1.Comparison of Wild and Cultivated Alpiniae Oxyphyllae Fructus Based on Traditional Quality Evaluation
Fengfan WANG ; Yajie XIANG ; Jian FENG ; Wencheng HOU ; Wenlan LI ; Yangyang LIU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(5):235-244
ObjectiveTo compare the differences between wild Alpiniae Oxyphyllae Fructus(WAOF) and cultivated Alpiniae Oxyphyllae Fructus(CAOF) through a traditional quality evaluation system for medicinal materials. MethodsA total of 10 batches of WAOF and 12 batches of CAOF samples were collected from various regions of Hainan province. Relevant analytical methods from the 2020 edition of the Pharmacopoeia of the People's Republic of China were employed to observe the characteristics of WAOF and CAOF, followed by microscopic identification, thin-layer chromatography(TLC) identification, moisture content(toluene method), total ash, acid-insoluble ash, water-soluble and alcohol-soluble extracts(hot dipping method), water-soluble protein, total polysaccharides and total flavonoids(ultraviolet spectrophotometry), and volatile oil content(method A under general rule 2204). The contents of five active components(protocatechuic acid, chrysin, kaempferol, tectochrysin and nootkatone) were quantified using ultra-performance liquid chromatography(UPLC), and the antioxidant activity was evaluated. Building upon traditional quality evaluation of AOF, quantitative measurements were conducted on its appearance traits including diameter, length, plumpness(diameter/length ratio), and color. Canonical correlation analysis was performed using SPSS 26.0 to explore relationships between appearance traits and intrinsic quality. ResultsNo significant differences were observed between WAOF and CAOF in microscopic observation, TLC identification, moisture content, protocatechuic acid content, kaempferol content, odor, or antioxidant activity measured by 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS) method. WAOF exhibited significantly higher levels in water-soluble extracts, alcohol-soluble extracts, total polysaccharide content, water-soluble protein content, 100-grain weight, length, and total color difference(ΔE*ab) compared to CAOF(P<0.01). In contrast, CAOF showed significantly higher levels of total ash, acid-insoluble ash, content of total flavonoids, volatile oil content, chrysin content, tectochrysin content, nootkatone content, diameter, plumpness, lightness(L*), red-green chromaticity(a*), yellow-blue chromaticity(b*), and antioxidant activity measured by 1,1-diphenyl-2-picrylhydrazyl(DPPH) method compared to WAOF(P<0.01). Correlation analysis between 7 phenotypic traits and 8 quality traits revealed that among the phenotypic traits, plumpness, L*, a*, and b* exerted significant influence on intrinsic quality. Among the quality traits, total flavonoids, volatile oils, nootkatone, chrysin, and tectochrysin contributed substantially to intrinsic quality. ConclusionPlumpness, L*, a*, and b* of AOF significantly influence its intrinsic quality, and higher values of these parameters indicate relatively superior intrinsic quality. The comprehensive quality evaluation reveals that CAOF samples collected in this study are superior to their wild counterparts.
2.Polypeptide-based Nanocarriers for Oral Targeted Delivery of CAR Genes to Pancreatic Cancer
Feng XIN ; Jian REN ; Zhao-Zhen LI ; Quan FANG ; Rui-Jing LIANG ; Lan-Lan LIU ; Lin-Tao CAI
Progress in Biochemistry and Biophysics 2026;53(2):431-441
ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.
3.Polypeptide-based Nanocarriers for Oral Targeted Delivery of CAR Genes to Pancreatic Cancer
Feng XIN ; Jian REN ; Zhao-Zhen LI ; Quan FANG ; Rui-Jing LIANG ; Lan-Lan LIU ; Lin-Tao CAI
Progress in Biochemistry and Biophysics 2026;53(2):431-441
ObjectivePancreatic ductal adenocarcinoma (PDAC) exhibits a limited response to current treatments due to its dense fibrotic stroma and highly immunosuppressive tumor microenvironment. In recent years, advancements in cellular immunotherapy, particularly chimeric antigen receptor macrophage (CAR-M) therapy, have offered new hope for pancreatic cancer treatment. Although CAR-M therapy demonstrates dual potential in directly killing tumor cells and remodeling the immune microenvironment, it still faces challenges such as complex in vitro preparation processes and low in vivo targeting and delivery efficiency. Therefore, developing strategies for efficient and targeted in vivo delivery of CAR genes has become crucial for overcoming current therapeutic limitations. This study aims to develop an orally administrable nano-gene delivery system for the targeted delivery of CAR genes to pancreatic tumor sites. MethodsCore nano-gene particles (PNP/pCAR) were constructed by loading plasmid DNA encoding CAR (pCAR) with cationic polypeptides (PNP). Subsequently, PNP/pCAR was surface-modified with β-glucan to prepare the targeted nanoparticles (βGlus-PNP/pCAR). The loading efficiency of PNP for pCAR was quantitatively assessed by gel retardation assay. The particle size, Zeta potential, morphology, and storage stability of PNP/pCAR were characterized using a Malvern particle size analyzer and transmission electron microscopy. At the cellular level, RAW 264.7 macrophages were selected. The cytotoxicity of PNP/pCAR was evaluated using the CCK-8 assay. The cellular uptake efficiency and lysosomal escape ability of the nanoparticles were assessed via flow cytometry and confocal microscopy. Transfection efficiency was quantitatively evaluated by detecting the expression of the reporter gene GFP using flow cytometry. At the in vivo level, an orthotopic pancreatic cancer mouse model was established. Cy7-labeled βGlus-PNP/pCAR nanoparticles were administered orally, and the fluorescence distribution in mice was dynamically monitored at 1, 2, 4, 8, and 16 h post-administration using a small animal in vivo imaging system. Forty-eight hours after oral gavage, the mice were euthanized, and pancreatic tumor tissues were collected for further analysis of intratumoral fluorescence signals using the imaging system. Additionally, βGlus-PNP/pCAR-GFP nanoparticles loaded with the reporter gene (GFP) were administered orally. Forty-eight hours post-administration, pancreatic tumor tissues were harvested to prepare frozen sections, and GFP expression was observed and analyzed under a fluorescence microscope. ResultsThe PNP carrier exhibited a high loading capacity for pCAR. The successfully prepared PNP/pCAR nanoparticles were regular spheres with a hydrodynamic diameter of approximately (120±10) nm and a Zeta potential of about +(6±1) mV. They maintained good structural stability after incubation in PBS buffer for 7 d. Cell experiments demonstrated that PNP/pCAR exhibited no significant cytotoxicity in RAW 264.7 cells while being efficiently internalized and effectively escaping lysosomal degradation. The transfection positive rate of PNP/pCAR-GFP in RAW 264.7 cells reached (25±3)%, surpassing that of Lipofectamine 2000-loaded pCAR-GFP (Lipo/pCAR-GFP), which was (20±1)%.In vivo experiments revealed that, compared to unmodified PNP/pCAR, βGlus-PNP/pCAR exhibited strongerin situ pancreatic tumor targeting ability after oral administration. Furthermore, oral administration of βGlus-PNP/pCAR-GFP resulted in significant GFP protein expression detectable within pancreatic tumor tissues. ConclusionThis study successfully constructed and validated an orally administrable, pancreatic cancer-targeting polypeptide-based nano-gene delivery system. It provides an important technological foundation in delivery systems and experimental basis for the subsequent development of in situ CAR-M-based therapeutic strategies for pancreatic cancer.
4.Characteristics of gut microbiota in people with circadian rhythm disruption and its correlation with cognition
Jincheng JIAN ; Wei HE ; Hongfei JIANG ; Yusong GE ; Zhanjie HOU ; Yuanyuan LEI ; Yingjie WANG ; Yunxuan FENG ; Xiaojie FENG ; Bo TANG
Journal of Army Medical University 2025;47(9):980-988
Objective To analyze the diversity and composition of gut microbiota in individuals with circadian rhythm disruption and their correlation with cognition.Methods Night shift workers and regular shift workers were subjected from our hospital during August 2022 and October 2024.The participants with circadian rhythm disorders were assigned into an experimental group(n=24),and those with normal circadian rhythms were into a control group(n=24).Their height,weight,age,gender,body mass index(BMI)and fresh fecal samples were collected,and Montreal Cognitive Assessment(MoCA)and Mini-Mental State Examination(MMSE)were used to evaluate their mental status.Metagenomics,Alpha and Beta diversity analyses,Linear Discriminant Analysis Effect Size(LEfSe),and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis were employed to investigate the diversity and function characteristics of gut microbiota in the participants.Results There were no statistical differences between the 2 groups in baseline data,such as height,weight,gender,age,and BMI(P>0.05).Alpha diversity analysis indicated that no statistical differences were observed in the ACE,Chao1,Shannon,or Simpson indices between the 2 groups,while beta diversity analysis revealed significant differences(P<0.01),suggesting different structure of gut microbiota between them.In the experimental group,the abundance of Faecalibacterium prausnitzii and Agathobacter rectalis was decreased,while that of Escherichia coli and Phocaeicola vulgaratus was increased,with significant differences when compared with the control group(P<0.05).Additionally,KEGG functional analysis showed that the experimental group had obviously higher expression levels in Th17 cell differentiation and the IL-17 signaling pathway than the control group(P<0.05).Agathobacter rectalis and Faecalibacterium prausnitzii were positively correlated with MoCA score and MMSE score(P<0.05,P<0.01).Agathobacter rectalis was negatively correlated with the IL-17 signaling pathway and Th17 cell differentiation.Conclusion Individuals with circadian rhythm disorders have significant changes in the structure and function of gut microbiota when compared to those with normal circadian rhythms.Agathobacter rectalis may be involved in the regulation of the IL-17 signaling pathway and differentiation of Th17 cells,thereby possibly impacting the increases of cognitive score related to circadian rhythm disorders.
5.Prognostic efficacy of pericoronary fat attenuation index and fibrous plaque index in patients with acute coronary syndrome
Cong HUANG ; Feng WEN ; Xinglan WANG ; Chen LIU ; Hongqin LIANG ; Xi YANG ; Chengwei MOU ; Jian WANG
Journal of Army Medical University 2025;47(17):2106-2114
Objective To explore the predictive value of fat attenuation index(FAI)and fibrous plaque index(FPI)for the prognosis of patients with acute coronary syndrome(ACS).Methods A retrospective cohort study was conducted on 334 ACS patients undergoing percutaneous coronary intervention(PCI)in the First Affiliated Hospital of Army Military Medical University and Yongchuan Hospital of Chongqing Medical University from March 2021 to July 2023.All patients received coronary computed tomography angiography(CCTA)to measure FAI and FPI.According to the occurrence of major adverse cardiovascular events(MACE)with 1 year of follow-up,they were divided into MACE group(n=108)and non-MACE group(n=226).The baseline data,CCTA data and results of laboratory tests were collected and compared between the 2 groups.Multivariate logistic regression analysis was used to analyze the relationship of FAI and FPI with the prognosis of ACS patients,and ROC curve was drawn to evaluate its predictive efficiency.Results Among the 334 ACS patients,108(32.34%)experienced MACE.When compared with the non-MACE group,the MACE group exhibited significantly larger proportions of diabetes(72.22%vs 31.86%)and left main coronary artery disease(18.52%vs 7.08%),but lower success rate of operation(79.63%vs 93.81%,P<0.05).Radiologic results showed that the proportion of severe stenosis(20.37%vs 10.62%),FAI(-80.12±6.41 HU vs-72.34±7.09 HU)and FPI(0.58±0.41 vs 0.26±0.12)were obviously increased in the MACE group than the non-MACE group(P<0.05).Laboratory tests indicated that there were statistical differences between the 2 groups in high-density lipoprotein-cholesterol(HDL-C,1.20±0.15 vs 1.09±0.16 mmol/L),miR-126(0.91±0.12 vs 0.96±0.15)and SST2(38.45±5.67 vs 34.30±4.89 ng/mL,P<0.05).Multivariate Logistic regression analysis revealed that FAI(OR=1.200,95%CI:1.136~1.268),FPI(OR=63.157,95%CI:14.126~282.374),moderate stenosis(OR=1.332,95%CI:1.024~1.859),severe stenosis(OR=1.480,95%CI:1.074~2.039),miR-126(OR=0.007,95%CI:0.001~0.077),and sST2(OR=1.192,95%CI:1.113~1.277)were independent predictors of MACE(P<0.05).ROC curve analysis displayed that stenosis degree(AUC=0.622,95%CI:0.561~0.683,P=0.001),FAI(AUC=0.790,95%CI:0.741~0.839,P=0.001)and FPI(AUC=0.700,95%CI:0.638~0.761,P=0.001),miR-126(AUC=0.646,95%CI:0.584~0.707,P=0.001),sST2(AUC=0.700,95%CI:0.638~0.761,P=0.001)had certain predictive values for ACS prognosis.Conclusion Coronary FAI and FPI can be used as independent prognostic indicators of ACS patients,and their numerical changes are closely related to plaque stability and inflammatory state.
6.Gas Chromatography-Infrared Spectroscopy Assisted Gas Chromatography-Mass Spectrometry for Identification of Alkyl Phosphonate Isomers
Mei-Qi ZHAO ; Yu-Long LIU ; Qin LIU ; Wei YOU ; Jian-Feng WU ; Hai-Xia WU ; Jia CHEN ; Jian-Wei XIE
Chinese Journal of Analytical Chemistry 2025;53(2):269-277
Organophosphorus nerve agents are the most threatening chemical warfare agents and terrorist agents.The number of nerve agents and their related chemicals involved in the verification of Chemical Weapon Convention(CWC)exceeds ten million,with the majority being isomers.Accurate structural identification of these chemicals has always been one of the challenges in CWC related verification analysis.In this work,a total of 17 kinds of alkyl phosphonate isomers and structural analogs from 5 groups were designed and synthesized,and then analyzed by gas chromatography-mass spectrometry(GC-MS)and gas chromatography-infrared spectroscopy(GC-FTIR).The spectra of isomers or structural analogs obtained from two techniques as well as the structural information provided therein were compared and analyzed.The results showed that for isomers or structural analogs with similar MS spectra,FTIR spectra could provided more structural fingerprint information of compounds and had advantages in confirming structures.Combined with the excellent separation ability of GC,GC-FTIR can be used to assist GC-MS in the structural confirmation of alkyl phosphates,achieving rapid and accurate identification of isomers or structural analogues.
7.Conformational Epitope Mapping of C-Reactive Protein in Solution by Hydrogen/Deuterium Exchange Mass Spectrometry
Hao-Feng SUN ; Jian-Yi LIU ; Qi ZHANG ; Hui JIAO ; Min ZHOU ; De-Wei SONG
Chinese Journal of Analytical Chemistry 2025;53(4):631-639
C-Reactive protein(CRP)is an important acute-phase response protein,which is widely used in the assessment of inflammation and cardiovascular disease risk,and acts as a pathogenic factor directly involved in the disease process of certain conditions.Therefore,developing immunosuppressants targeting CRP or investigating its pathogenic mechanisms is of significant importance.Most B-cell epitopes are conformational epitopes,and studying conformational epitopes is typically challenging.To date,no methods have been reported for mapping the conformational epitopes of CRP in solution.In this study,a rapid strategy was developed for studying conformational epitopes by combining hydrogen/deuterium exchange mass spectrometry(HDX-MS)with multiparametric prediction of B-cell epitopes and protein secondary structure analysis.This approach was successfully applied to the binding sites and allosteric targets of the 115 kDa full pentameric CRP and the clinically used monoclonal antibody(mAb)5A8.The results showed that the amino acid residues 84-103,138-146,and 165-173 together form the potential conformational epitopes for mAb 5A8 on CRP,while the amino acid residues 21-32 and 175-178 were identified as potential allosteric targets.The discovery of the mAb 5A8 binding sites and allosteric targets was crucial for improving clinical diagnostic capabilities.Experimental results demonstrated that this workflow allowed rapid conformational epitope mapping of CRP under near-physiological conditions,with advantages such as high speed,high sensitivity,and high throughput.
8.Synthesis and Applications of Indole-3-formylhydrazine Modified Pyrene Schiff Base Compound as Copper Ion Fluorescence Probe
Mu-Xi WANG ; Zhen-Yu HUANG ; Xiao-Feng LIN ; Xiao-Lan LEI ; Jian SUN ; Li-Jun MA
Chinese Journal of Analytical Chemistry 2025;53(7):1108-1117
In this work,a fluorescent probe PIN was synthesized using indole-3-carbohydrazide and pyrenecarboxaldehyde as raw materials.PIN showed weak fluorescence emission in aqueous solution with acetonitrile volume fraction of 70%.However,when Cu2+was added to this aqueous solution of PIN,a new fluorescence emission peak appeared at 495 nm,and the intensity of this peak gradually increased with the increase of concentration of Cu2+,and also caused a significant change in the fluorescence color of the solution.In contrast,the addition of 15 kinds of other common metal ions did not cause such change.The detection limit of PIN for Cu2+was 78.7 nmol/L,which was much lower than the maximum permitting level of Cu2+in drinking water in hygienic standard for drinking water in China.Therefore,PIN was a highly selective and sensitive fluorescence-enhanced probe for Cu2+.Meanwhile,the addition of Cu2+could also cause a new absorption peak at 440 nm in the ultraviolet-visible absorption spectrum of the aqueous solution of PIN,and meanwhile the colorless PIN solution changed into yellow,exhibiting the performance of PIN as a colorimetric probe for Cu2+.By fitting with the Levenberg-Marquardt algorithm equation,the binding ratio of PIN to Cu2+was 2:1,and the binding constant was 3.42×1012 L2/mol2.In addition,the binding mode of PIN with Cu2+was explored by using proton nuclear magnetic resonance(1H NMR)titration experiments and density functional theory simulations.The results showed that the addition of Cu2+could cause the aggregation of PIN molecules to form excimers,thus showing highly selective recognition.Finally,PIN was made into a simple test strip,which could achieve rapid and convenient fluorescence detection of Cu2+in actual water samples.
9.Research on Targeted Screening of Diflorasone Components in Health Products Using Feature Ion Guided Strategy Combined with High-Resolution Mass Spectrometry
Shuo-Jun OU ; Yin-Yin LIN ; Hai-Tao ZHANG ; Jian-Bin CEN ; Zhi-Yuan WANG ; Xin-Dong GUO ; Jia-Jun ZHANG ; Zhi-Sen LIANG ; Guang-Feng ZENG
Chinese Journal of Analytical Chemistry 2025;53(8):1320-1330,中插88-中插92
A method for determination and targeted screening of diflorasone components in health products using ultra performance liquid chromatography-quadrupole time of flight mass spectrometry(UPLC-Q-TOF/MS)was established.Four representative diflorasone and esters(diflorasone,diflorasone diacetate,diflorasone-17-propionate,and diflorasone-21-propionate)were selected to optimize the pretreatment conditions,and 10 mL of extraction solvent dosage,15 min of extraction time and 5 g of salting-out agent as the optimal conditions were selected by response surface methodology.The results showed that the four analytes exhibited good linearity within the concentration range of 2.0?100 μg/L with the chromatographic peak area,and the correlation coefficients(R2)were all greater than 0.9990,while the results of recovery and relative standard deviation could satisfy the requirements of determination.The common characteristic ions of diflorasone and esters werem/z121 andm/z335,and their specific structures were obtained by analyzing the cleavage pathway based on the optimized determination conditions.A targeted screening method for other esters of diflorasone based on characteristic ions guidance strategy was established.This method had many advantages such as high efficiency,high sensitivity and good reproducibility,and could be used for targeted screening of diflorasone and esters in health products.The developed characteristic ion guided strategy could be employed to construct mass spectral databases for various glucocorticoids,enabling comprehensive targeted screening across a broad range of compounds.
10.Sensitive Detection of Nitrofurazone by Electrochemical Sensor Based on Platinum Nanoparticles Functionalized Zeolitic Imidazolate Frameworks-derived Porous Carbon and Carbon Nanotubes
Tong CHANG ; Feng-Lin ZHANG ; Mei-Jie GUO ; Yi-Yan BAI ; Jian-Fang QIN ; Hai-Ying YANG
Chinese Journal of Analytical Chemistry 2025;53(11):1908-1920,中插49-中插52
Nitrofurazone(NFZ)is an antibiotic that is used as a veterinary drug in aquaculture.NFZ abuse can lead to a series of environmental and health issues,making it crucial to establish a rapid and highly sensitive method for NFZ detection.In this study,platinum nanoparticle(PtNPs)-loaded zeolitic imidazolate framework(ZIF-8)was used as a precursor,and PtNPs functionalized nitrogen doped porous carbon(NC)was obtained through pyrolysis.Pt@NC was combined with multi-walled carbon nanotubes(MWCNTs)and cast onto a glassy carbon electrode(GCE)surface to construct an electroch-emical sensor.Electrochemical tests revealed that Pt@NC/WCNT/GCE exhibited an electrochemical active area of 0.066 cm2 and a heterogeneous electron transfer rate constant(k0)of 2.03×10-3 cm/s,which were higher than other materials.Compared with the electrodes modified by other materials,the NFZ generated the highest peak current of irreversible reduction peak on the Pt@NC/WCNT/GCE electrode.In comparison with Pt@ZIF-8/WCNT/GCE,after pyrolysis and carbonization treatment,the reduction current of NFZ increased by 2.19 times,and the reduction peak potential shifted positively by 19 mV simultaneously.When compared with NC/WCNT/GCE,the PtNPs in the composite material enhanced the NFZ current by 4.25 times.Additionally,the experimental conditions for detecting NFZ using the sensor were optimized,including the carbonization temperature of Pt@ZIF-8,ratio of Pt@NC to CNT,loading amount of the modified material,and electrolyte pH.Under the optimized conditions,the sensor demonstrated a linear detection range for NFZ of 0.20-240 μmol/L,a sensitivity of 9.995 μA/((μmol/L)?cm2)and a limit of detection(LOD)of 0.06 μmol/L.The sensor exhibited excellent anti-interference capability,good reproducibility,and stability,with spiked recoveries for NFZ in water samples ranging from 94.6%to 105.6%.This study provided a novel electrochemical sensing approach for NFZ detection.

Result Analysis
Print
Save
E-mail