1.Pre-operative risk assessment of hepatocellular carcinoma recurrence in liver transplant recipients by non-invasive detection of pre-existing genetic lesions
Suqin YANG ; Sunbin LING ; Jianhua LI ; Yan WANG ; Jiapei WANG ; Qiwei HUANG ; Fanming LIU ; Yiqi ZHUANG ; Yingyu ZHENG ; Rui WANG ; Zhe YANG ; Xiaoping ZHENG ; Kai WANG ; Zhikun LIU ; Jun CHEN ; Jianguo WANG ; Haiyang XIE ; Lin ZHOU ; Leiming CHEN ; Guoqiang CAO ; Dandan CHEN ; Junfang JI ; Bin ZHAO ; Chao JIANG ; Di LU ; Xuyong WEI ; Hangjin JIANG ; Qiaonan SHAN ; Hengbo SHI ; Yong-Zhen XU ; Shusen ZHENG ; Zhengxin WANG ; Shengda LIN ; Xiao XU
Clinical and Molecular Hepatology 2026;32(2):884-903
Background/Aims:
Liver transplantation (LT) following total hepatectomy is a life-saving treatment for hepatocellular carcinoma (HCC). The HCC recurrence after LT hinders the effectiveness of the procedure. The objective of this study is to develop a pre-operative risk stratification model based on a liquid biopsy.
Methods:
We conducted a comprehensive multi-omics study of 260 HCC patients from three centers, including clinical data, low-coverage whole-genome sequencing of cell-free DNA (cfDNA) from plasma, as well as whole-exome, single-nucleus RNA, and spatial transcriptomics from matched tumor and non-tumor tissues.
Results:
We identified cfDNA-derived copy number alteration (CNA) signatures associated with post-transplant recurrence. By integrating cfDNA-derived CNA profiles with single-cell transcriptomic data, we traced recurrence-associated cfDNA to a distinct subpopulation of malignant cells within the primary tumor. These cells were embedded in a pro-metastatic microenvironment of specialized endothelial subtypes and cancer-associated fibroblasts. Notably, most recurrence-associated lesions were detectable in cfDNA prior to liver transplantation (LT). Building on these insights, we developed the ZJU Criteria based on CNA fragments and tumor markers, a pre-LT risk prediction tool that integrates conventional clinical factors with cfDNA-derived CNA signatures, and validated it using internal and independent external cohorts.
Conclusion
Our findings suggest that post-transplant recurrence commonly originates from advanced subclones that emerge late during tumor evolution. The ZJU Criteria provides an accurate, non-invasive strategy that significantly improves pre-LT risk stratification and clinical decision-making for patients with HCC.
2.Study on The Anti-aging Effects of Longevity-enriched Metabolite Dimethylglycine
Jie HU ; Gong-Yu PU ; Jun-Lin LI ; Ju CAO ; Zhi-Xin LIN ; Wei-Wei AN ; Xue-Meng LI ; Jing AN
Progress in Biochemistry and Biophysics 2026;53(4):1048-1061
ObjectiveThe exacerbating trend of global population aging poses profound socioeconomic and public health challenges, making the comprehensive elucidation of biological aging mechanisms and the discovery of effective anti-aging interventions an urgent priority in the life sciences. Based on our previous serum metabolomics findings that dimethylglycine, an intermediate metabolite of amino acid metabolism naturally present in the human body, was significantly enriched in the serum of longevity families, this study aimed to systematically investigate the anti-aging effects of dimethylglycine both in living organisms and in controlled laboratory environments, and to preliminarily elucidate its underlying molecular mechanisms. While existing literature indicates that dimethylglycine possesses antioxidant and immunomodulatory properties, its direct anti-aging efficacy and the specific molecular pathways through which it operates remain largely unexplored. MethodsTo comprehensively evaluate the anti-aging properties of dimethylglycine, we utilized replicative senescent human embryonic lung fibroblasts, specifically the WI-38 cell line, as an experimental model in a controlled laboratory environment. Cell viability and safety were thoroughly assessed using Cell Counting Kit-8 and lactate dehydrogenase release assays across various concentrations of dimethylglycine. The impact of dimethylglycine on cellular senescence phenotypes, oxidative stress, and proliferative capacity was evaluated via senescence-associated beta-galactosidase staining, reactive oxygen species fluorescence detection, and 5-ethynyl-2'-deoxyuridine incorporation assays. Furthermore, the molecular alterations of senescence-associated secretory phenotype factors and core senescence signaling pathways were quantified using quantitative reverse transcription polymerase chain reaction for the messenger RNA levels of interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1, and enzyme-linked immunosorbent assay for the measurement of p16 and p21 protein expression levels. For the living organism model, the wild-type nematode Caenorhabditis elegans was used to evaluate systemic physiological effects. We conducted a comprehensive lifespan analysis at 20°C, heat stress resistance survival assays at 35℃, senescence-associated beta-galactosidase staining, lipofuscin accumulation tracking, intracellular reactive oxygen species measurement, and Oil Red O staining to ascertain systemic lipid accumulation. Additionally, network pharmacology bioinformatics tools, including PharmMapper and STRING databases, and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were utilized to predict target pathways, alongside highly detailed molecular docking simulations utilizing SwissDock and Protein-Ligand Interaction Profiler to examine interactions with the cytochrome P450 family 2 subfamily C member 9 protein. ResultsThe experimental outcomes robustly demonstrate the potent anti-aging capabilities of dimethylglycine. At the cellular level, toxicity analyses firmly confirmed that dimethylglycine is highly safe; continuous treatment with 50 mol/L and 70 mol/L of dimethylglycine for 5 d did not induce any cellular membrane damage or cytotoxicity, but rather actively promoted cellular proliferation. Utilizing the optimal standardized concentration of 50 mol/L, dimethylglycine treatment significantly ameliorated senescent phenotypic markers in human embryonic lung fibroblasts, which was evidenced by a drastic and highly significant reduction in the senescence-associated beta-galactosidase positive cell percentage (P<0.000 1) and intracellular reactive oxygen species levels (P<0.000 1), alongside a marked increase in the 5-ethynyl-2'-deoxyuridine-positive proliferation rate (P=0.003 5). On a molecular expression scale, dimethylglycine significantly downregulated the messenger RNA expression of multiple core senescence-associated secretory phenotype inflammatory factors, including interleukin-6, interleukin-8, p21, and matrix metalloproteinase-1. Concurrently, it effectively suppressed the protein expression of critical cell cycle arrest markers, diminishing p16 protein levels by 57.3% (P=0.000 4) and p21 protein levels by 27.2% (P=0.000 7). In the nematode Caenorhabditis elegans animal model, dimethylglycine significantly extended the mean lifespan from 20.402 d to an impressive 23.066 d (P<0.000 1) and notably enhanced overall survival rates under severe heat stress environmental conditions (P=0.017). Furthermore, systemic dimethylglycine intervention significantly mitigated age-related physiological decline by decreasing bodily lipofuscin accumulation (P<0.000 1), significantly reducing senescence-associated beta-galactosidase activity, lowering systemic reactive oxygen species fluorescence (P=0.008), and effectively alleviating overall fat accumulation (P<0.000 1). Mechanistically, extensive network pharmacology and Kyoto Encyclopedia of Genes and Genomes analyses strongly revealed that the potential targets of dimethylglycine are significantly enriched in fundamental drug metabolism and oxidative stress response pathways. Precision molecular docking simulations conclusively demonstrated that dimethylglycine forms highly stable structural interactions with the cytochrome P450 family 2 subfamily C member 9 protein, specifically highlighting the definitive formation of 5 stable hydrogen bonds involving serine 365, leucine 366, and serine 429 residues, as well as two critical salt bridge formations with arginine 97 and histidine 368 residues. It is additionally predicted to interact favorably with glutathione S-transferase family proteins. ConclusionDimethylglycine exhibits a profoundly significant and multifaceted anti-aging activity at both the cellular and entire living animal levels. By powerfully alleviating oxidative stress, heavily suppressing the core p16 and p21-dependent cellular senescence signaling pathways, and substantially mitigating the detrimental senescence-associated secretory phenotype, dimethylglycine effectively delays fundamental cellular senescence processes and drastically extends whole-organism lifespan. The biological mechanisms driving these robust protective effects are highly likely closely associated with its direct stable interactions with crucial metabolic and detoxifying enzyme systems, such as cytochrome P450 family 2 subfamily C member 9 and glutathione S-transferase family proteins, thereby systemically improving metabolic dysregulation and restoring critical redox homeostasis. This comprehensive study provides highly solid experimental evidence supporting dimethylglycine as a highly potent and safe potential anti-aging intervention agent, while simultaneously offering a clear molecular mechanistic explanation for the previously documented high abundance of dimethylglycine observed within exceptionally long-lived human populations.
3.Effect of Runmu Dihuang Decoction on Perimenopausal Dry Eye in Rats with Liver-kidney Yin Deficiency Syndrome Based on SIRT3/HIF-1α/NF-κB Signaling Pathway
Sainan TIAN ; Wei MA ; Yao CHEN ; Yu CAO ; Guicheng LIU ; Pei LIU ; Junxian LEI ; Qinghua PENG ; Jun PENG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(7):201-210
ObjectiveTo investigate the mechanisms of Runmu Dihuang decoction (RMDHD) in treating perimenopausal dry eye with liver-kidney Yin deficiency syndrome based on the silent information regulator 3 (SIRT3)/hypoxia-inducible factor-1α (HIF-1α)/nuclear factor-κB (NF-κB) signaling pathway. MethodsSixty female Sprague-Dawley rats were randomly divided into six groups (n=10 per group): Sham operation group, model group, sodium hyaluronate eye drop group, and low-, medium-, and high-dose RMDHD groups (5.625, 11.25, 22.50 g·kg-1). Except for the sham operation group, all rats underwent bilateral ovariectomy and were administered 0.1% benzalkonium chloride eye drops combined with long-term chronic irritation to establish a perimenopausal dry eye model with liver-kidney Yin deficiency syndrome. Drug administration began in the 11th week after modeling and continued for 21 days. General conditions, screen-grip test scores, tear secretion volume, tear film breakup time (TFBUT), and corneal fluorescein staining were recorded. Serum levels of reactive oxygen species (ROS), follicle-stimulating hormone (FSH), estradiol (E2), and progesterone (PROG) were measured by enzyme-linked immunosorbent assay (ELISA). Pathological changes in the lacrimal glands, corneas, and uteri were observed using hematoxylin-eosin (HE) staining. Protein expression levels of SIRT3, HIF-1α, phosphorylated NF-κB p65 (p-NF-κB p65), and total NF-κB p65 in the lacrimal glands were detected by Western blot. The expression of inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the lacrimal glands was assessed by immunohistochemistry (IHC). ResultsAfter model establishment, no significant differences were observed among the groups except the sham operation group. Compared with the sham operation group, the other groups exhibited slowed movement, dull responses, increased irritability, reduced body weight, elevated rectal temperature, decreased screen-grip test scores, reduced tear secretion, and significantly shortened TFBUT (P<0.05). After treatment, compared with the model group, the sodium hyaluronate eye drop group and all RMDHD groups showed improved general conditions, significantly increased tear secretion (P<0.05), prolonged TFBUT (P<0.05), and elevated screen-grip test scores (P<0.05). Serum ROS and FSH levels were significantly decreased, while E2 and PROG levels were significantly increased (P<0.05). Pathological damage to the cornea, lacrimal glands, and uterus was ameliorated. In addition, protein expression levels of SIRT3 and HIF-1α in the lacrimal glands were significantly upregulated (P<0.05), whereas the expression of p-NF-κB p65, IL-1β, and TNF-α was significantly downregulated (P<0.05). ConclusionRMDHD increases tear secretion and TFBUT, improves lacrimal gland and corneal injury, and alleviates dry eye symptoms in a perimenopausal dry eye rat model with liver-kidney Yin deficiency syndrome. The underlying mechanism may be related to regulation of the SIRT3/HIF-1α/NF-κB signaling pathway, inhibition of oxidative stress and inflammatory responses, and reduction of ocular surface tissue damage.
4.Expert consensus on neoadjuvant PD-1 inhibitors for locally advanced oral squamous cell carcinoma (2026)
LI Jinsong ; LIAO Guiqing ; LI Longjiang ; ZHANG Chenping ; SHANG Chenping ; ZHANG Jie ; ZHONG Laiping ; LIU Bing ; CHEN Gang ; WEI Jianhua ; JI Tong ; LI Chunjie ; LIN Lisong ; REN Guoxin ; LI Yi ; SHANG Wei ; HAN Bing ; JIANG Canhua ; ZHANG Sheng ; SONG Ming ; LIU Xuekui ; WANG Anxun ; LIU Shuguang ; CHEN Zhanhong ; WANG Youyuan ; LIN Zhaoyu ; LI Haigang ; DUAN Xiaohui ; YE Ling ; ZHENG Jun ; WANG Jun ; LV Xiaozhi ; ZHU Lijun ; CAO Haotian
Journal of Prevention and Treatment for Stomatological Diseases 2026;34(2):105-118
Oral squamous cell carcinoma (OSCC) is a common head and neck malignancy. Approximately 50% to 60% of patients with OSCC are diagnosed at a locally advanced stage (clinical staging III-IVa). Even with comprehensive and sequential treatment primarily based on surgery, the 5-year overall survival rate remains below 50%, and patients often suffer from postoperative functional impairments such as difficulties with speaking and swallowing. Programmed death receptor-1 (PD-1) inhibitors are increasingly used in the neoadjuvant treatment of locally advanced OSCC and have shown encouraging efficacy. However, clinical practice still faces key challenges, including the definition of indications, optimization of combination regimens, and standards for efficacy evaluation. Based on the latest research advances worldwide and the clinical experience of the expert group, this expert consensus systematically evaluates the application of PD-1 inhibitors in the neoadjuvant treatment of locally advanced OSCC, covering combination strategies, treatment cycles and surgical timing, efficacy assessment, use of biomarkers, management of special populations and immune related adverse events, principles for immunotherapy rechallenge, and function preservation strategies. After multiple rounds of panel discussion and through anonymous voting using the Delphi method, the following consensus statements have been formulated: 1) Neoadjuvant therapy with PD-1 inhibitors can be used preoperatively in patients with locally advanced OSCC. The preferred regimen is a PD-1 inhibitor combined with platinum based chemotherapy, administered for 2-3 cycles. 2) During the efficacy evaluation of neoadjuvant therapy, radiographic assessment should follow the dual criteria of Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 and immune RECIST (iRECIST). After surgery, systematic pathological evaluation of both the primary lesion and regional lymph nodes is required. For combination chemotherapy regimens, PD-L1 expression and combined positive score need not be used as mandatory inclusion or exclusion criteria. 3) For special populations such as the elderly (≥ 70 years), individuals with stable HIV viral load, and carriers of chronic HBV/HCV, PD-1 inhibitors may be used cautiously under the guidance of a multidisciplinary team (MDT), with close monitoring for adverse events. 4) For patients with a poor response to neoadjuvant therapy, continuation of the original treatment regimen is not recommended; the subsequent treatment plan should be adjusted promptly after MDT assessment. Organ transplant recipients and patients with active autoimmune diseases are not recommended to receive neoadjuvant PD-1 inhibitor therapy due to the high risk of immune related activation. Rechallenge is generally not advised for patients who have experienced high risk immune related adverse events such as immune mediated myocarditis, neurotoxicity, or pneumonitis. 5) For patients with a good pathological response, individualized de escalation surgery and function preservation strategies can be explored. This consensus aims to promote the standardized, safe, and precise application of neoadjuvant PD-1 inhibitor strategies in the management of locally advanced OSCC patients.
5.Study on the mechanism of different concentrations of simvastatin on regeneration of sciatic nerve injury in rats
Yun-hu LI ; Jun-wei CAO ; Chen LI ; Jing-yu ZHANG ; Ai-she DUN ; Hong-bin WANG
Journal of Regional Anatomy and Operative Surgery 2025;34(9):772-775
Objective To explore the effects of different concentrations of simvastatin on nerve regeneration after sciatic nerve injury.Methods Rats were randomly divided into the normal group,the control group,the low-dose group and the high-dose group,with 3 rats in each group.Except for the normal group,adult rat sciatic nerve crush injury models were established in the other groups.Rats in the normal group and the control group were orally administered with water,while those in the low-dose group and high-dose group were orally administered with 98%simvastatin at dosages of 4 mg/mL and 40 mg/mL,respectively.The sciatic nerve regeneration in rats was evaluated by sciatic function index(SFI),HE staining,luxol fast blue(LFB)staining and immunofluorescence staining,etc.Results The SFI of rats in the high-dose group 7 days and 14 days after surgery were higher than those in the control group(P<0.05);there was no significant difference in SFI of rats between the low-dose group and the control group 7 days and 14 days after surgery(P>0.05).HE staining and LFB staining results showed that compared with the control group,the number of neurons of rats in the high-dose group increased,the nerve fibers and myelin were clearer and denser,and the nerve function was significantly restored;while no significant improvement was observed in the sciatic nerve of rats in the low-dose group.The immunofluorescence staining results showed that compared with the control group,the immunofluorescence intensity in the high-dose group increased,while that in the low-dose group decreased,the differences were statistically significant(P<0.05).Conclusion High-dose simvastatin can promote peripheral nerve regeneration by regulating the expression of M2 macrophages.
6.Guideline for Adult Weight Management in China
Weiqing WANG ; Qin WAN ; Jianhua MA ; Guang WANG ; Yufan WANG ; Guixia WANG ; Yongquan SHI ; Tingjun YE ; Xiaoguang SHI ; Jian KUANG ; Bo FENG ; Xiuyan FENG ; Guang NING ; Yiming MU ; Hongyu KUANG ; Xiaoping XING ; Chunli PIAO ; Xingbo CHENG ; Zhifeng CHENG ; Yufang BI ; Yan BI ; Wenshan LYU ; Dalong ZHU ; Cuiyan ZHU ; Wei ZHU ; Fei HUA ; Fei XIANG ; Shuang YAN ; Zilin SUN ; Yadong SUN ; Liqin SUN ; Luying SUN ; Li YAN ; Yanbing LI ; Hong LI ; Shu LI ; Ling LI ; Yiming LI ; Chenzhong LI ; Hua YANG ; Jinkui YANG ; Ling YANG ; Ying YANG ; Tao YANG ; Xiao YANG ; Xinhua XIAO ; Dan WU ; Jinsong KUANG ; Lanjie HE ; Wei GU ; Jie SHEN ; Yongfeng SONG ; Qiao ZHANG ; Hong ZHANG ; Yuwei ZHANG ; Junqing ZHANG ; Xianfeng ZHANG ; Miao ZHANG ; Yifei ZHANG ; Yingli LU ; Hong CHEN ; Li CHEN ; Bing CHEN ; Shihong CHEN ; Guiyan CHEN ; Haibing CHEN ; Lei CHEN ; Yanyan CHEN ; Genben CHEN ; Yikun ZHOU ; Xianghai ZHOU ; Qiang ZHOU ; Jiaqiang ZHOU ; Hongting ZHENG ; Zhongyan SHAN ; Jiajun ZHAO ; Dong ZHAO ; Ji HU ; Jiang HU ; Xinguo HOU ; Bimin SHI ; Tianpei HONG ; Mingxia YUAN ; Weibo XIA ; Xuejiang GU ; Yong XU ; Shuguang PANG ; Tianshu GAO ; Zuhua GAO ; Xiaohui GUO ; Hongyi CAO ; Mingfeng CAO ; Xiaopei CAO ; Jing MA ; Bin LU ; Zhen LIANG ; Jun LIANG ; Min LONG ; Yongde PENG ; Jin LU ; Hongyun LU ; Yan LU ; Chunping ZENG ; Binhong WEN ; Xueyong LOU ; Qingbo GUAN ; Lin LIAO ; Xin LIAO ; Ping XIONG ; Yaoming XUE
Chinese Journal of Endocrinology and Metabolism 2025;41(11):891-907
Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.
7.Expert Consensus on the Ethical Requirements for Generative AI-Assisted Academic Writing
You-Quan BU ; Yong-Fu CAO ; Zeng-Yi CHANG ; Hong-Yu CHEN ; Xiao-Wei CHEN ; Yuan-Yuan CHEN ; Zhu-Cheng CHEN ; Rui DENG ; Jie DING ; Zhong-Kai FAN ; Guo-Quan GAO ; Xu GAO ; Lan HU ; Xiao-Qing HU ; Hong-Ti JIA ; Ying KONG ; En-Min LI ; Ling LI ; Yu-Hua LI ; Jun-Rong LIU ; Zhi-Qiang LIU ; Ya-Ping LUO ; Xue-Mei LV ; Yan-Xi PEI ; Xiao-Zhong PENG ; Qi-Qun TANG ; You WAN ; Yong WANG ; Ming-Xu WANG ; Xian WANG ; Guang-Kuan XIE ; Jun XIE ; Xiao-Hua YAN ; Mei YIN ; Zhong-Shan YU ; Chun-Yan ZHOU ; Rui-Fang ZHU
Chinese Journal of Biochemistry and Molecular Biology 2025;41(6):826-832
With the rapid development of generative artificial intelligence(GAI)technologies,their widespread application in academic research and writing is continuously expanding the boundaries of sci-entific inquiry.However,this trend has also raised a series of ethical and regulatory challenges,inclu-ding issues related to authorship,content authenticity,citation accuracy,and accountability.In light of the growing involvement of AI in generating academic content,establishing an open,controllable,and trustworthy ethical governance framework has become a key task for safeguarding research integrity and maintaining trust within the academic community.This expert consensus outlines ethical requirements across key stages of AI-assisted academic writing-including topic selection,data management,citation practices,and authorship attribution.It aims to clarify the boundaries and ethical obligations surrounding AI use in academic writing,ensuring that technological tools enhance efficiency without compromising in-tegrity.The goal is to provide guidance and institutional support for building a responsible and sustainable research ecosystem.
8.Construction and Application Promotion of Core Medical Skills of"Tonifying Kidney Essence"in Zou's Nephrology Depart-ment
Gang WANG ; Yanqin ZOU ; Wei SUN ; Enchao ZHOU ; Lan YI ; Jun ZHU ; Wei KONG ; Jing ZHAO ; Liang CAO ; Hengbin WANG
Journal of Nanjing University of Traditional Chinese Medicine 2025;41(3):281-287
Professor Zou Yunxiang proposed the"kidney essence theory"in 1955,which believes that the kidney,as an important excretory organ in the human body,participates in the body's metabolism,and the basis for producing this effect is the essence of the kidney.Subsequently,the Zou nephrology team established the core medical technique of"tonifying the kidney element"based on this foundation,constructed a system of syndrome differentiation and treatment for chronic kidney disease,proposed the traditional Chinese medicine names,causes,and mechanisms of chronic kidney disease,as well as four major methods for diagnosing and treating chronic kidney disease,and developed representative drugs representing the core medical technique of"tonifying the kidney element"-Huang-zhi Yishen Capsules and Shenwu Yishen Tablets.In addition,the Zou nephrology team has extensively applied and promoted the core medical technique of"tonifying the kidney element".
9.Study on Improvement of Quantitative Capacity of Digital Droplet PCR by Double-Volume Droplets
Shan-Shan LI ; Yun-Liang CAO ; Xue-Yi ZHAO ; Jun-Wei LI
Chinese Journal of Analytical Chemistry 2025;53(7):1138-1145
Digital polymerase chain reaction(dPCR)enables absolute quantitative detection of nucleic acid samples.Since the quantitative upper and lower limits of detectable samples mainly depend on the volume and number of single droplets,the abundance of the sample to be tested,the volume of single droplets,and the number of droplets need to be adapted.For samples with unknown abundance,repeated adjustment of droplet size is not allowed.In this study,a one-step double-volume droplet generation method was proposed,and a double-volume droplet microfluidic chip was developed to verify the quantitative detection capability of the chip using a duck-derived kit.The results showed that the droplets with different volumes had different quantitative capabilities.Large-volume droplets had higher reliability for low-abundance sample concentrations,while small-volume droplets had advantages in detecting high-abundance sample concentrations.The double-volume droplets produced by the double-volume droplet microfluidic chip proposed in this study greatly improved the reliability of quantitative capabilities,and had broad application prospects in detection of precious nucleic acid samples with unknown abundance in the field of microfluidic PCR.
10.Highly Sensitive Detection of Sunset Yellow Using A Chitosan-Carbon Nanotube Electrochemical Sensor
Jun-Bin CAO ; Tian-Jin AO ; Kai-Kai NIU ; Jian-Wei ZHAO
Chinese Journal of Analytical Chemistry 2025;53(8):1259-1268
An electrochemical sensor based on a chitosan-carbon nanotube(CS-CNT)composite-modified glassy carbon electrode(GCE)was developed in this work for highly sensitive detection of sunset yellow(SY)in food.The CS-CNT composite dispersion was prepared via an ultrasonic dispersion method.Combined with quantum chemical calculations,the adsorption mechanism of SY molecules onto the electrode surface,facilitated by π-π conjugation and electrostatic interactions,was elucidated.The optimized experimental conditions were determined as follows:12 μL of CS-CNT dispersion modification volume,accumulation time of 300 s,and a phosphate buffer solution at pH 7.0 as supporting electrolyte solution.Experimental results demonstrated that CS significantly enhanced the dispersion of CNT,increasing the effective surface area of the modified electrode by 2.22 times(reaching 0.1587 cm2)compared to the bare GCE.The sensor exhibited a linear detection range of 3.0×10-7 mol/L to 1.0×10-5 mol/L,with a detection limit(S/N=3)of 5.0×10-10 mol/L.Satisfactory spiked recoveries ranging from 96.9%to 101.1%were achieved,along with good preparation reproducibility(relative standard deviation,RSD=4.96%).Interference tests indicated high selectivity of the sensor against citric acid,glucose,and common metal ions.The reliability of the sensor was validated through the detection of SY in actual beverage samples.This electrode design simplified operational procedures,avoiding cross-contamination between measurements,and provided an efficient solution for the on-site monitoring of food additives.


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