1.Serological characteristics of individuals with hepatitis C virus/hepatitis B virus overlapping infection
Yanfei CUI ; Xia HUANG ; Chao ZHANG ; Yingjie JI ; Song QING ; Yuanjie FU ; Jing ZHANG ; Li LIU ; Yongqian CHENG
Journal of Clinical Hepatology 2026;42(1):74-79
ObjectiveTo investigate the status of overlapping hepatitis B virus (HBV) infection in patients with chronic hepatitis C virus (HCV) infection and the serological characteristics of such patients. MethodsA total of 8 637 patients with HCV infection who were hospitalized from January 1, 2010 to December 31, 2020 and had complete data of HBV serological markers were enrolled, and the composition ratio of patients with overlapping HBV serological markers was analyzed among the patients with HCV infection. The patients were divided into groups based on age and year of birth, and serological characteristics were analyzed, and the distribution of HBV-related serological characteristics were analyzed across different HCV genotypes. ResultsThe patients with HCV/HBV overlapping infection accounted for 5.85%, and the patients with previous HBV infection accounted for 48.10%; the patients with protective immunity against HBV accounted for 14.67%, while the patients with a lack of protective immunity against HBV accounted for 31.39%. The patients were divided into groups based on age: in the 0 — 17 years group, the patients with protective immunity against HBV accounted for 61.41% (304 patients); the 18 — 44 years group was mainly composed of patients with previous HBV infection (698 patients, 37.31%), the 45 — 59 years group was predominantly composed of patients with previous HBV infection (1 945 patients, 50.38%), and the ≥60 years group was also predominantly composed of patients with previous HBV infection (1 486 patients, 61.66%). The patients were divided into groups based on the year of birth: in the pre-1992 group, the patients with previous HBV infection accounted for 51.63% (4 112 patients); in the 1992 — 2005 group, the patients with protective immunity against HBV accounted for 54.72% (168 patients); in the post-2005 group, the patients with protective immunity against HBV accounted for 64.38% (235 patients). In this study, 6 301 patients underwent HCV genotype testing: the patients with genotype 1b accounted for the highest proportion of 51.71% (3 258 patients), followed by those with genotype 2a (1 769 patients, 28.07%), genotype 3b (63 patients, 1.00%), genotype 3a (10 patients, 0.16%), genotype 4 (21 patients, 0.33%), and genotype 6a (5 patients, 0.08%). ConclusionWith the implementation of hepatitis B planned vaccination program in China, there has been a significant reduction in the proportion of patients with previous HBV infection among the patients with HCV/HBV overlapping infection, but there is still a relatively high proportion of patients with a lack of protective immunity against HBV.
2.Consistent Detection of Aquaporin-4 Antibodies:A Comparative Analysis Between Fixed and Live Cell-Based Assays
Jing WANG ; Linge WANG ; Xiaolin YANG ; Zhizhong LI ; Jinyu JIANG ; Qiao XU ; Siyuan HUANG ; Qing FU ; Yang YANG ; Rongrong ZHANG ; Lin YANG ; Ai CHEN ; Xiaopeng ZENG ; Ke XU ; Peng ZHENG ; Xinyue QIN ; Jinzhou FENG
Journal of Clinical Neurology 2026;22(2):212-220
Background:
and Purpose Live cell-based assays (LCBA) are increasingly used for serological antibody detection due to their ability to preserve antigen conformation, offering moderately higher sensitivity than fixed cell-based assays. However, the clinical necessity of prioritizing LCBA for the detection of aquaporin-4 immunoglobulin G (AQP4-IgG) in neuromyelitis optica spectrum disorder (NMOSD) remains unclear, especially when compared to its established role in diagnosing myelin oligodendrocyte glycoprotein antibody-associated disease.
Methods:
We compared the performance of live cell-based assays using immunofluorescence (LCBA-IF) and fixed cell-based assays using immunofluorescence (FCBA-IF) in detecting AQP4-IgG in 90 cases of NMOSD meeting 2015 International Panel for Neuromyelitis Optica Diagnosis criteria, alongside 40 controls. Additionally, we further investigated the relationship between AQP4-IgG titers as measured by LCBA-IF and FCBA-IF and clinical parameters in NMOSD patients.
Results:
Results showed 96.9% agreement between LCBA-IF and FCBA-IF (Cohen’s κ=0.935), with a strong Spearman correlation (0.977, p<0.001). Both methods demonstrated 100% specificity, with LCBA-IF showing slightly higher sensitivity compared to FCBA-IF. Within LCBAIF-tested groups, statistically significant differences in annualized relapse rates were observed across all pairwise comparisons (low-titer vs. moderate-titer, low-titer vs. high-titer, and moderate-titer vs. high-titer; all p<0.050). However, this association reached statistical significance in some FCBA-IF-tested groups.
Conclusions
Overall, there is a strong concordance between LCBA-IF and FCBA-IF in detecting AQP4-IgG, where LCBA-IF shows slightly higher sensitivity. Furthermore, there is a potential link between elevated AQP4-IgG titers and an increased risk of relapse, and this correlation may appear more pronounced when using LCBA-IF.
3.Clinicopathological characteristics and diagnostic strategies of prostatic paraganglioma presenting with prostatic mass and micturition-associated symptoms
Mengjie ZHANG ; Qun LU ; Yao FU ; Qing ZHANG ; Weidong GAN ; Hongqian GUO
Journal of Modern Urology 2026;31(6):552-558
Objective To evaluate the clinical characteristics, diagnostic reasoning, and therapeutic strategies of prostatic paraganglioma (PPG) to provide an evidence-based foundation for early diagnosis and precision treatment of this rare malignancy. Methods The clinical data of a patient with PPG admitted to our hospital were retrospectively analyzed. Concurrently, a systematic search was conducted across domestic and international databases, including PubMed, CNKI, and Wanfang.Clinical manifestations, laboratory tests, pathological features, therapeutic modalities, and prognostic data of 24 cases reported between 1979 and 2025 were pooled with the institutional case for a comprehensive analysis (n=25). Results Epidemiological features: the age at onset ranged from 8 to 76 years, with a mean age of (44.6±15.2) years, predominantly affecting young and middle-aged adults (30-50 years).Notably, 20.0% (5/25) of the patients exhibited characteristic micturition-associated catecholamine release symptoms (e.g., post-micturition palpitations, transient hypertension).Laboratory findings: among the 19 patients who underwent catecholamine metabolite testing, 14 (73.7%) showed significant elevation in serum or urinary norepinephrine and methoxyadrenaline levels.Pathological and immunohistochemical features: the positivity rate for neuroendocrine markers (chromogranin A, synaptophysin, and neuron-specific enolase) was 100%, while the negativity rate for prostate-specific markers (prostate-specific antigen and prostate-specific acid phosphatase) was also 100%.Treatment and prognosis: surgical intervention was performed in 96.0% (24/25) of the patients, including radical prostatectomy (37.5%), precision tumor excision (25.0%), and transurethral resection (12.5%).Favorable outcomes without recurrence were observed in 89.5% (17/19) of the total cohort. Conclusion PPG is clinically exceedingly rare.The disease should be highly suspected in patients presenting with a prostatic mass, normal prostate-specific antigen level, and micturition-associated cardiovascular symptoms.Testing for catecholamine metabolites is the key screening tool.Robot-assisted surgery facilitates precise tumor excision while ensuring optimal functional preservation.Given the malignant potential and genetic correlations of PPG, lifelong follow-up is recommended.
4.Characteristics of changes in HBsAg,HBV DNA and ALT after cessation of nucleos(t)ide analogue therapy in patients with HBeAg-negative chronic hepatitis B
Qiao-Lan LYU ; Li LIU ; Song QING ; Ying-Jie JI ; Yan LIU ; Chao ZHANG ; Fu-Sheng WANG ; Yong-Qian CHEN
Medical Journal of Chinese People's Liberation Army 2025;50(9):1076-1082
Objective To investigate the characteristics of changes in hepatitis B surface antigen(HBsAg),hepatitis B virus(HBV)deoxyribonucleic acid(DNA),and alanine aminotransferase(ALT)levels following the cessation of nucleos(t)ide analogues(NAs)therapy in hepatitis B e antigen(HBeAg)-negative chronic hepatitis B(CHB)patients with baseline HBsAg levels<1000 IU/ml.Methods This retrospective cohort study analyzed 73 HBeAg-negative CHB patients treated at the Fifth Medical Centre of Chinese PLA General Hospital from January 2020 to June 2023.Patients were divided into 3 groups according to baseline HBsAg level and discontinuation strategy:HBsAg-negative discontinuation group(n=14),HBsAg-positive discontinuation group(n=25),and HBsAg-positive continuation group(n=34).All patients were followed for 48 weeks.Baseline clinical characteristics and changes in virological and hepatic biochemical indicators during follow-up were compared among the 3 groups.Univariate logistic regression analysis was performed to assess the correlation between clinical indicators and HBV DNA reappearance in HBsAg-positive discontinuation group,and between clinical indicators and HBsAg decline>0.5 log IU/ml in this group.Results There were no significant differences in the baseline levels of gender,age,albumin,and total bilirubin among the 3 groups(P>0.05).The baseline direct bilirubin level was significantly higher in HBsAg-positive discontinuation group than that in other groups(P<0.05),while the lymphocyte counts were significantly higher in HBsAg-negative discontinuation group(P<0.05).During the 48-week follow-up period,the HBV DNA reappearance rate in HBsAg-positive discontinuation group(72.0%)was significantly higher than that in other groups(P<0.001).There was no significant difference in the incidence of ALT elevation among the three groups(P=0.260).The proportion of patients with HBsAg decline>0.5 log IU/ml in HBsAg-positive discontinuation group(24.0%)was significantly higher than that in HBsAg-positive continuation group(5.9%,P<0.05).The proportion of patients with HBsAg increase>0.5 log IU/ml in HBsAg-positive discontinuation group(12.0%)was also significantly higher than that in HBsAg-positive continuation group(0%,P<0.05).Univariate logistic regression analysis revealed no significant association between the analyzed clinical indicators and HBsAg decline(P>0.05).Conclusions Discontinuation of NAs therapy in HBsAg-negative patients demonstrates high safety,with sustained HBsAg negativity post-cessation and low risks of viral relapse and liver function abnormalities.For HBsAg-positive patients,discontinuation may promote HBsAg decline in some individuals but is associated with risks of HBV DNA reappearance and HBsAg elevation.The decision to discontinue therapy should be comprehensively evaluated based on patients'baseline HBsAg levels and clinical characteristics.
5.Quality evaluation of Xinjiang Rehmannia glutinosa and Rehmannia glutinosa based on fingerprint and multi-component quantification combined with chemical pattern recognition.
Pan-Ying REN ; Wei ZHANG ; Xue LIU ; Juan ZHANG ; Cheng-Fu SU ; Hai-Yan GONG ; Chun-Jing YANG ; Jing-Wei LEI ; Su-Qing ZHI ; Cai-Xia XIE
China Journal of Chinese Materia Medica 2025;50(16):4630-4640
The differences in chemical quality characteristics between Xinjiang Rehmannia glutinosa and R. glutinosa were analyzed to provide a theoretical basis for the introduction and quality control of R. glutinosa. In this study, the high performance liquid chromatography(HPLC) fingerprints of 6 batches of Xinjiang R. glutinosa and 10 batches of R. glutinosa samples were established. The content of iridoid glycosides, phenylethanoid glycosides, monosaccharides, oligosaccharides, and polysaccharides in Xinjiang R. glutinosa and R. glutinosa was determined by high performance liquid chromatography-diode array detection(HPLC-DAD), high performance liquid chromatography-evaporative light scattering detection(HPLC-ELSD), and ultraviolet-visible spectroscopy(UV-Vis). The determination results were analyzed with by chemical pattern recognition and entropy weight TOPSIS method. The results showed that there were 19 common peaks in the HPLC fingerprints of the 16 batches of R. glutinosa, and catalpol, aucubin, rehmannioside D, rehmannioside A, hydroxytyrosol, leonuride, salidroside, cistanoside A, and verbascoside were identified. Hierarchical cluster analysis(HCA) and principal component analysis(PCA) showed that Qinyang R. glutinosa, Mengzhou R. glutinosa, and Xinjiang R. glutinosa were grouped into three different categories, and eight common components causing the chemical quality difference between Xinjiang R. glutinosa and R. glutinosa in Mengzhou and Qinyang of Henan province were screened out by orthogonal partial least squares discriminant analysis(OPLS-DA). The results of content determination showed that there were glucose, sucrose, raffinose, stachyose, polysaccharides, and nine glycosides in Xinjiang R. glutinosa and R. glutinosa samples, and the content of catalpol, rehmannioside A, leonuride, cistanoside A, verbascoside, sucrose, and glucose was significantly different between Xinjiang R. glutinosa and R. glutinosa. The analysis with entropy weight TOPSIS method showed that the comprehensive quality of R. glutinosa in Mengzhou and Qinyang of Henan province was better than that of Xinjiang R. glutinosa. In conclusion, the types of main chemical components of R. glutinosa and Xinjiang R. glutinosa were the same, but their content was different. The chemical quality of R. glutinosa was better than Xinjiang R. glutinosa, and other components in R. glutinosa from two producing areas and their effects need further study.
Rehmannia/classification*
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Drugs, Chinese Herbal/chemistry*
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Chromatography, High Pressure Liquid/methods*
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Quality Control
6.Early impact of robot-assisted total knee arthroplasty on the treatment of varus knee arthritis.
Xin YANG ; Qing-Hao CHENG ; Fu-Qiang ZHANG ; Hua FAN ; Fu-Kang ZHANG ; Zhuang-Zhuang ZHANG ; Yong-Ze YANG ; An-Ren ZHANG ; Hong-Zhang GUO
China Journal of Orthopaedics and Traumatology 2025;38(4):343-351
OBJECTIVE:
To investigate the clinical efficacy and advantages of robot-assisted total knee arthroplasty (TKA) in patients with varus knee osteoarthritis.
METHODS:
Between October 2022 and June 2023, a total of 59 patients with severe knee osteoarthritis resulting in varus were treated with total knee arthroplasty, aged from 59 to 81 years with an average (70.90±4.63) years, including 19 mals and 40 females. The patients were divided into two groups based on the surgical method used:28 patients in the robot group and 31 patients in the traditional group. The robot group consisted of 8 males and 20 femalse patients, with an average age of (70.54±4.80) years and an average disease duration of (14.89±8.72) months. The traditional group consisted of 11 males and 20 females patients, with an average age of (71.39±4.5) years and an average disease duration of (12.32±6.73) months. The operative duration, amount of bleeding during the operation, postoperative activity time after the operation, hip-knee-ankle angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), and complications were compared between the two groups before and after the operation. Lateral tibia component (LTC), frontal tibia component (FTC), frontal femoral component (FFC) and lateral femoral component (LFC) were measured 6 months after operation Additionally, the degree of knee joint motility, American Knee Society score (KSS), and visual analogue scale(VAS) were compared before and after the operation.
RESULTS:
All patients had gradeⅠwound healing without any complications, and all patients were followed up for 6 to 8 months, with an average of (6.5±1.5) months. There were no significant differences preoperative imaging evaluation indexes (including HKA, LDFA, and MPTA), preoperative knee mobility, preoperative VAS, and preoperative KSS between the two groups (P>0.05). Comparing the operation time (109.11±7.16) min vs. (83.90±7.85) min, length of the incision (16.60±2.33) cm vs. (14.47±1.41) cm, intraoperative bleeding (106.93±6.15) ml vs. (147.97±7.62) ml, postoperative activity time (17.86±1.84) h vs. (21.77±2.68) h, between the two groups showed statistically significant differences (P<0.05). There were significant differences in FFC (88.96±0.84)° vs. (87.93±1.09)° and LFC (88.57±1.10)° vs. (87.16±1.2)° between the two groups at 6 months after operation (P<0.05). The robotic group 1, 3, 6 months after KSS (75.96±3.96), (81.53±3.78), (84.50±3.29) scores, VAS (3.68±0.67), (2.43±0.79), (0.54±0.64), knee joint mobility (113.32±4.72) °, (123.93±3.99) °, (135.36±2.34) °;Traditional group KSS (73.77±4.18), (76.48±3.60), (80.19±3.28) scores, VAS (4.16±1.04), (3.03±0.75), (1.42±0.76) scores, knee joint mobility (109.19±6.95) °, (119.94±6.08) °, (134.48±2.14) °. Compared to before surgery, both groups showed significant improvement in KSS, VAS and knee mobility during the three follow-up visits (P<0.001). Additionally, postoperative HKA (180.39±1.95)° vs. (178.52±2.23)°, LDFA (89.67±0.63) ° vs. (89.63±0.63)°, and MPTA (89.44±0.55)° vs. (89.29±0.60)° were significantly improved in both groups compared to before surgery (P<0.001). The robotic group had higher KSS than the traditional group at 1, 3, and 6 months after surgery (P<0.05). The robotic group also had lower VAS than the traditional group at 1, 3, and 6 months after surgery (P<0.05). Furthermore, knee mobility was higher in the robotic group than those in the traditional group at 1 and 6 months after surgery (P<0.05), but there was no significant difference between the two groups at 6 months after surgery.
CONCLUSION
Robot-assisted total knee arthroplasty is a safe and effective method for total knee replacement. The use of robotics can improve the limb axis and prosthesis alignment for patients with preoperative varus deformity, resulting in better clinical and imaging outcomes compared to the conventional group.
Humans
;
Female
;
Male
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Arthroplasty, Replacement, Knee/methods*
;
Aged
;
Middle Aged
;
Osteoarthritis, Knee/physiopathology*
;
Aged, 80 and over
;
Robotic Surgical Procedures/methods*
7.Mechanism of action of immune molecules and related immune cells in liver failure
Qi LUO ; Biyu ZENG ; Rong ZHANG ; Guojuan MA ; Lei QING ; Liangjiang HUANG ; Lei FU ; Chun YAO
Journal of Clinical Hepatology 2025;41(6):1213-1219
Liver failure (LF) is a severe clinical syndrome characterized by severe impairment or decompensation of liver function. At present, the key role of immune molecules in the pathogenesis of LF has been well established. These molecules not only directly participate in the pathological process of LF, but also influence the course of LF by modulating the behavior of immune cells. In addition, immune molecules can be used as potential biomarkers for evaluating the prognosis of LF. This article summarizes the role of immune molecules in LF and explores the therapeutic strategies based on these immune molecules, in order to provide new directions for the diagnosis and treatment of LF.
8.Arthroscopic suture anchor fixation for acute bony Bankart lesions: excellent bone healing with a low complication rate
Qiangqiang LI ; Peng SUN ; Yu ZHANG ; Kai FU ; Yao YAO ; Jianghui QIN ; Jin XIONG ; Qing JIANG ; Dongyang CHEN
Chinese Journal of Orthopaedics 2025;45(8):523-530
Objective:To investigate the clinical outcomes of arthroscopic suture anchor fixation for acute bony Bankart lesions.Methods:Data of 49 patients with acute bone Bankart injury treated with suture anchor fixation under arthroscopy at the Affiliate Nanjing Drum Tower Hospital of Nanjing University School of Medicine from February 2019 to July 2024 were retrospectively analyzed, including 34 males and 15 females, aged 46.4±17.7 years (range, 18-81 years). Body mass index was 26.3±4.2 kg/m 2 (range, 19.8-37.9 kg/m 2). There were 17 patients with left shoulder and 32 patients with right shoulder. The time from injury to operation was 12.6±10.5 d (range, 1-50 d). CT three-dimensional reconstruction showed that the area of bone defect accounted for 20.1%±11.4% (range, 8%-49%) of the glenoid area. According to the degree of bone defect, there were 38 cases in the bone defect area ≤25% group and 11 cases in the bone defect area >25% group. All 49 patients received shoulder arthroscopic fixation with wire anchor. All 49 the patients were treated under shoulder arthroscopy using suture anchor technique. Using American Shoulder & Elbow Surgeon (ASES) score, University of California, Los Angeles (UCLA) score, Rowe score as well as shoulder range of motion to evaluate shoulder function. The position and healing of the fracture mass were evaluated with shoulder joint CT and three-dimensional reconstruction at immediate and final follow-up. Results:The incision healed in one stage and no infection occurred in all patients. All 49 patients were followed up for a period of 3 to 81 months, with an average follow-up of 23.8±20.2 months. At the final follow-up, the mean forward elevation, external rotation, and internal rotation improved from 126.1°±20.3°, 36.9°±14.0°, and 10±2 preoperatively to 167.1°±15.5°, 66.8°±8.3°, and 6±1 at the last follow-up, respectively ( P<0.05). At the final follow-up, the mean ASES score, UCLA score, and Rowe score were all significantly improved from 41.3±11.9, 14.2±6.1 and 46.9±14.7 preoperatively to 89.7±7.8, 31.5±3.6 and 92.4±7.4, respectively ( P<0.05). The differences between the final follow-up and preoperative values for forward elevation in the bone defect area >25% group and the bone defect area ≤25% group were 43°±20° and 41°±21°, respectively. The differences in lateral external rotation were 34°±8° and 29°±18°, while the differences in internal rotation (measured by hand-behind-back reach) were 5±2 and 4±2, respectively. None of these differences were statistically significant. The differences between the final follow-up and preoperative scores in the bone defect area >25% fracture fragment group and the bone defect area ≤25% group were as follows: ASES score, 50.9±14.4 vs. 47.7±12.8; UCLA score, 18.4±3.2 vs. 17.0±6.9; and Rowe score, 40.5±13.5 vs. 46.9±15.0. None of these differences were statistically significant. CT examination at the last follow-up showed that all fractures were healed, all patients in the bone defect area ≤25% group achieved good reduction, and 3 patients in the bone defect area >25% group had step-offs on the glenoid surface. Postoperative shoulder adhesion occurred in 5 patients, which was improved after intensive abduction and external rotation exercise. Conclusions:Arthroscopic suture anchor fixation is effective for the bone defect area ≤25% bony Bankart lesions, offering advantages of minimal invasiveness and rapid recovery. For lesions involving more than the bone defect area 25% of the glenoid surface, enhanced fixation strength is recommended to prevent fracture fragment displacement.
9.Predictive value of high-sensitivity cardiac troponin T for death in old patients with stable coronary heart disease
Shaojing ZHANG ; Qing WANG ; Linlin FU ; Yunjing CUI ; Xueliang ZHAI
Chinese Journal of Geriatric Heart Brain and Vessel Diseases 2025;27(7):881-884
Objective To investigate the value of hs-cTnT in predicting all-cause death in the elderly with SCAD.Methods A prospective cohort observation study was conducted on 274 old adults with SCAD hospitalized in our department from January 2016 to January 2019.Their hs-cTnT level was measured,and according to the results,they were divided into lower(≤13.0 ng/L,94 cases),middle(14.0-22.0 ng/L,94 cases)and upper(≥23.0 ng/L,86 cases)tertile groups.The general clinical data were compared among the three groups.Kaplan-Meier survival curve was drawn to analyze the survival differences among groups.Cox proportional hazards regression analysis was applied to identify risk factors for mortality.ROC curve analysis was applied to evaluate the predictive value of hs-cTnT for all-cause mortality.Results During a me-dian follow-up period of 32 months,62(22.63%)patients died among the 274 patients,account-ing for 75.8%dying of non-cardiovascular diseases.There were statistically differences in the three tertile groups in terms of age,male ratio,proportions of hypertension,chronic obstructive pulmonary disease and chronic kidney disease,number of comorbidities,estimated glomerular fil-tration rate,albumin and hemoglobin levels,left ventricular ejection fraction,left ventricular mass index,and mortality rate(P<0.05,P<0.01).COX proportional hazards regression model showed the upper tertile group had significantly lower cumulative survival rate than the middle and lower tertile groups(Plog rank<0.01).Multivariate Cox proportional hazards regression analysis indicated that hs-cTnT≥23.0 ng/L level was still a risk factor for death in both model 2(HR=3.749,95%CI:1.703-8.256,P=0.001)and model 3(HR=2.990,95%CI:1.358-6.581,P=0.007).ROC curve analysis revealed that the AUC value of hs-cTnT level in predicting death was 0.736,with a cut-off value of 25 ng/L.Conclusion For elderly SCAD patients,despite the existence of multiple comorbidities and the priority of non-cardiovascular death,hs-cTnT,a marker reflecting myocar-dial injury,is still a predictor for risk of death in the population.
10.Ion Unidirectional Ejection Simulation Study of An Extremely Miniature Hyperbolic Linear Ion Trap
Yun-Fan HE ; Zhuo-Qing YANG ; Yan WANG ; Jiu-Wen SUN ; Yun-Na SUN ; Lu-Yue ZHU ; Di ZHANG ; Feng-Dan WANG ; Min LIU ; Gui-Fu DING ; Jin-Yuan YAO
Chinese Journal of Analytical Chemistry 2025;53(6):885-893
With the increasing demand for dynamic,real-time and rapid qualitative analysis of chemical composition in areas such as emergency response and space exploration,chip-scale mass spectrometers have attracted significant attention.These devices are expected to drive the integration of mass spectrometry with micro/nano-fabrication and intelligent sensing technologies,fostering profound innovation and breakthroughs in analytical chemistry.As an excellent mass analyzer,the ion trap exhibits numerous advantages,and its miniaturization creates favorable conditions for the high-density integration of miniature mass spectrometers.However,the reduction in ion storage capacity may compromise its sensitivity and dynamic range,rendering the study of ion unidirectional ejection in highly miniaturized ion traps of significant practical importance.In this work,a research was conducted on achieving efficient ion unidirectional ejection while maintaining high mass resolution in the extremely miniature hyperbolic linear ion trap(M-HLIT)with a field radius of 1 mm,and an electric field compensation method was proposed,which combined asymmetric electrode stretching and unbalanced RF voltage to achieve high-precision optimization of the electric field composition.Simulations showed that in an ideal structure,this method achieved 100%unidirectional ejection efficiency with the mass resolution of 518,significantly outperforming traditional asymmetric structure method(365)and unbalanced voltage method(321).Following the introduction of ion ejection slots,further optimization through bidirectional stretching and electrical parameters improved the resolution to 790 while maintaining a unidirectional ejection efficiency of 93%.This method eliminated the requirement for additional excitation voltage,offering an ideal solution for the miniature mass analyzer with high detection performance of chip-level mass spectrometers.

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