1.Research Progress of Traditional Chinese Medicine in Improving Diabetic Retinopathy Based on Nrf2 Signaling Pathway
Xueqing LIU ; Xinyu ZHONG ; Tingting WANG ; Ning WANG ; Man LIU ; Li WU ; Lili WU ; Lingling QIN ; Tonghua LIU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(9):69-78
Diabetic retinopathy (DR) is a microvascular complication of diabetes and one of its most common complications. Prolonged hyperglycemia induces oxidative stress, inflammatory responses, apoptosis, and pathological angiogenesis, ultimately disrupting the blood-retinal barrier(BRB) and leading to visual impairment or even blindness. Recent studies show that the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway plays an important role in the development of DR's pathological changes. Meanwhile, Chinese herbal monomers have been shown to modulate the Nrf2 signaling pathway, thereby intervening in the development of DR. In terms of inhibiting oxidative stress, saponin compounds such as platycodin-D and ginsenoside Rb1 downregulate the expression of malondialdehyde (MDA), thereby ameliorating retinal oxidative stress. Flavonoids such as total flavonoids from Pueraria lobata flower and puerarin upregulate the expression of superoxide dismutase (SOD) and glutathione peroxidase (GPx), effectively clearing lipid peroxides. Regarding the suppression of inflammation, phenolic compounds like resveratrol and chlorogenic acid inhibit the nuclear factor kappa B (NF-κB) pathway, reducing the release of tumor necrosis factor-alpha (TNF-α) and mitigating inflammatory responses. In the context of inhibiting apoptosis, polysaccharides such as Polygonatum sibiricum polysaccharide and Angelica sinensis polysaccharide downregulate the expression of the pro-apoptotic protein Bcl-2-associated X protein (Bax) and suppress the activity of the executioner Caspase-3, thereby reducing the apoptosis rate. As for the inhibition of neovascularization, compounds including bilobalide and physcion significantly decrease the protein expression of vascular endothelial growth factor (VEGF), leading to a reduction in retinal pathological angiogenesis. Furthermore, Chinese herbal compound prescriptions such as Tongluo Zhujing pills, Yiqi Huoxue Yangyin decoction, Qiming granules, and Danlou tablets can also intervene in the onset and progression of DR through the mechanisms described above. In summary, both Chinese herbal monomers and Chinese herbal compound prescriptions can modulate the Nrf2 signaling pathway to inhibit oxidative stress, alleviate inflammation, and participate in maintaining BRB integrity, suppressing retinal neovascularization, and preventing neurodegeneration, thereby delaying the progression of DR. Therefore, this paper reviews and summarizes recent studies at home and abroad on how traditional Chinese medicine (TCM) works to treat DR, and the relationship between the Nrf2 pathway and DR. It aims to provide research ideas for preventing and treating DR.
2.Mechanism of Shenfu Xiongze Prescription in Regulating Autophagy Level to Intervene in Myocardial Remodeling in Rats via AMPK/mTOR Signaling Pathway
Xueqing WANG ; Wei ZHONG ; Liangliang PAN ; Caihong LI ; Man HAN ; Xiaowei YANG ; Yuanwang YU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(2):136-144
ObjectiveTo explore the mechanism by which the Shenfu Xiongze prescription regulates autophagy in rats with myocardial remodeling through the adenosine monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling pathway. MethodsA rat model of myocardial remodeling induced by isoprenaline (ISO) was established. Rats were divided into the blank group,the model group,the low-,medium-, and high-dose groups of Shenfu Xiongze prescription,and the captopril group, 6 rats in each group. Except for the blank group,the rat model of myocardial remodeling was established in the other groups by intraperitoneal injection of 2.5 mg·kg-1 ISO for 3 consecutive weeks. At the same time of modeling, the low-,medium-, and high-dose groups of Shenfu Xiongze prescription were administered the corresponding doses of Shenfu Xiongze prescription solution (8.4,16.8,and 33.6 g·kg-1),and the captopril group was administered captopril solution (25 mg·kg-1). As for the blank group and the model group, the same volume of normal saline was given. The treatment was continued for 3 weeks. Echocardiography was used to observe the cardiac structure and function,and the heart weight index was detected. Masson staining and hematoxylin-eosin (HE) staining were used to observe the pathological morphology changes of myocardial tissue. The levels of interleukin-6 (IL-6) and B-type natriuretic peptide (BNP) in serum were detected by enzyme-linked immunosorbent assay (ELISA). The expression of type Ⅰ collagen (Collagen Ⅰ),type Ⅲ collagen (Collagen Ⅲ),and microtubule-associated protein 1 light chain 3 (LC3) proteins in myocardial tissue was determined by immunohistochemistry. Autophagy was observed by transmission electron microscopy. The mRNA expression of Collagen Ⅰ,Collagen Ⅲ,α-smooth muscle actin (α-SMA),LC3,yeast Atg6 homolog protein (Beclin-1),AMPK,and mTOR in myocardial tissue was detected by quantitative real-time polymerase chain reaction (real-time PCR). The protein expression of Collagen Ⅰ,α-SMA,transforming growth factor-β1 (TGF-β1),LC3,Beclin-1,p62, phosphorylation(p)-AMPK,p-mTOR,AMPK,and mTOR was detected by Western blot. ResultsCompared with the normal group,rats in the model group exhibited significantly decreased values of ejection fraction (EF) and left ventricular fractional shortening (FS) (P<0.01), significantly increased values of left ventricular end-diastolic diameter (LVIDd) and left ventricular end-systolic diameter (LVIDs) (P<0.01). Additionally, the model group also showed increased degrees of inflammatory infiltration and fibrosis of myocardial tissue, significantly elevated levels of serum IL-6 and BNP (P<0.01), significantly increased mRNA and protein levels of Collagen Ⅰ,Collagen Ⅲ,α-SMA,and mTOR (P<0.01),and markedly decreased mRNA and protein levels of LC3,Beclin-1,and AMPK (P<0.05,P<0.01). Compared with the model group, the low-,medium-, and high-dose groups of Shenfu Xiongze prescription presented significantly elevated EF and FS values (P<0.01) and lowered LVIDd and LVIDs (P<0.05). In these groups, the inflammation and fibrosis were alleviated significantly. They also exhibited decreased serum levels of IL-6 and BNP (P<0.01), significantly reduced protein expression of Collagen Ⅰ, α-SMA, TGF-β1, p62, and p-mTOR (P<0.01), significantly decreased mRNA expression of Collagen Ⅰ, Collagen Ⅲ, α-SMA, and mTOR (P<0.01), and significantly increased mRNA and protein levels of LC3, Beclin-1, and AMPK (P<0.05,P<0.01). ConclusionThe Shenfu Xiongze prescription can improve the myocardial remodeling induced by ISO in rats by regulating the autophagy level,enhance cardiac function,and reduce inflammatory and fibrotic levels. This effect may be achieved through the AMPK/mTOR signaling pathway.
3.Efficacy and safety of sequential or combined therapy with tenofovir alafenamide fumarate in entecavir-treated patients with low-level viremia
Yijing ZHANG ; Lingying HUANG ; Bowu CHEN ; Wanchun ZHU ; Man LI ; Jie SHEN ; Yueqiu GAO
Journal of Clinical Hepatology 2026;42(1):66-73
ObjectiveTo investigate the efficacy of sequential tenofovir alafenamide fumarate (TAF) therapy versus the regimen of entecavir (ETV) combined with TAF in chronic hepatitis B (CHB) patients experiencing low-level viremia (LLV) after ETV therapy, as well as their impact on virologic response, liver and renal function, and blood lipid levels. MethodsA total of 217 CHB patients with LLV after ETV treatment who were admitted to Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine from May 2020 to December 2023 were enrolled, and according to the treatment regimen, they were divided into TAF group (180 patients receiving sequential TAF therapy) and combined group (37 patients receiving ETV+TAF therapy). The propensity score matching (PSM) method was used to match the patients at a ratio of 1∶1, and finally 37 patients were included in each group to balance the baseline confounding factors. The two groups were compared in terms of hepatitis B virus DNA (HBV DNA) clearance rate, hepatitis B envelope antigen (HBeAg) clearance rate, liver and renal function parameters (liver stiffness measurement [LSM], platelet count [PLT], aspartate aminotransferase [AST], alanine aminotransferase [ALT], and creatinine [Cr]), blood lipid levels (total cholesterol [TC], triglyceride [TG], high-density lipoprotein cholesterol [HDL-C], and low-density lipoprotein cholesterol [LDL-C]), and the incidence rate of adverse reactions. The independent samples t-test was used for comparison of normally distributed continuous data between two groups, and the paired t-test was used for comparison within each group; the chi-square test was used for comparison of categorical data between groups. ResultsAfter 48 weeks of treatment, compared with the TAF group, the combined group had significantly higher HBV DNA clearance rate (86.49% vs 59.46%, χ²=6.852, P=0.009) and HBeAg clearance rate (59.46% vs 35.14%, χ²=4.391, P=0.036). After treatment, compared with the TAF group, the combined group had significantly lower levels of LSM (7.01±1.50 kPa vs 7.90±1.68 kPa, t=2.404, P=0.019), AST (18.02±2.28 U/L vs 21.12±2.85 U/L, t=5.166, P<0.001), and ALT (19.85±3.86 U/L vs 22.00±3.90 U/L, t=2.383, P=0.020) and significantly higher levels of PLT [(218.35±42.60)×109/L vs (192.82±44.13)×109/L, t=2.532, P=0.014] and Cr (70.92±6.54 μmoL/L vs 67.60±6.13 μmoL/L, t=2.253, P=0.027). After treatment, there was a slight increase in the level of TC in both the TAF group (5.60±0.89 mmol/L vs 5.18±0.85 mmol/L, t=2.076, P=0.041) and the combined group (5.45±0.80 mmol/L vs 5.02±0.83 mmol/L, t=2.269, P=0.026). There was no significant difference in the incidence rate of adverse reactions between the TAF group and the combined group (21.62% vs 18.92%, χ²=0.084, P=0.772). ConclusionFor ETV-treated CHB patients experiencing LLV, compared with sequential TAF therapy, the ETV+TAF combined therapy can effectively increase virologic response rate, alleviate liver fibrosis, and improve liver function, whereas sequential TAF therapy has less impact on renal function. Sequential or combined therapy with TAF may induce a slight increase in the level of TC, which should be taken seriously in clinical practice.
4.Mechanistic study of mitochondrial dysfunction in renal injury induced by maternal bone lead mobilization during pregnancy in rats
Ling LI ; Lin ZHANG ; Li LI ; Yuting WEI ; Man LYU ; Zeshi ZHANG ; Li MA ; Anxin LU ; Yin LIN ; Shaohua WANG ; Chonghuai YAN
Journal of Environmental and Occupational Medicine 2026;43(3):286-292
Background Lead is a typical persistent environmental pollutant that can accumulate in bones for decades. During pregnancy, alterations in calcium metabolism promote the mobilization of bone lead, resulting in secondary exposure; however, the mechanisms by which pregnancy-associated bone lead mobilization affects maternal renal function remain unclear. Objective To investigate the role of mitochondrial dysfunction in pregnancy-related bone lead mobilization-induced renal injury. Methods Newly weaned female Wistar rats were randomly assigned to a control or a lead-exposed group administered either 0.05% sodium acetate or 0.05% lead acetate in drinking water. Following a 4-week lead exposure and a 4-week washout period, the females were co-housed with healthy age-matched males for mating. Rats were sacrificed at early (gestational day 3) and late (gestational day 17) pregnancystages, respectively. Renal histopathology was assessed using hematoxylin and eosin staining staining. Mitochondria-related indicators, including oxidative stress, inflammatory responses, and energy metabolism, were measured. Differential metabolites were identified using serum metabolomics. Results Renal injury in the lead-exposed pregnant rats progressed in a time-dependent manner, characterized by degeneration of proximal tubular epithelial cells, glomerular hyaline changes, and interstitial inflammatory cell infiltration. Repeated measures ANOVA indicated a significant interaction between the treatment factor (lead exposure) and the temporal factor (gestational stage) on renal injury (P<0.001). Further analysis of mitochondrial function-related indicators in late-pregnancy renal tissue revealed that the lead exposure group exhibited significantly increased levels of malondialdehyde (MDA) and reactive oxygen species (ROS) (P<0.05), accompanied by a reduction in superoxide dismutase (SOD) and reduced glutathione (GSH) activities (P<0.05); regarding inflammatory markers, levels of interleukin-18 (IL-18) and interleukin-1β (IL-1β) were elevated (P<0.01), whereas interleukin-33 (IL-33) was decreased in the lead-exposed group (P<0.05); energy metabolism-related indicators, including adenosine triphosphate (ATP) level, Na+-K+-ATPase and Ca2+-Mg2+-ATPase activities, and mitochondrial respiratory chain complexes I, III, and V activities, were significantly reduced (P<0.05) in the lead-exposed gorup. The typical differential metabolite N-methylisoleucine, identified through serum metabolomics analysis, was negatively correlated with blood lead levels, kidney injury scores, and IL-1β, while positively correlated with catalase (CAT) activity and Ca2+-Mg2+-ATPase. Conclusions Mitochondrial dysfunction may play a critical role in renal injury induced by bone lead mobilization during late gestation.
5.Role of Macrophage Ferroptosis in Immune Evasion of Hepatocellular Carcinoma and Research Progress on Traditional Chinese Medicine Intervention
Jinxiang PENG ; Xiaojuan LI ; Man LU ; Xinhua XU ; Mengxian SHU ; Feng WU
Cancer Research on Prevention and Treatment 2026;53(4):316-324
Hepatocellular carcinoma (HCC) develops within a profoundly immunosuppressive tumor immune microenvironment (TIME), which limits the efficacy of immunotherapy. Polarization of tumor-associated macrophages (TAMs) toward a pro-tumorigenic M2 phenotype is a major driver of immune escape. Ferroptosis, an iron-dependent regulated cell death program, intersects with hepatic iron metabolism and immune regulation and thus offers promising points of therapeutic intervention. This review systematically elucidates the mechanistic role of TAM ferroptosis in HCC immune evasion and highlights a “bidirectional regulation” intervention strategy grounded in the Traditional Chinese medicine (TCM) principle of “fortifying healthy qi and eliminating pathogens” (Fuzheng Quxie). This strategy employs “eliminating pathogens” (Quxie) approaches to exploit the metabolic vulnerability of M2-like TAMs and precisely induce their ferroptosis. Moreover, it utilizes “fortifying healthy qi” (Fuzheng) approaches to protect M1-like TAMs and CD8+ T cells from oxidative damage. This parallel “induction-protection” paradigm demonstrates the unique advantages of TCM in systemically remodeling TIME through multitarget synergistic actions. Accordingly, precision regulation of TAM ferroptosis based on the Fuzheng Quxie theory represents a promising integrative Chinese-Western medicine strategy for overcoming current bottlenecks in HCC immunotherapy, although its clinical translational potential warrants further validation.
6.Study on the safety and efficacy of micro-perfusion device for preserving isolated porcine limbs
Pengkai LI ; Zhaodi MI ; Shen LI ; Man YUAN ; Xiwei PENG ; Jia LÜ ; Sice WANG ; Zhibo JIA ; Xiangyu SONG ; Yixuan ZHU ; Chonghui LI ; Moling XIAO ; Wenjing XU ; Jiang PENG
Organ Transplantation 2026;17(3):422-431
Objective To evaluate the safety and efficacy of a self-developed micro-normothermic machine perfusion (NMP) system (micro-perfusion device) for preserving isolated porcine limbs. Methods Five healthy Landrace pigs were selected, and their left and right forelimbs were randomly divided into the NMP group and static cold storage (SCS) group. The NMP group was perfused with the self-developed micro-perfusion device and polymerized hemoglobin perfusate for 32 hours at normothermia, while the SCS group was preserved at 4 ℃. Hemodynamic parameters such as perfusion pressure and flow were monitored. The pH value, partial pressure of oxygen (PO2), lactic acid (Lac), creatine kinase (CK) and lactate dehydrogenase (LDH) in the perfusate were measured. Hematoxylin-eosin staining was used to assess the muscle tissue structure, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling was employed to evaluate muscle cell apoptosis, and immunohistochemistry staining was applied to detect the expressions of tumor necrosis factor (TNF)-α and interleukin (IL)-6. A mixed-effects model was used to analyze the effects of time and treatment methods on tissue structure, cell apoptosis and inflammatory factors. Results The device could stably maintain a perfusion pressure of (69±15) mmHg and a flow rate of (117±42) mL/min. The pH value and electrolytes of the perfusate were generally stable, with PO2 maintained at a high level. Lac was maintained at 5.38(3.81, 6.45) mmol/L, while CK and LDH increased over time. After 32 hours of perfusion in the NMP group, both the myocyte spacing and apoptosis rate were better than those in the SCS group. Mixed-effects model analysis showed that there were statistically significant differences in the effects of NMP treatment and SCS treatment on myocyte spacing and apoptosis rate per unit time (both P < 0.05). There were no statistically significant differences in TNF-α and IL-6 between the two groups, and mixed-effects model analysis showed no statistically significant differences in the effects of NMP treatment and SCS treatment on TNF-α and IL-6 per unit time (both P > 0.05). Conclusions The micro-perfusion device used in this study may achieve 32-hour normothermic preservation in a porcine limb amputation model, maintain basic metabolism and ionic homeostasis, reduce muscle structural damage and cell apoptosis without inducing additional inflammatory responses. This technology is expected to significantly extend the time window for replantation of amputated limbs in disaster rescue and long-distance transportation, providing an important technical basis for clinical translation and subsequent replantation research.
7.Association of generative artificial intelligence dependence and academic burnout among college students
Chinese Journal of School Health 2026;47(5):652-655
Objective:
To understand the current status of generative artificial intelligence (GenAI) dependence among college students, explore its relationship with basic psychological needs satisfaction, artificial intelligence (AI) literacy, and academic burnout, so as to provide an empirical basis for universities to formulate scientific AI education governance strategies.
Methods:
A stratified cluster sampling method was used to select 1 086 undergraduates from 5 universities in Shenyang from March to May 2025. Surveys were conducted using the GenAI Dependence Scale, Basic Psychological Needs Satisfaction Scale, Academic Burnout Scale, and AI Literacy Scale. Pearson correlation analysis was utilized to examine the correlations among variables, and the PROCESS Model was employed to test the mediating effects.
Results:
The scores for college students GenAI dependence and academic burnout were (2.94±0.86) and (3.15±0.84), respectively. Pearson correlation analysis indicated that GenAI dependence was positively correlated with academic burnout ( r =0.40) and negatively correlated with both basic psychological need satisfaction and AI literacy ( r =-0.39,-0.22)(all P <0.01). Mediation analysis revealed that basic psychological need satisfaction partially mediated the relationship between GenAI dependence and academic burnout, with an effect size of 0.109 (95% CI =0.075-0.148). AI literacy moderated this mediation pathway, yielding a moderated mediation index of -0.051 (95% CI =-0.089 to -0.021). Under low AI literacy levels, the indirect effect of GenAI dependence on academic burnout through basic psychological needs satisfaction was stronger (effect size=0.159, 95% CI =0.108-0.201), whereas high AI literacy effectively buffered this indirect negative impact (effect size=0.058, 95% CI =0.012-0.095).
Conclusion
GenAI dependence not only directly predicts academic burnout but also exerts an indirect effect by thwarting psychological needs satisfaction, with AI literacy playing a moderating role.
8.Variability of remnant cholesterol inflammation index exhibits a dose-response relationship with stroke risk:Evidence from the Chinese Kailuan cohort
Liuliu CAO ; Man LI ; Zhaohui WU ; Maolin ZHAO ; Baohua WANG ; Li ZHANG ; Peng LI ; Yongna YANG ; Weiguo ZHENG ; Haiyan ZHAO ; Shuohua CHEN ; Shouling WU ; Lixia SUN
Journal of Army Medical University 2025;47(22):2847-2857
Objective To investigate the association between the variability of remnant cholesterol inflammatory index(RCII),a novel composite biomarker,and the risk of stroke,in order to provide a theoretical basis for stroke prevention.Methods A prospective cohort study was conducted on 38 659 Kailuan individuals who took annual physical examinations in 2006,2008,and 2010.These subjects were grouped based on the quartiles of RCII variability,which was represented by standard deviation(SD)and average real variability(ARV),and were followed up every 2 years,with the occurrence of stroke(including ischemic and hemorrhagic strokes),death,or the end of follow-up on December 31,2022 as the endpoints.Kaplan-Meier method was used to calculate the cumulative incidence rate of endpoint events across different groups,and log-rank test was used to compare the difference of cumulative incidence of endpoint events in each group.Multivariate Cox proportional hazards regression model was adopted to analyze the association between RCII variability and risk of stroke.Results Among the 38 659 participants,a total of 2 539 strokes occurred during a mean follow-up period of 11.22±2.26 years.After adjusting confounding factors,when the participants were grouped by the quartiles of RCII-SD,the hazard ratio(HR)for stroke was 1.034(95%CI:0.917~1.167,P=0.584),1.146(95%CI:1.018~1.290,P=0.025),and 1.209(95%CI:1.066~1.370,P=0.003),respectively in the Q2,Q3,and Q4 groups,when compared with the Q1 group(Ptrend<0.05).When they were grouped by the quartiles of RCII-ARV,the HR for stroke was 1.008(95%CI:0.894~1.136,P=0.901),1.109(95%CI:0.986~1.248,P=0.085),and 1.152(95%CI:1.018~1.303,P=0.025),respectively,in the Q2,Q3,and Q4 groups,when compared with the Q1 group.Furthermore,both sensitivity and stratified analyses yielded similar results.Conclusion RCII variability is significantly associated with stroke,and the risk of stroke is gradually increasing with increment of the variability.Countermeasures Relevant authorities can focus on reducing RCII variability as a central objective by establishing regular monitoring mechanism,strengthening lifestyle interventions,and standardizing dietary,exercise,and weight management in order to suppress the index fluctuations.The principle of stable lipid-lowering in medication and optimization of therapeutic regimens with stable efficacy should be emphasized to prevent the risk of additional vascular damage.
9.Ion Filtering and Reactivity Investigation Based on Tandem Ion Mobility Spectrometry
Yi-Qian XU ; Qi-Mu YANG ; Man-Man PAN ; Dan-Dan JIANG ; Chuang CHEN ; Hai-Yang LI
Chinese Journal of Analytical Chemistry 2025;53(5):740-748
In analytical techniques such as ion mobility spectrometry(IMS)and mass spectrometry(MS),the ionization efficiency of target analytes is primarily constrained by the type of ionization source and factors such as the species and number density of the reactant ions.Systematic investigation into the reactivity differences of various reactant ions under varying conditions can not only significantly enhance the detection sensitivity of target compound product ions but also provide a theoretical foundation for establishing efficient detection methods based on ion-molecule reaction mechanisms.In this study,the pressure of a pressure-tunable photoionization tandem ion mobility spectrometry(PI-tandem-IMS)was reduced from ambient pressure(100 kPa)to low pressure(20 kPa)to systematically examine the reactivity differences between two negative reactant ions,CO3-and CO4-,and methyl salicylate(MeSA)under varying pressures.When the pressure decreased,the increased relative signal intensity of CO4-significantly influenced the detection sensitivity of the characteristic product ion[MeSA·O2]-.Based on differences in ion mobility(k0),the delay time for the opening of TPG2 was adjusted to selectively inject CO-3 and CO-4 in the drift region 2.Independent characterization of the reactivity of these reactant ions with MeSA in the reaction region confirmed that CO4-exhibited superior reactivity toward MeSA.The theoretical model revealed an Arrhenius plot for the ion-molecule reaction between CO4-and MeSA,showing a positive correlation between the reaction rate coefficient(k)and temperature,the activation energy Ea was 62.45 kJ/mol.Furthermore,controlling parameters such as pressure or temperature significantly influenced the progression of this ion-molecule reaction,demonstrating the technical advantages of PI-tandem-IMS in mechanistic studies and regulation of ion-molecule reactions.
10.Improvement of Performance of Ion Mobility Spectrometry Using A Low Discrimination Bradbury-Nielsen Gate Controlling Method
Qi-Mu YANG ; Yi-Qian XU ; Man-Man PAN ; Dan-Dan JIANG ; Chuang CHEN ; Hai-Yang LI
Chinese Journal of Analytical Chemistry 2025;53(6):875-884
The resolving power and sensitivity are critical for on-site detection of hazardous chemicals using stand-alone ion mobility spectrometry(IMS).However,improving the sensitivity and resolving power of IMS has long been a prominent research hot spot.In the commonly used IMS based on the Bradbury-Nielsen gate(BNG),the gating voltage difference(GVD)applied between the two sets of grid wires affects the electric field distribution in the ionization region and the drift region.This,in turn,influences the spatial distribution and temporal width of the injected ion swarm,and has an impact on the ion mobility discrimination,sensitivity,and resolving power of the instrument.This study showed that increasing the GVD could induce an ion converging effect,boosting the ion number density in front of the BNG by nearly 300%.To simultaneously utilize temporal compression and ion converging effects,a novel BNG controlling mode was proposed by adding a chopping state to the conventional controlling mode.This chopping state reduced the mobility discrimination effects between ions with mobility differences up to about 0.90 cm2/(V·s)to 1/22 of their original value.When analyzing hazardous chemical mixtures using the novel BNG controlling mode,compared with conventional mode,the signal intensity of low-mobility methyl salicylate ions(MS·O2)-increased by 18-fold while the resolving power maintained around 100,and the detection limit for MS was improved from 3.75 μg/L to 97 ng/L.This novel BNG controlling mode only added a potential wave to the low voltage wires,with no requirement of changing the structure of the drift tube,and was easy to apply to existing commercial instruments.


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