseases with similar clinical symptoms (such as Alzheimer's disease and cerebral thrombosis). In this work, we provided a strategy to address this issue by constructing a combinatorial biomarker of serum glial fibrillary acidic protein (GFAP) and neurofilament light chain (NFL). To achieve the convenient and sensitive detection of two proteins, we developed an electrochemical immunosandwich sensor using two metal-ion-doped carbon dots (Pb-CDs and Cu-CDs) as probes for signal output. Each probe contains approximately 300 Pb2+ or 200 Cu2+, providing excellent signal amplification. This method achieved detection limits of 0.3 pg mL-1 for GFAP and 0.2 pg mL-1 for NFL, lower than most of the reported detection limits. Analysis of real serum samples showed that the concentration ratio of GFAP to NFL, which is associated with the relative degree of brain inflammation and neurodegeneration, is suitable for not only distinguishing MDD from healthy individuals but also specifically distinguishing MDD from Alzheimer's disease and cerebral thrombosis. The good specificity gives the combinatorial GFAP/NFL biomarker broad application prospects in the screening, diagnosis, and treatment of MDD.
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Doença de Alzheimer , Transtorno Depressivo Maior , Trombose Intracraniana , Humanos , Transtorno Depressivo Maior/diagnóstico , Doença de Alzheimer/diagnóstico , Proteína Glial Fibrilar Ácida , Filamentos Intermediários , Chumbo , BiomarcadoresRESUMO
The configuration elucidation of organic molecules continues to pose significant challenges in studies involving stereochemistry. Nuclear magnetic resonance (NMR) techniques are powerful for obtaining such structural information. Anisotropic NMR techniques, such as measurement of residual dipolar couplings (RDCs) and residual chemical shift anisotropies (RCSAs), complementing isotropic NMR parameters, provide relative configuration information. RCSAs provide valuable structural information, especially for nonprotonated carbons, yet have been severely underutilized due to the lack of an easily operational alignment medium capable of rapid transition from anisotropic to isotropic environments, especially in aqueous conditions. In this study, an oligopeptide-based alignment media (FK)4 is presented for RCSA measurements. Temperature variation manipulates the assembly of (FK)4, yielding tunable anisotropic and isotropic phases without the requirement of any special devices or time-consuming correction procedures during data analysis. Decent observed ΔΔRCSA values from sp3 carbons benefit the utilization of RCSA measurements in the structural elucidation of organic molecules highly composed with sp3 carbons. Moreover, the (FK)4 alignment medium is applicable for both RDC and RCSA measurements in one sample, further advancing the configuration analysis of molecules of interest.
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Root-knot nematodes (RKNs) infect host plants and obtain nutrients such as sugars for their own development. Therefore, inhibiting the nutrient supply to RKNs may be an effective method for alleviating root-knot nematode disease. At present, the pathway by which sucrose is unloaded from the phloem cells to giant cells (GCs) in root galls and which genes related to sugar metabolism and transport play key roles in this process are unclear. In this study, we found that sugars could be unloaded into GCs only from neighboring phloem cells through the apoplastic pathway. With the development of galls, the contents of sucrose, fructose and glucose in the galls and adjacent tissue increased gradually. SUT1, SUT2, SWEET7a, STP10, SUS3 and SPS1 may provide sugar sources for GCs, while STP1, STP2 and STP12 may transport more sugar to phloem parenchyma cells. At the early stage of Meloidogyne incognita infestation, the sucrose content in tomato roots and leaves increased, while the glucose and fructose contents decreased. SWEET7a, SPS1, INV-INH1, INV-INH2, SUS1 and SUS3 likely play key roles in root sugar delivery. These results elucidated the pathway of sugar unloading in tomato galls and provided an important theoretical reference for eliminating the sugar source of RKNs and preventing root-knot nematode disease.
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Raízes de Plantas , Tumores de Planta , Solanum lycopersicum , Tylenchoidea , Tylenchoidea/fisiologia , Animais , Solanum lycopersicum/parasitologia , Solanum lycopersicum/metabolismo , Raízes de Plantas/parasitologia , Raízes de Plantas/metabolismo , Tumores de Planta/parasitologia , Doenças das Plantas/parasitologia , Sacarose/metabolismo , Açúcares/metabolismo , Metabolismo dos CarboidratosRESUMO
Single-component electrocatalysts generally lead to unbalanced adsorption of OH- and urea during urea oxidation reaction (UOR), thus obtaining low activity and selectivity especially when oxygen evolution reaction (OER) competes at high potentials (>1.5 V). Herein, a cross-alignment strategy of in situ vertically growing Ni(OH)2 nanosheets on 2D semiconductor g-C3N4 is reported to form a hetero-structured electrocatalyst. Various spectroscopy measurements including in situ experiments indicate the existence of enhanced internal electric field at the interfaces of vertical Ni(OH)2 and g-C3N4 nanosheets, favorable for balancing adsorption of reaction intermediates. This heterojunction electrocatalyst shows high-selectivity UOR compared to pure Ni(OH)2, even at high potentials (>1.5 V) and large current density. The computational results show the vertical heterojunction could steer the internal electric field to increase the adsorption of urea, thus efficiently avoiding poisoning of strongly adsorbed OH- on active sites. A membrane electrode assembly (MEA)-based electrolyzer with the heterojunction anode could operate at an industrial-level current density of 200 mA cm-2. This work paves an avenue for designing high-performance electrocatalysts by vertical cross-alignments of active components.
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It is widely acknowledged that infectious diseases have wrought immense havoc on human society, being regarded as adversaries from which humanity cannot elude. In recent years, the advancement of Artificial Intelligence (AI) technology has ushered in a revolutionary era in the realm of infectious disease prevention and control. This evolution encompasses early warning of outbreaks, contact tracing, infection diagnosis, drug discovery, and the facilitation of drug design, alongside other facets of epidemic management. This article presents an overview of the utilization of AI systems in the field of infectious diseases, with a specific focus on their role during the COVID-19 pandemic. The article also highlights the contemporary challenges that AI confronts within this domain and posits strategies for their mitigation. There exists an imperative to further harness the potential applications of AI across multiple domains to augment its capacity in effectively addressing future disease outbreaks.
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COVID-19 , Doenças Transmissíveis , Humanos , Inteligência Artificial , Pandemias , Busca de Comunicante , Doenças Transmissíveis/diagnósticoRESUMO
Calculating the thermal rate constants of elementary combustion reactions is of great importance in theoretical chemistry. Machine learning has become a powerful, data-driven method for predicting rate constants nowadays. Recently, the molecular similarity combined with the topological indices were proposed to represent the hydrogen abstraction reactions of alkane [J. Chem. Inf. Model. 2023, 63, 5097-5106], which are, however, not applicable to alkane cracking reactions, another important class of combustion reactions, due to the cleavage of the C-C bond. In this work, a new feature selection scheme is proposed to describe both bimolecular and unimolecular cracking reactions. Molecular descriptors are elaborately selected individually for both reactants and products from those generated by the open-source software RDKit. Machine learning models combined with these molecular descriptors are proven to have the ability to accurately predict rate constants of both the hydrogen abstraction reactions of alkanes by CH3 and the alkane cracking reactions. The average deviation of the XGB-FNN model for prediction is around 60% for the hydrogen abstraction reactions of alkanes and 100% for the alkane cracking reactions. It is expected that the descriptors proposed in this work can be applied to build machine learning models for other reactions.
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BACKGROUND The evidence on use of supplementary titanium cable cerclage (TCC) in treating femoral subtrochanteric fractures (FSF) remains scarce. Therefore, this study aimed to investigate the potential therapeutic effects for FSF patients using TCC. MATERIAL AND METHODS A retrospective study of 68 FSF patients treated by a long intramedullary (IM) nailing with (Observation group, n=41) or without (Control group, n=27) TCC was conducted from January 2020 to December 2021. The primary outcome measure was time to postoperative full weight-bearing. Secondary outcome measures were operation time, intraoperative blood loss, number of blood transfusions needed, varus angle loss, excellent and good rate of fracture reduction, Harris score, and survival rate. RESULTS Patients were followed up for 13 to 36 months. The excellent and good rate of fracture reduction was 100% in the Observation group versus 92.6% in the Control group (P=0.013), and the varus angle loss and time to postoperative full weight-bearing in the Observation group were significantly less than in the Control group (P<0.05). The intraoperative blood loss in the Observation group was significantly higher than in the Control group (P<0.001). No differences were noted between groups for Harris scores and survival rates at last follow-up. CONCLUSIONS TCC fixation combined with IM nailing can improve the excellent and good rate of fracture reduction and reduce varus angle loss, as well as shorten the time to full weight-bearing and promote early functional exercise, which offers an effective treatment option for FSF patients who have failed closed reduction.
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Pinos Ortopédicos , Fixação Intramedular de Fraturas , Fraturas do Quadril , Titânio , Humanos , Feminino , Estudos Retrospectivos , Masculino , Fixação Intramedular de Fraturas/métodos , Idoso , Fraturas do Quadril/cirurgia , Resultado do Tratamento , Pessoa de Meia-Idade , Fraturas do Fêmur/cirurgia , Idoso de 80 Anos ou mais , Suporte de CargaRESUMO
BACKGROUND It is unclear whether preoperative thyroid-stimulating hormone (TSH) level is correlated with long-term mortality in the elderly after hip fracture surgery. We aimed to assess the association between TSH levels and 3-year mortality in these patients. MATERIAL AND METHODS We enrolled patients aged 65 and above who had hip fracture surgery and thyroid function tests upon admission from 2018 to 2019. Patients were categorized based on TSH median value, quartiles, or thyroid function status. The median follow-up time was 3.1 years. Cox proportional hazards models were used to examine the correlation between TSH levels and mortality, adjusting for covariates. RESULTS Out of 799 eligible patients, 92.7% (741/799) completed the follow-up, with 20.6% (153/741) of those having died by the end of the follow-up. No statistically significant differences in mortality risks were found when stratified by TSH median value (HR 0.88, 95% CI 0.64-1.22, P=0.448) or quartiles (HR ranging from 0.90 to 1.13, P>0.05). Similarly, when categorized based on admission thyroid function status, patients who presented with hypothyroidism, subclinical hypothyroidism, hyperthyroidism, and subclinical hyperthyroidism upon admission did not demonstrate a statistically significant difference in mortality risk compared to those who were considered euthyroid (HR 1.34, 95% CI 0.72-2.49, P=0.359; HR 0.77, 95% CI 0.38-1.60, P=0.489; HR 1.15, 95% CI 0.16-8.30, P=0.890; HR 1.07, 95% CI 0.34-3.38, P=0.913, respectively). CONCLUSIONS Admission TSH is not significantly associated with 3-year mortality in geriatric patients after hip fracture surgery.
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Fraturas do Quadril , Tireotropina , Humanos , Fraturas do Quadril/mortalidade , Fraturas do Quadril/cirurgia , Fraturas do Quadril/sangue , Idoso , Masculino , Tireotropina/sangue , Feminino , Estudos Prospectivos , Idoso de 80 Anos ou mais , Testes de Função Tireóidea , Modelos de Riscos Proporcionais , Período Pré-Operatório , Fatores de Risco , Hipotireoidismo/sangue , Hipotireoidismo/mortalidade , Hipertireoidismo/sangue , Hipertireoidismo/mortalidadeRESUMO
OBJECTIVE: Osteoarthritis (OA) is characterized by progressive cartilage degeneration and absence of curative therapies. Therefore, more efficient therapies are compellingly needed. Both mesenchymal stem cells (MSCs)-derived extracellular vesicles (EVs) and Icariin (ICA) are promising for repair of cartilage defect. This study proposes that ICA may be combined to potentiate the cartilage repair capacity of MSC-EVs. MATERIALS AND METHODS: MSC-EVs were isolated from sodium alginate (SA) and hyaluronic acid (HA) composite hydrogel (SA-HA) cell spheroid culture. EVs and ICA were combined in SA-HA hydrogel to test therapeutic efficacy on cartilage defect in vivo. RESULTS: EVs and ICA were synergistic for promoting both proliferation and migration of MSCs and inflammatory chondrocytes. The combination therapy led to strikingly enhanced repair on cartilage defect in rats, with mechanisms involved in the concomitant modulation of both cartilage degradation and synthesis makers. CONCLUSION: The MSC-EVs-ICA/SA-HA hydrogel potentially constitutes a novel therapy for cartilage defect in OA.
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Vesículas Extracelulares , Células-Tronco Mesenquimais , Osteoartrite , Animais , Ratos , Hidrogéis/farmacologia , Ácido Hialurônico/farmacologia , Ácido Hialurônico/metabolismo , Cartilagem , Condrócitos/metabolismo , Osteoartrite/tratamento farmacológico , Regeneração , Vesículas Extracelulares/metabolismoRESUMO
The detection of botulinum neurotoxin A (BoNT/A) endopeptidase activity by pregnancy test paper based on human chorionic gonadotropin (hCG)-functionalized peptide-modified magnetic nanoparticles (MNs) is described for the first time. HCG-functionalized SNAP-25 peptide substrate with hydrolysis recognition sites was optimally designed. HCG can be recognized by pregnancy test strips. BoNT/A light chain (BoNT-LcA) is the central part of the endopeptidase function in holotoxin, which can specifically hydrolyze SNAP-25 peptide to release the hCG-peptide probe, and the hCG-peptide probe released can be quantitatively detected by pregnancy test strips, achieving indirect determination of BoNT/A. By quantifying the T-line color intensity of test strips, the visual detection limit for BoNT-LcA is 12.5 pg/mL, and the linear range of detection for BoNT-LcA and BoNT/A holotoxin was 100 pg/mL to 1 ng/mL and 25 to 250 ng/mL. The ability of the method to quantify BoNT/A was validated in human serum samples. This method shows the potential for sensitive detecting BoNT/A and has prospects for the diagnosis and prognosis of clinical botulism.
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Toxinas Botulínicas Tipo A , Glicosídeos , Nanopartículas de Magnetita , Testes de Gravidez , Triterpenos , Humanos , Feminino , Gravidez , Endopeptidases , Gonadotropina CoriônicaRESUMO
An ultra-sensitive photoelectrochemical (PEC) sensor based on perovskite composite was developed for the determination of alkaline phosphatase (ALP) in human serum. In contrast to CsPbBr3 or Y6 that generated anodic current, the heterojunction of CsPbBr3/Y6 promoted photocarriers to separate and generated cathodic photocurrent. Ascorbic acid (AA) was produced by ALP hydrolyzing L-ascorbic acid 2-phosphate trisodium salt (AAP), which can combine with the holes on the photoelectrode surface, accelerating the transmission of photogenerated carriers, leading to enhanced photocurrent intensity. Thus, the enhancement of PEC current was linked to ALP activity. The PEC sensor exhibits good sensitivity for detection of ALP owing to the unique photoelectric properties of the CsPbBr3/Y6 heterojunction. The detection limit of the sensor was 0.012 U·L-1 with a linear dynamic range of 0.02-2000 U·L-1. Therefore, this PEC sensing platform shows great potential for the development of different PEC sensors.
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Fosfatase Alcalina , Ácido Ascórbico , Técnicas Eletroquímicas , Eletrodos , Limite de Detecção , Óxidos , Processos Fotoquímicos , Titânio , Fosfatase Alcalina/química , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo , Humanos , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Ácido Ascórbico/química , Ácido Ascórbico/sangue , Ácido Ascórbico/análogos & derivados , Titânio/química , Óxidos/química , Compostos de Cálcio/química , Técnicas Biossensoriais/métodosRESUMO
OBJECT: This study aimed to investigate the changes in the translucency and color of four different multi-layered zirconia materials when the sintering temperature were inaccurate. MATERIALS AND METHODS: Two hundred zirconia samples (11 × 11 × 1.0 mm) of four multi-layered zirconia, Upcera TT-GT (UG), Upcera TT-ML (UM), Cercon xt ML (CX), and Lava Esthetic (LE), were divided into five subgroups according to the sintering temperature: L1 (5% lower temperature), L2 (2.5% lower temperature), R (recommended sintering temperature), H2 (2.5% higher temperature), H1 (5% higher temperature). After sintering, color coordinates were measured. Then the translucency parameter (TP) values, and the color differences (between the inaccurate sintering temperature and the recommended temperature) of each zirconia specimen were calculated. Statistical analysis was performed by using three-way ANOVA tests, the one-way ANOVA, and Tukey's post hoc test. RESULTS: Three-way ANOVA results showed that material type, sintering temperature, specimen section, and their interactions significantly influenced the TP values (except for the interactions of specimen section and sintering temperature) (P < .05). TP values of zirconia specimens were significantly different in the inaccurate sintering temperatures (P < .05), except for the cervical and body sections of UG group (P > .05). Compared with recommended sintering temperature, higher sintering temperature caused higher TP values for CX, but lower for LE. Three-way ANOVA results showed that material type, sintering temperature, and their interactions significantly influenced the ∆E00 values (P < .05). There were no significant differences in ∆E00 values of UM and CX groups at different inaccurate sintering temperatures, and were clinical imperception (except for UM-L1) (∆E00 < 1.25). ∆E00 values of all zirconia specimens showed clinically acceptable (∆E00 < 2.23). CONCLUSION: The deviations in sintering temperature significantly influenced the translucency and color of tested multi-layered zirconia. The trends of translucency in the multi-layered zirconia depended on material type and the color changes of all zirconia materials were clinically acceptable at inaccurate sintering temperatures.
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Cerâmica , Zircônio , Humanos , Temperatura , Teste de Materiais , Propriedades de Superfície , CorRESUMO
The development of high-purity and high-energy-density green hydrogen through water electrolysis holds immense promise, but issues such as electrocatalyst costs and power consumption have hampered its practical application. In this study, we present a promising solution to these challenges through the use of a high-performance bifunctional electrocatalyst for energy-efficient hydrogen production via coupled hydrazine degradation. The biphasic metal nitrides with highly lattice-matched structures are deliberately constructed, forming an enhanced local electric field between the electron-rich Ni3N and electron-deficient Co3N. Additionally, Mn is introduced as an electric field engine to further activate electron redistribution. Our Mn@Ni3N-Co3N/NF bifunctional electrocatalyst achieves industrial-grade current densities of 500â mA cm-2 at 0.49â V without degradation, saving at least 53.3 % energy consumption compared to conventional alkaline water electrolysis. This work will stimulate the further development of metal nitride electrocatalysts and also provide new perspectives on low-cost hydrogen production and environmental protection.
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Three new nitrides La3MN5 (M=Cr, Mn, and Mo) have been synthesized using a high pressure azide route. These are the first examples of ternary Cs3CoCl5-type nitrides, and show that this (MN4)NLa3 antiperovskite structure type may be used to stabilise high oxidation-state transition metals in tetrahedral molecular [MN4]n- nitridometallate anions. Magnetic measurements confirm that Cr and Mo are in the M6+ state, but the M=Mn phase has an anomalously small paramagnetic moment and large cell volume. Neutron powder diffraction data are fitted using an anion-excess La3MnN5.30 model (space group I4/mcm, a=6.81587(9)â Å and c=11.22664(18)â Å at 200â K) in which Mn is close to the +7 state. Excess-anion incorporation into Cs3CoCl5-type materials has not been previously reported, and this or other substitution mechanisms may enable many other high oxidation state transition metal nitrides to be prepared.
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The efficient conversion and storage of solar energy for chemical fuel production presents a challenge in sustainable energy technologies. Metal nitrides (MNs) possess unique structures that make them multi-functional catalysts for water splitting. However, the thermodynamic instability of MNs often results in the formation of surface oxide layers and ambiguous reaction mechanisms. Herein, we present on the photo-induced reconstruction of a Mo-rich@Co-rich bi-layer on ternary cobalt-molybdenum nitride (Co3 Mo3 N) surfaces, resulting in improved effectiveness for solar water splitting. During a photo-oxidation process, the uniform initial surface oxide layer is reconstructed into an amorphous Co-rich oxide surface layer and a subsurface Mo-N layer. The Co-rich outer layer provides active sites for photocatalytic oxygen evolution reaction (POER), while the Mo-rich sublayer promotes charge transfer and enhances the oxidation resistance of Co3 Mo3 N. Additionally, the surface reconstruction yields a shortened Co-Mo bond length, weakening the adsorption of hydrogen and resulting in improved performance for both photocatalytic hydrogen evolution reaction (PHER) and POER. This work provides insight into the surface structure-to-activity relationships of MNs in solar energy conversion, and is expected to have significant implications for the design of metal nitride-based catalysts in sustainable energy technologies.
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As a sustainable valorization route, electrochemical glycerol oxidation reaction (GOR) involves in formation of key OH* and selective adsorption/cleavage of C-C(O) intermediates with multi-step electron transfer, thus suffering from high potential and poor formate selectivity for most non-noble-metal-based electrocatalysts. So, it remains challenging to understand the structure-property relationship as well as construct synergistic sites to realize high-activity and high-selectivity GOR. Herein, we successfully achieve dual-high performance with low potentials and superior formate selectivity for GOR by forming synergistic Lewis and Brønsted acid sites in Ni-alloyed Co-based spinel. The optimized NiCo oxide solid-acid electrocatalyst exhibits low reaction potential (1.219â V@10â mA/cm2) and high formate selectivity (94.0 %) toward GOR. In situ electrochemical impedance spectroscopy and pH-dependence measurements show that the Lewis acid centers could accelerate OH* production, while the Brønsted acid centers are proved to facilitate high-selectivity formation of formate. Theoretical calculations reveal that NiCo alloyed oxide shows appropriate d-band center, thus balancing adsorption/desorption of C-O intermediates. This study provides new insights into rationally designing solid-acid electrocatalysts for biomass electro-upcycling.
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ATP (adenosine triphosphate) is a vital energy source for living organisms, and its biosynthesis and precise concentration regulation often depend on macromolecular machinery composed of protein complexes or complicated multidomain proteins. We have identified a single-domain protein HK853CA derived from bacterial histidine kinases (HK) that can catalyze ATP synthesis efficiently. Here, we explored the reaction mechanism and multiple factors that influence this catalysis through a combination of experimental techniques and molecular simulations. Moreover, we optimized its enzymatic activity and applied it as an ATP replenishment machinery to other ATP-dependent systems. Our results broaden the understanding of ATP biosynthesis and show that the single CA domain can be applied as a new biomolecular catalyst used for ATP supply.
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Bactérias , Proteínas de Bactérias , Histidina Quinase/metabolismo , Proteínas de Bactérias/metabolismo , Bactérias/metabolismo , Trifosfato de Adenosina/metabolismo , CatáliseRESUMO
Strategies for discovery of high-performance electrocatalysts are important to advance clean energy technologies. Metastable phases such as low temperature or interfacial structures that are difficult to access in bulk may offer such catalytically active surfaces. We report here that the suboxide Zr3O, which is formed at Zr-ZrO2 interfaces but does not appear in the experimental Zr-O phase diagram exhibits outstanding oxygen reduction reaction (ORR) performance surpassing that of benchmark Pt/C and most transition metal-based catalysts. Addition of Fe3C nanoparticles to give a Zr-Zr3O-Fe3C/NC catalyst (NC=nitrogen-doped carbon) gives a half-wave potential (E1/2) of 0.914â V, outperforming Pt/C and showing only a 3â mV decrease after 20,000 electrochemical cycles. A zinc-air battery (ZAB) using this cathode material has a high power density of 241.1â mW cm-2 and remains stable for over 50â days of continuous cycling, demonstrating potential for practical applications. Zr3O demonstrates that interfacial or other phases that are difficult to stabilize may offer new directions for the discovery of high-performance electrocatalysts.
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Graphene@MXene composite nanomaterials were utilized to construct an electrochemical sensor for alanine aminotransferase (ALT) detection. The combination of graphene nanosheets with MXene avoids the self-stacking of MXene and graphene, and broadens the charge transfer channel. In addition, the composite nanomaterial provides increased loading sites for pyruvate oxidase. The principle of ALT detection is a two-step enzymatic reaction. L-Alanine was initially transferred to pyruvate catalyzed by ALT. The formed pyruvate was then oxidized by pyruvate oxidase, generating H2O2. Through the detection of the generated H2O2, ALT activity was measured. The linear range of the sensor to ALT was from 5 to 400 U·L-1 with a detection limit of 0.16 U·L-1 (S/N = 3). For real sample analysis, the spiked recovery test results of ALT in serum samples were between 96.89 and 103.93% with RSD < 5%, confirming the reliability of the sensor testing results and potential clinical application of the sensor.