1.Dapagliflozin on acute kidney injury and prognosis in patients with diabetes mellitus type 2 and acute coronary syndrome after percutaneous coronary intervention
Huifang HAO ; Xiufeng ZHAI ; Qing LI ; Shicheng YANG ; Peng ZHANG
China Pharmacy 2025;36(4):469-474
OBJECTIVE To investigate the impact of dapagliflozin on contrast-induced acute kidney injury (CIAKI) and prognosis in patients with diabetes mellitus type 2 (T2DM) and acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI). METHODS Retrospective selection of data on T2DM patients with ACS who underwent PCI treatment in the Cardiology Department of Tianjin Chest Hospital from January 1st 2021 to December 31st 2022. The patients were divided into dapagliflozin group (96 cases) and control group (148 cases) based on whether they received dapagliflozin or not. Renal function indicators were measured for all enrolled patients before PCI and at 48 h and 1 week after PCI, including blood urea nitrogen (BUN), serum creatinine (Scr), estimated glomerular filtration rate (eGFR), cystatin-C (Cys-C), kidney injury molecule-1 (KIM-1) and β2-microglobulin (β2-MG). All patients were followed up for at least 1 year. The incidence of CIAKI and major adverse cardiac event (MACE) during follow-up were recorded for both groups. Logistic regression was used to analyze the impact of dapagliflozin on the occurrence of CIAKI, while the Log-rank test was applied to compare the incidence of MACE between the two groups. Cox regression was employed to analyze the impact of dapagliflozin on prognosis. RESULTS At 48 h and 1 week after PCI, serum levels of Cys-C, KIM-1 and β2-MG were significantly lower in the dapagliflozin group compared to the control group (P<0.05). The incidence of CIAKI was lower in the dapagliflozin group compared to the control group (6.25% vs. 14.86%, P=0.042). Logistic regression analysis revealed that dapagliflozin was an independent protective factor against CIAKI (OR=0.280, 95%CI 0.101-0.780,P=0.015). During the follow-up period, the incidence of MACE was lower in the dapagliflozin group compared to the control group (7.29% vs. 17.57%, P=0.049). Cox regression analysis indicated that dapagliflozin reduced the occurrence of MACE after PCI (HR=0.374, 95%CI 0.161-0.866, P=0.022). CONCLUSIONS With adequate hydration, the use of dapagliflozin does not increase the risk of CIAKI following PCI in T2DM patients with ACS.
2.Analysis of the basic situation of radiological diagnosis and treatment resources in medical institutions in Hunan Province, China
Zhenwei CAO ; Zhiyong XU ; Zipo ZHAI ; Junzhe PENG ; Donghui CHEN ; Yunfeng NIE
Chinese Journal of Radiological Health 2025;34(4):500-507
Objective To obtain the data of radiological diagnosis and treatment resource distribution at medical institutions of different levels and in various cities, understand the status of resource allocation, provide policy-making basis and suggestions for optimizing the allocation of radiological diagnosis and treatment resources within the province, and offer data and references for related research. Methods A basic situation questionnaire survey was conducted on radiological diagnosis and treatment institutions in Hunan Province. Data were reviewed, analyzed, and statistically processed using Excel software to understand the allocation situation of radiological diagnosis and treatment resources in Hunan Province. Results As of 2022, there were
3.Analyzing the heart-oriented view of the treatment of mental illness in Synopsis of Golden Chamber based on the theory of five-spirit-viscera
ZOU Peng ; Kai CHENG ; Minlong XIA ; Menghan LI ; Shuxian WANG ; Hui KONG ; Yan ZHAO ; Changming ZHAI ; Fang LU
Journal of Beijing University of Traditional Chinese Medicine 2025;48(4):495-500
Mental state is an important part of the normal life activities of the human body, and it is also the most external expression and the most easily obtained information of the physical condition. The normal activities of the mind depend on the normal operation of the viscera, qi, and blood, and are a unified whole that prospers together and suffers together. The theory of the five-spirit-viscera in the Yellow Emperor’s Inner Classic revealed that the normal mental activities of the human body were dominated by the five internal organs, that is, the five internal organs were the body and the five spirits were the function. And it highlighted the viewpoint that the five internal organs store the spirits and are actually one. The heart governs the spirit and belongs to the four internal organs. On this basis, Synopsis of Golden Chamber used the internal organs to diagnose and treat mental diseases, integrating the theory of the five spirits into it, forming a unique method of diagnosis and treatment with the heart as the leading factor and regulating the qi and blood of the four internal organs. It identified the pathogenesis of diseases such as pathogenic crying, lily disease, and hysteria from five levels: heart deficiency and weak qi, heart-lung disharmony, heart-liver disharmony, the heart of the loss of the spleen nourishment, and disharmony between heart and kidney. The treatment was mainly to replenish the deficiency of the viscera and eliminate the pathogens, reflecting the characteristics of regulating the mind and calming the four internal organs. This unique view on diagnosis and treatment has profoundly influenced the diagnosis and treatment theories of mental illnesses by later doctors, and is of great significance to the current clinical treatment of such illnesses.
4.The effects of Epimedium koreanum Nakai on liver function in rats with kidney yang deficiency and kidney yin deficiency pattern models based on the"You Gu Wu Yun"theory
Xiyi PENG ; Lin ZHANG ; Yuqi ZHAI ; Shuwei YU ; Yuan TIAN ; Zhaojuan GUO ; Song YANG ; Ting WANG
Journal of Beijing University of Traditional Chinese Medicine 2024;47(11):1562-1572
Objective This study explored the effects of Epimedium koreanum Nakai(EK)on liver function in normal,kidney yang deficiency(KYANGDS),and kidney yin deficiency(KYINDS)rats based on the theory of"You Gu Wu Yun."The study also investigated the connection between EK-induced liver injury and symptoms.Methods Seventy-two male SD rats were divided into normal,KYANGDS,and KYINDS groups using the random number table method.The KYANGDS model was established through intramuscular injection of 20 mg/kg of hydrocortisone,whereas the KYINDS model was established through daily gavage of 160 mg/kg of thyroid tablet suspension for 14 consecutive days.After successful modeling,the rats were divided into the normal,EK low-dose,EK high-dose,KYANGDS,KYANGDS+EK low-dose,KYANGDS+EK high-dose,KYINDS,KYINDS+EK low-dose,and KYINDS+EK high-dose groups using the random number table method.Animals in the drug groups were administered low(0.26 g/kg)and high(0.77 g/kg)EK extract doses through continuous gavage.The other groups received drinking water once a day for 28 consecutive days.Changes in body mass were monitored during the administration period,and serum alkaline phosphatase(ALP),alanine transaminase(ALT),aspartate transaminase(AST),direct bilirubin,indirect bilirubin(IBil),and total bilirubin(TBil)were measured at the end of administration using biochemical analyzers.The liver weight,visceral body ratio,and visceral brain ratio were measured.Hematoxylin and eosin staining were performed to observe the pathological changes in the liver.Results Compared with the normal group,the EK high-dose group showed a decrease in body weight on the 21st day during the drug administration period and an increase in IBil(P<0.05);the KYANGDS group had lower body weight at each measurement time point from the third to the 28th day,higher ALP,and lower liver weight(P<0.05).Compared with the KYANGDS group,the KYANGDS+EK high-dose group had decreased ALP levels(P<0.05).The pathological damage of liver tissue in each KYANGDS administration group improved,the presence of fat vacuoles were reduced,and pathological scores show a decreasing trend.Compared with the KYINDS group,KYINDS+EK high-dose group exhibited a higher IBil level and a lower visceral brain ratio(P<0.05).Conclusion EK has a small effect on the liver function of rats with KYANGDS within the dose range;however,it has a specific hepatogenic impact on normal and KYINDS rats,and EK-induced liver injury and the symptoms may be associated with each other.
5.Effects of Zhuangyao Shuanglu Tongnao Formula on neuronal apoptosis of rats with ischemia-reperfusion induced injury
Yang ZHAI ; Xue-Ni MO ; Hong-Li TENG ; Yue-Qiang HU ; Guang-Shan ZHENG ; Wei MA ; Peng YANG ; Xiao-Ping MEI ; Min ZOU ; Kai-Hua WANG
Chinese Traditional Patent Medicine 2024;46(3):795-802
AIM To investigate the effects of Zhuangyao Shuanglu Tongnao Formula on neuronal apoptosis in rats with cerebral ischemia-reperfusion injury based on the study of oxidative stress and inflammatory response.METHODS The rats were randomly divided into the sham operation group,the model group,the edaravone group(3.0 mg/kg),the low,medium and high dose groups(9.0,18.0,36.0 g/kg)of Zhuangyao Shuanglu Tongnao Formula,with 18 rats in each group.The middle cerebral artery occlusion/reperfusion was conducted by thread embolism method to simulate cerebral ischemia reperfusion injury in rats followed by 6 days corresponding drugs administration.Subsequently,the rats had their neurological function deficit scored by Zeal Longa scoring method;their sizes of cerebral infarction areas measured by TTC staining;their pathological damage and apoptosis of neurons in hippocampal CA1 area of ischemic penumbra of the brain tissue detected by HE staining and TUNEL staining;their SOD activity and levels of GSH,MDA,IL-6,IL-1β,TNF-α in brain tissue detected by kits;and their protein expressions of Bax,Bcl-2,caspase-3,cleaved-capase-3,TLR4,NF-κB p65,Nrf2,HO-1 in rat brain tissue determined by Western blot.RESULTS Compared with the model group,the groups intervened with edaravone,medium and high dose of Zhuangyao Shuanglu Tongnao Formula displayed improvements in the scores of nerve function defects,the rate of cerebral infarction,the rate of neuronal apoptosis,the levels of IL-6,IL-1β,TNF-α and MDA in the ischemic penumbra of brain tissues,the protein expressions of Bax and TLR4,the ratio of cleaved-capase-3/caspase-3 and p-NF-κB p65/NF-κB p65(P<0.05),the levels of GSH,the activity of SOD and the protein expressions of Bcl-2,Nrf2 and HO-1(P<0.05).CONCLUSION Being an inhibitor of oxidative stress and inflammatory response,Zhuangyao Shuanglu Tongnao Formula can alleviate brain injury in rats with cerebral ischemia reperfusion injury through the inhibition of neuronal apoptosis and improvement of neural function mediated by the inhibition of TLR4/NF-κB signal pathway and activation of Nrf2/HO-1 signal pathway.
6.PENG Peichu's Experience in Staged Differentiation and Treatment of Prostate Cancer
Xinyu XU ; Yu PENG ; Wenjing ZHU ; Jing ZHAI ; Dongya SHENG ; Mingyang WANG ; Yiqun SHAO ; Boyang LI ; Qi ZHONG
Journal of Traditional Chinese Medicine 2024;65(7):678-683
This paper summarized Professor PENG Peichu's experience in the differentiation and treatment of prostate cancer in three phases and four stages. It is considered that prostatic cancer is categorized into root deficiency and branch excess, with depletion of healthy qi as the root, and the accumulation of cancer toxin as the minifestation. Clinical diagnosis and treatment of prostatic cancer can be divided into three phases and four stages according to the exuberance and decline of pathogenic and healthy qi and the changes of deficiency and excess of yin and yang. In the initial accumulation phase of cancer toxin (yang excess stage), the key pathogenesis is the accumulation of dampness, heat and static blood, and internal generation of cancer toxin, and the treatment should be resolving toxins, fighting cancer and dispelling yang excess. In the phase of healthy qi deficiency and toxin accumulation (yin deficiency stage), with the lung and kidney yin deficiency, dampness, heat and static toxin accumulation as the key pathogenesis, the treatment should be centered on mutual generation between metal and water to nourish kidney yin, supplemented with the method of clearing heat and draining dampness, activating blood and resolving toxins, for which self-made Nanbei Formula(南北方)is usually used. In the phase of yang deficiency and cold stagnation (yang deficiency stage and yin excess stage), with the spleen and kidney yang deficiency, cold dampness stagnation, static heat and toxin accumulation as the key pathogenesis, the treatment should be warming and tonifying spleen and kidney to dissipate cold accumulation; for deficiency of both yin and yang, and excess pathogen obstruction, modified Yanghe Decoction(阳和汤) is recommended, while for yang deficiency, cold congealing and blood stasis, self-made Wenshen Sanjie Formula(温肾散结方) can be used, and for cold dampness binding with cancer toxin, and cold complex with heat, self-made Quanan Formula (泉安方) is advised.
7.Analysis of the efficacy and safety of preoperative programmed death protein-1 inhibitor combined with chemotherapy in immunotherapy-sensitive patients with locally advanced gastric cancer or adenocarcinoma of the esophagogastric junction
Yingjie LI ; Peng YUAN ; Jianning ZHAI ; Yunfeng YAO ; Luxin TAN ; Zhongwu LI ; Xiaoyan ZHANG ; Aiwen WU
Chinese Journal of Gastrointestinal Surgery 2024;27(7):684-693
Objective:To evaluate the short-term efficacy and safety of a preoperative combination of programmed cell death protein-1 (PD-1) inhibitor with either oxaliplatin + capecitabine (CapeOx) or oxaliplatin + tegafur gimeracil oteracil potassium (SOX) in the treatment of locally advanced immunotherapy-sensitive gastric cancer (LAGC) or adenocarcinoma of the esophagogastric junction (AEG).Methods:The cohort of this retrospective descriptive case series comprised patients with LAGC or AEG whose cancers had been determined to be immunotherapy- sensitive by endoscopic biopsy before treatment in the Gastrointestinal Cancer Center, Unit III, Peking University Cancer Hospital and Institute from 1 August 1 2021 to 31 January 2024. Patients with any one of the following three characteristics were immunotherapy-sensitive: (i) PD-L1 combined positive score (CPS) ≥5; (ii) microsatellite instability-high (MSI-H) / mismatch repair deficiency (dMMR); or (iii) Epstein-Barr virus-encoded RNA (EBER) positivity. All study patients received PD-1 inhibitors combined with CapeOx or SOX as a neoadjuvant or conversion treatment strategy before surgery. Patients with immune system diseases, distant metastases, or human epidermal growth factor receptor 2 positivity were excluded. Factors analyzed included pathological complete response, clinical complete response, major pathological response, R0 resection rate, surgical conversion rate, and safety of the treatment, including immune-related adverse events (irAEs) and surgical complications.Results:The study cohort comprised 39 patients (28 men and 11 women) of median age 62 (range 44–79) years. After the above-described preoperative treatment, radical resection of the 14 tumors that were initially considered unresectable was achieved (surgical conversion rate: 14/14). Twenty-three of the remaining 25 patients underwent radical resection. The last two patients achieved clinical complete responses and opted for a "non-surgical strategy" (watch and wait). Overall, 37 patients (94.9%) underwent radical resection, with an R0 resection rate of 100% (37/37), pathological complete response rate of 48.6% (18/37), and major pathological response rate of 62.2% (23/37). Of the 24 patients with CPS ≥ 5 (non-MSI-H/dMMR and non-EBER positive), 11 achieved pathological complete responses and one with CPS=95 achieved a clinical complete response. Of the eight patients with MSI-H/dMMR, six achieved pathological complete responses and one a clinical complete response. Of the seven patients with EBER positivity, one achieved a pathological complete response. After excluding patients with major pathological complete responses, there was a statistically significant difference in CPS scores between preoperative biopsy specimens and postoperative surgical specimens in 13 patients (7.769±5.570 vs. 15.538±16.870, t=2.287, P=0.041). All patients tolerated preoperative immunotherapy well; nine patients (9/39, 23.1%) had Grade I–II irAEs. There were no Grade III–IV irAEs. The five patients with pyloric obstruction before treatment tolerated normal diets after treatment. The incidence of postoperative complications among all patients who underwent surgery was 18.9% (7/37), including one case of Grade IIIA anastomotic leakage, one of Grade IIIA intestinal obstruction, one of Grade II abdominal hemorrhage, two of Grade II abdominal infection, one of Grade I intestinal obstruction. Additionally, one patient developed COVID-19 postoperatively. All patients recovered with symptomatic treatment. Conclusion:We found that preoperative treatment of patients with LAGC or AEG of one of three types (CPS≥5, dMMR+MSI-H, and EBER positivity) with a PD-1 inhibitor combined with CapeOx or SOX chemotherapy achieved promising effectiveness and safety, with high surgical conversion, R0 resection, and complete response rates.
8.Prognosis and its influencing factors in patients with non-gastric gastrointestinal stromal tumors at low risk of recurrence: a retrospective multicenter study in China
Linxi YANG ; Weili YANG ; Xin WU ; Peng ZHANG ; Bo ZHANG ; Junjun MA ; Xinhua ZHANG ; Haoran QIAN ; Ye ZHOU ; Tao CHEN ; Hao XU ; Guoli GU ; Zhidong GAO ; Gang ZHAI ; Xiaofeng SUN ; Changqing JING ; Haibo QIU ; Xiaodong GAO ; Hui CAO ; Ming WANG
Chinese Journal of Gastrointestinal Surgery 2024;27(11):1123-1132
Objective:To investigate the prognosis and the factors that influence it in patients with non-gastric gastrointestinal stromal tumors (GISTs) who are at low risk of recurrence.Methods:This was a retrospective cohort study. Clinicopathologic and prognostic data from patients with non-gastric GISTs and at low risk of recurrence (i.e., very low-risk or low-risk according to the 2008 version of the Modified NIH Risk Classification), who attended 18 medical centers in China between January 2000 and June 2023, were collected. We excluded patients with a history of prior malignancy, concurrent primary malignancy, multiple GISTs, and those who had received preoperative imatinib. The study cohort comprised 1,571 patients with GISTs, 370 (23.6%) of whom were at very low-risk and 1,201 (76.4%) at low-risk of recurrence. The cohort included 799 (50.9%) men and 772 (49.1%) women of median age 57 (16–93) years. Patients were followed up to July 2024. The prognosis and its influencing factors were analyzed. Receiver operating characteristic curves for tumor diameter and Ki67 were established, and the sensitivity, specificity, area under the curve (AUC) and optimal cut-off value with 95% confidence intervals were calculated. Propensity score matching was implemented using the 1:1 nearest neighbor matching method with a matching tolerance of 0.02.Results:With a median follow-up of 63 (12–267) months, the 5- and 10-year overall survival (OS) rates of the 1,571 patients were 99.5% and 98.0%, respectively, and the 5- and 10-year disease-free survival (DFS) rates were 96.3% and 94.4%, respectively. During postoperative follow-up, 3.8% (60/1,571) patients had disease recurrence or metastasis, comprising 0.8% (3/370) in the very low-risk group and 4.7% (57/1,201) in the low-risk group. In the low-risk group, recurrence or metastasis occurred in 5.5% (25/457) of patients with duodenal GISTs, 3.9% (25/645) of those with small intestinal GISTs, 9.2% (6/65) of those with rectal GISTs, and 10.0% (1/10) of those with colonic GISTs. Among the 60 patients with metastases, 56.7% (34/60) of the metastases were located in the abdominal cavity, 53.3% (32/60) in the liver, and 3.3% (2/60) in bone. During the follow-up period, 13 patients (0.8%) died of disease. Receiver operating characteristic curves were plotted for tumor diameter and Ki67 and assessed using the Jordon index. This showed that the difference in DFS between the two groups was statistically significant when the cutoff value for tumor diameter was 3.5 cm (AUC 0.731, 95% CI: 0.670–0.793, sensitivity 77.7%, specificity 64.1%). Furthermore, the difference in DFS between the two groups was statistically significant when the cutoff value for Ki67 was 5% (AUC 0.693, 95% CI: 0.624–0.762, sensitivity 60.7%, specificity 65.3%). Multifactorial analysis revealed that tumor diameter ≥3.5 cm, Ki67 ≥5%, and R1 resection were independent risk factors for DFS in patients with non-gastric GISTs at low risk of recurrence (all P<0.05). Furthermore, age >57 years, Ki67 ≥5%, and R1 resection were also independent risk factors for OS in patients with non-gastric GISTs at low risk of recurrence (all P<0.05). We also grouped the patients according to whether they had received postoperative adjuvant treatment with imatinib for 1 or 3 years. This yielded 137 patients in the less than 1-year group, 139 in the 1-year plus group; and 44 in both the less than 3 years and 3-years plus group. After propensity score matching for age, tumor diameter, Ki67, and resection status, the differences in survival between the two groups were not statistically significant (all P>0.05). The 10-year DFS and OS were 87.5% and 95.5%, respectively, in the group treated with imatinib for less than 1 year and 88.5% and 97.8%, respectively, in the group treated for more than 1 year. The 10-year DFS and OS were 89.6% and 92.6%, respectively, in the group treated with imatinib for less than 3 years and 88.0% and 100.0%, respectively, in the group treated with imatinib for more than 3 years. Conclusion:The overall prognosis of primary, non-gastric, low recurrence risk GISTs is relatively favorable; however, recurrences and metastases do occur. Age, tumor diameter, Ki67, and R1 resection may affect the prognosis. For some patients with low risk GISTs, administration of adjuvant therapy with imatinib for an appropriate duration may help prevent recurrence and improve survival.
9.Effect of Shuanglu Tongnao Formula on Neuronal Ferroptosis in Ischemic Stroke Rats by Regulating the SIRT1/Nrf2/GPx4 Signaling Pathway
Guangshan ZHENG ; Yang ZHAI ; Kaihua WANG ; Wei MA ; Xiaoping MEI ; Ying CHEN ; Min ZOU ; Yan PANG ; Peng YANG ; Yan LYU
Herald of Medicine 2024;43(4):526-534
Objective To explore the effect of Shuanglu Tongnao Formula on neuronal ferroptosis in ischemic stroke rats and its regulatory mechanism on the silent information regulator 2 homolog 1(SIRT1)/nuclear factor erythroid 2-related fac-tor 2(Nrf2)/glutathione peroxidase 4(GPx4)signaling pathways.Methods Twenty rats were selected as sham operation group by the random number table method,and the remaining seventy rats were made ischemic stroke rat models by the middle cerebral artery occlusion method.The rats that had been successfully modeled were randomly divided into the model control group,Shuanglu Tongnao formula group,Shuanglu Tongnao formula+SIRT1 inhibitor group(Shuanglu Tongnao formula+EX527 group),with 20 rats in each group.After 14 days,the rats were scored for neurological injury;TTC staining was applied to detect the area of cerebral infarction in rats;HE staining was applied to detect pathological changes in rat brain tissue;Nissl staining was applied to detect the number of neurons in rat brain tissue;the kit was applied to detect the levels of ferri ion(Fe2+),superoxide dismutase(SOD),glutathione(GSH),and malonaldehyde(MDA)in rat brain tissue;immunohistochemistry was applied to de-tect the positive expression of acyl-CoA synthetase long-chain family member 4(ACSL4),transferrin receptor(TFR),and ferritin heavy polypeptide 1(FTH1)proteins in rat brain tissue;Western blotting method was applied to detect the expression of SIRT1,Nrf2,GPx4,and cystine/glutamate antiporter solute carrier family 7 member 11(SLC7A11)proteins in rat brain tissue.Results Compared with the sham operation group,the neurological deficit score,cerebral infarction area,the contents of Fe2+and MDA,and the protein expressions of ACSL4 and TFR in model control group were increased(P<0.05);the number of neurons,the con-tents of SOD and GSH,the protein expression of FTH1,SIRT1,Nrf2,GPx4,and SLC7A11 were all reduced(P<0.05).Compared with the model control group,the neurological deficit score,cerebral infarction area,the contents of Fe2+and MDA,and the protein expression of ACSL4 and TFR in the Shuanglu Tongnao formula group were reduced(P<0.05),and the number of neurons,the contents of SOD and GSH,the protein expressions of FTH1,SIRT1,Nrf2,GPx4,and SLC7A11 are all increased(P<0.05).The results of the SIRT1 inhibitor supplementation experiment showed that the SIRT1 inhibitor reversed the inhibitory effect of Shuan-glu Tongnao formula on neuronal ferroptosis,while also inhibited the expression of Nrf2 and GPx4(P<0.05).Conclusion The Shuanglu Tongnao formula may inhibit neuronal ferroptosis in ischemic stroke rats by activating the SIRT1/Nrf2/GPx4 signa-ling pathway.
10.Research on Electrochemical Chemical Oxygen Demand Sensor
Shan YUN ; Lei WANG ; Li-Guo WAN ; Zhen-Yu PENG ; Hong-Chang WANG ; Jun-Feng ZHAI ; Shao-Jun DONG
Chinese Journal of Analytical Chemistry 2024;52(9):1298-1306
An electrochemical chemical oxygen demand(COD)sensor was proposed based on a FTO/TiO2/PbO2 electrode and a thin-layer electrochemical cell.The FTO/TiO2/PbO2 electrode was characterized by X-ray photoelectronic spectroscopy(XPS),X-ray diffraction(XRD)spectroscopy and electrochemical technique,and the results indicated that the rapid decrease in the output signals of the electrochemical COD sensor could be attributed to oxidation of PbSO4 occurring on the surface of FTO/TiO2/PbO2 electrode.The PbO2 deposition time and concentration of Na2SO4 were further optimized and then the electrochemical COD sensor was challenged by real samples including laker water sample,river water sample and wastewater sample.The evolution trend of signals of the electrochemical COD sensor in response to lake and river water samples was identical with that obtained with the standard method(HJ/T399-2007,Water quality-determination of the chemical oxygen demand-fast digestion-spectrophotometric method).The electrochemical COD sensor exhibited significant increase in the signal intensity after the samples were switched from lake water to wastewater sample,and a mean value of 32.5 mg/L with relative standard deviation(RSD)of 6.8%were obtained after measuring 45 times the wastewater with COD value of 30 mg/L under a sampling interval of 400 s.The as-prepared electrochemical COD sensor possessed good promise in regular monitoring of COD,discharge of wastewater and industrial process control,with advantages such as a small sampling interval,mild reaction conditions and no requirement of toxic and harmful chemical reagents.


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