1.Influencing factors of enlarged perivascular spaces in relapsing-remitting multiple sclerosis patients and their association with cognitive impairment
Zhihong LI ; Chaohui WANG ; Jing HAN ; Runhua BAI ; Yudan LIU ; Xue ZHANG ; Qingjun WANG ; Jianguo LIU
Chinese Journal of Neurology 2025;58(6):615-623
Objective:To investigate the influencing factors of enlarged perivascular space (PVS) in relapsing-remitting multiple sclerosis (RRMS) patients and their relationship with cognitive function.Methods:Twenty-seven individuals with RRMS (RRMS group) and 27 healthy controls (healthy control group) who presented to the Department of Neurology, the Sixth Medical Center of People′s Liberation Army General Hospital from July 2022 to November 2024 underwent cognitive function assessments. PVS volume fractions, lesion volumes, and brain volumes were calculated using FreeSurfer, FSL, and other relevant softwares. Group differences in PVS volume fractions, lesion volumes, brain volumes, and cognitive function assessments were compared. Furthermore, correlations between PVS volume fractions and lesion volumes, brain volumes, and cognitive function assessments were analyzed within the RRMS group.Results:Compared with the healthy control group, the RRMS group exhibited significantly higher PVS volume fractions in white matter (PVS_w) (3.14‰±0.29‰ vs 2.91‰±0.30‰, t=2.877, P=0.006) and PVS volume fractions in deep gray matter (PVS_d) (2.25‰±0.10‰ vs 2.17‰±0.09‰, t=2.681, P=0.010), indicating an enlargement of the PVS. Compared with the healthy control group, the RRMS group showed a significant decrease in both white matter volumes [297.3 (274.3, 340.2) ml vs (324.2 (311.0, 350.0) ml, U=-2.085, P=0.037] and deep grey matter volumes [40.2 (34.9, 43.6) ml vs 42.7 (40.2, 44.8) ml, U=-2.292, P=0.022]. Compared with the healthy control group, the RRMS group showed significantly lower scores in cognitive function assessments ( P<0.05). Univariate analysis showed that PVS_w in the RRMS group was significantly positively correlated with age ( r=0.486), white matter lesion volumes ( r=0.437) and deep gray matter lesion volumes ( r=0.394;all P<0.05); PVS_d was also significantly positively correlated with white matter lesion volumes ( r=0.418) and deep gray matter lesion volumes ( r=0.480; both P<0.05). Multiple linear regression analysis showed that age ( B=0.011,95% CI 0.004-0.017), white matter lesion volumes ( B=0.026,95% CI 0.011-0.040) and deep gray matter lesion volumes ( B=0.401,95% CI 0.032-0.771) in the RRMS group were significantly positively correlated with PVS_w, while white matter lesion volumes ( B=0.007,95% CI 0.001-0.014) and deep gray matter lesion volumes ( B=0.204,95% CI 0.029-0.380) were significantly positively correlated with PVS_d (both P<0.05). Univariate analysis showed that immediate memory score in the RRMS group was significantly negatively correlated with PVS_d ( r=-0.428), and was significantly positively correlated with education level ( r=0.471), deep gray matter volumes ( r=0.530) and total brain volumes ( r=0.389; all P<0.05); short-term delayed memory score in the RRMS group was significantly negatively correlated with age ( r=-0.390), PVS_w ( r=-0.417) and white matter lesion volumes ( r=-0.438), and was significantly positively correlated with gender ( r=0.393), white matter volumes ( r=0.478), deep gray matter volumes ( r=0.579) and total brain volumes ( r=0.602;all P<0.05); verbal fluency test score in the RRMS group was significantly negatively correlated with PVS_d ( r=-0.409) and was significantly positively correlated with education level ( r=0.419) and total brain volumes ( r=0.400;all P<0.05). Multiple linear regression analysis revealed that PVS_d ( B=-5.572, 95% CI -11.513--0.368) and brain volumes ( B=0.012, 95% CI 0.001-0.023) in the RRMS group were both significant predictors of immediate recall score, while PVS_d ( B=-14.203,95% CI -27.514--0.891) was an independent predictor of verbal fluency test score (all P<0.05). Conclusions:The PVS is enlarged in individuals with RRMS compared with the healthy controls, and increased lesion volumes may be a significant predictor. Furthermore, enlarged PVS in the deep gray matter may be a significant predictor of impairment of verbal memory and verbal function in individuals with RRMS.
2.Influencing factors of enlarged perivascular spaces in relapsing-remitting multiple sclerosis patients and their association with cognitive impairment
Zhihong LI ; Chaohui WANG ; Jing HAN ; Runhua BAI ; Yudan LIU ; Xue ZHANG ; Qingjun WANG ; Jianguo LIU
Chinese Journal of Neurology 2025;58(6):615-623
Objective:To investigate the influencing factors of enlarged perivascular space (PVS) in relapsing-remitting multiple sclerosis (RRMS) patients and their relationship with cognitive function.Methods:Twenty-seven individuals with RRMS (RRMS group) and 27 healthy controls (healthy control group) who presented to the Department of Neurology, the Sixth Medical Center of People′s Liberation Army General Hospital from July 2022 to November 2024 underwent cognitive function assessments. PVS volume fractions, lesion volumes, and brain volumes were calculated using FreeSurfer, FSL, and other relevant softwares. Group differences in PVS volume fractions, lesion volumes, brain volumes, and cognitive function assessments were compared. Furthermore, correlations between PVS volume fractions and lesion volumes, brain volumes, and cognitive function assessments were analyzed within the RRMS group.Results:Compared with the healthy control group, the RRMS group exhibited significantly higher PVS volume fractions in white matter (PVS_w) (3.14‰±0.29‰ vs 2.91‰±0.30‰, t=2.877, P=0.006) and PVS volume fractions in deep gray matter (PVS_d) (2.25‰±0.10‰ vs 2.17‰±0.09‰, t=2.681, P=0.010), indicating an enlargement of the PVS. Compared with the healthy control group, the RRMS group showed a significant decrease in both white matter volumes [297.3 (274.3, 340.2) ml vs (324.2 (311.0, 350.0) ml, U=-2.085, P=0.037] and deep grey matter volumes [40.2 (34.9, 43.6) ml vs 42.7 (40.2, 44.8) ml, U=-2.292, P=0.022]. Compared with the healthy control group, the RRMS group showed significantly lower scores in cognitive function assessments ( P<0.05). Univariate analysis showed that PVS_w in the RRMS group was significantly positively correlated with age ( r=0.486), white matter lesion volumes ( r=0.437) and deep gray matter lesion volumes ( r=0.394;all P<0.05); PVS_d was also significantly positively correlated with white matter lesion volumes ( r=0.418) and deep gray matter lesion volumes ( r=0.480; both P<0.05). Multiple linear regression analysis showed that age ( B=0.011,95% CI 0.004-0.017), white matter lesion volumes ( B=0.026,95% CI 0.011-0.040) and deep gray matter lesion volumes ( B=0.401,95% CI 0.032-0.771) in the RRMS group were significantly positively correlated with PVS_w, while white matter lesion volumes ( B=0.007,95% CI 0.001-0.014) and deep gray matter lesion volumes ( B=0.204,95% CI 0.029-0.380) were significantly positively correlated with PVS_d (both P<0.05). Univariate analysis showed that immediate memory score in the RRMS group was significantly negatively correlated with PVS_d ( r=-0.428), and was significantly positively correlated with education level ( r=0.471), deep gray matter volumes ( r=0.530) and total brain volumes ( r=0.389; all P<0.05); short-term delayed memory score in the RRMS group was significantly negatively correlated with age ( r=-0.390), PVS_w ( r=-0.417) and white matter lesion volumes ( r=-0.438), and was significantly positively correlated with gender ( r=0.393), white matter volumes ( r=0.478), deep gray matter volumes ( r=0.579) and total brain volumes ( r=0.602;all P<0.05); verbal fluency test score in the RRMS group was significantly negatively correlated with PVS_d ( r=-0.409) and was significantly positively correlated with education level ( r=0.419) and total brain volumes ( r=0.400;all P<0.05). Multiple linear regression analysis revealed that PVS_d ( B=-5.572, 95% CI -11.513--0.368) and brain volumes ( B=0.012, 95% CI 0.001-0.023) in the RRMS group were both significant predictors of immediate recall score, while PVS_d ( B=-14.203,95% CI -27.514--0.891) was an independent predictor of verbal fluency test score (all P<0.05). Conclusions:The PVS is enlarged in individuals with RRMS compared with the healthy controls, and increased lesion volumes may be a significant predictor. Furthermore, enlarged PVS in the deep gray matter may be a significant predictor of impairment of verbal memory and verbal function in individuals with RRMS.
3.Research of miR-29a on TGF-β1/Smad3 pathway in pulmonary fibrosis induced by neodymium oxide
Chinese Journal of Industrial Hygiene and Occupational Diseases 2024;42(1):10-15
Objective:To exploring the regulatory effect of miR-29a on the transforming growth factor-β1 (TGF-β1) /Smad homolog 3 (Smad3) pathway during the process of rare earth neodymium oxide (Nd 2O 3) induced pulmonary fibrosis in mice. Methods:In March 2021, 72 SPF grade C57/BL6J male mice were selected and randomly divided into a control group, Nd 2O 3 group, Nd 2O 3+miR-29a agomir group, and Nd 2O 3+NC agomir group, with 18 mice in each group. The Nd 2O 3 group, Nd 2O 3+miR-29a agomir group, and Nd 2O 3+NC agomir group were treated with non exposed tracheal instillation, with a dust concentration of 250 mg/ml and a dust volume of 0.1 ml. The control group was given the same volume of physiological saline. After exposure to Nd 2O 3, 0.1 ml (5 nmol) of miR-29a agomir was injected into the tail vein of mice in the Nd 2O 3+miR-29a agomir group every 3 days, while 0.1 ml of NC agomir was injected into the tail vein of mice in the Nd 2O 3+NC agomir group. On the 7 th, 14 th, and 28 th days after dust exposure, 6 mice were killed in each group, and the lung tissue of the mice was taken out. HE staining was used to observe the pathological status of the mouse lung tissue; ELISA method was used to detect the levels of TGF-β1 and connective tissue growth factor (CTGF) in lung tissue; Use qRT-PCR detection method to detect the expression level of TGF-β1 mRNA; Using immunofluorescence assay to detect the expression level of Smad3 in mouse lung tissue; Use bioinformatics websites such as TargetScan7 and miRDB to predict the target gene of miR-29a. When the metrological date were satisfied with normal distribution, Mean±SD was used for comparison between groups, t test was used for two indepent samples, and LSD method was used when the variance was homogeneity in pairwise comparison. Results:HE staining showed that the Nd 2O 3 group of mice showed obvious infiltration of inflammatory cells and structural disorder of alveoli in the early stage of lung tissue. At 28 days, the collagen fibers in the mouse lung tissue increased and the lung tissue showed fibrotic honeycomb like changes. The degree of pulmonary fibrosis in the Nd 2O 3+miR-29a agomir group of mice was significantly reduced; The content of TGF-β1 and CTGF in the lung tissue of mice in the Nd 2O 3+miR-29a agomir group was lower than that in the Nd 2O 3+NC agomir group ( P<0.05) ; The relative expression level of TGF-β1 in the lung tissue of mice in the Nd 2O 3+miR-29a agomir group was lower than that in the Nd 2O 3+NC agomir group ( P<0.05) ; The expression level of Smad3 in the nucleus of the Nd 2O 3+miR-29a agomir group was lower than that of the Nd 2O 3+NC agomir group ( P<0.05). The prediction results of bioinformatics websites have found 152 downstream target genes related to miR-29a, among which FBN1, MAP2K6, KPNB1, COL1A2, SNIP1, LAMC1, and SP1 genes may be related to the regulatory effect of miR-29a on TGF-β1/Smad3 signaling pathway. Conclusion:miR-29a may affect lung fibrosis induced by rare earth Nd 2O 3 exposure in mice by regulating TGF-β1/Smad3 signaling pathway. Overexpression of miR-29a may inhibit TGF-β1/Smad3 signaling pathway and reduce the degree of pulmonary fibrosis in mice.
4.Exploration of detection methods for free silica with different crystal forms in dust
Qi GENG ; Chaoyang WANG ; Chengming MENG ; Zixin HE ; Liu YANG ; Yudan ZHANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2024;42(3):180-183
Objective:To investigate the differences and applicability of free silica detection methods of different crystal forms in dust, and to provide a basis for the selection of various methods.Methods:From December 2021 to June 2022, dust samples from 20 enterprises in different industries in 18 cities in Henan Province were randomly selected as the investigation objects. X-ray diffraction (XRD) method was used to analyze the samples and classify the samples. Based on GBZ/T 192.4-2007 "Determination of Dust in the Air of Workplace-Part 4: Content of Free Silica in Dust", pyrophosphate method and infrared spectrophotometry were used for quantitative determination. The measured results were analyzed by paired sample t test to evaluate the advantages and disadvantages of the two methods and their applicable scope. Results:The XRD results of 20 dust samples could be divided into α, β, γ crystal types and the mixed type of α and γ. There was no significant difference between pyrophosphate method and infrared spectrophotometry ( P=0.180). The pyrophosphate method results of β, γ and α, γ mixed crystalline free silica were significantly higher than those of infrared spectrophotometry, and the difference was statistically significant ( P<0.001) . Conclusion:Pyrophosphate method and infrared spectrophotometry are suitable for α-type free silica, while pyrophosphate method is suitable for β, γ and α, γ mixed crystalline free silica.
5.Viral etiology and prognosis of severe acute respiratory tract infection in out-patient children under 5 years of age
Xue WANG ; Jun WEN ; Yufei SU ; Yudan ZHANG
Journal of Chinese Physician 2024;26(12):1798-1802
Objective:To investigate the etiology and prognosis of severe acute respiratory infection (SARI) in <5 year old outpatients.Methods:The data of 199 children with SARI admitted to the outpatient department of the Xi′an Children′s Hospital from January 2022 to December 2023 were included. Nasopharyngeal swabs were collected and the etiology of SARI virus in children was determined by polymerase chain reaction (PCR) within 48 h of study inclusion. The factors influencing respiratory support and length of stay in SARI children were analyzed by multiple linear regression.Results:Among the 199 patients included, 183 patients had positive nasopharyngeal swabs, with a positive rate of 92.0%. One pathogen was found in 124(62.3%) positive patients, two pathogens were found in 53(26.6%) positive patients, and three pathogens were found in 6(3.0%) positive patients. The most commonly detected viruses were rhinovirus (42.7%, 85/199), respiratory syncytial virus (33.2%, 66/199) and parainfluenza virus (14.1%, 28/199). Respiratory syncytial virus was detected in 40(54.8%) of the samples collected from infants aged 0 to 6 months, significantly higher than the frequency found in other age groups ( P<0.05). Adenoviruses were more common in the >12-24 month age group (22.0%). Age-specific weight Z score ( β=-0.223, 95% CI=-1.042--0.136, P=0.011) and SpO 2 ( β=-0.237, 95% CI=-0.21--0.037, P=0.006) were the influencing factors for respiratory support days in children with SARI. Age-specific weight Z score ( β=-0.223, 95% CI=-1.049--0.124, P=0.013) and SpO 2 ( β=-0.209, 95% CI=-0.204--0.020, P=0.017) were the factors influencing the length of hospital stay in SARI children. Conclusions:The findings of this study highlight the importance of viruses as SARI-associated pathogens in this population. Children at risk of a severe course of disease can be identified by measuring their age-specific weight Z score and SpO 2 on admission.
6.Research of miR-29a on TGF-β1/Smad3 pathway in pulmonary fibrosis induced by neodymium oxide
Chinese Journal of Industrial Hygiene and Occupational Diseases 2024;42(1):10-15
Objective:To exploring the regulatory effect of miR-29a on the transforming growth factor-β1 (TGF-β1) /Smad homolog 3 (Smad3) pathway during the process of rare earth neodymium oxide (Nd 2O 3) induced pulmonary fibrosis in mice. Methods:In March 2021, 72 SPF grade C57/BL6J male mice were selected and randomly divided into a control group, Nd 2O 3 group, Nd 2O 3+miR-29a agomir group, and Nd 2O 3+NC agomir group, with 18 mice in each group. The Nd 2O 3 group, Nd 2O 3+miR-29a agomir group, and Nd 2O 3+NC agomir group were treated with non exposed tracheal instillation, with a dust concentration of 250 mg/ml and a dust volume of 0.1 ml. The control group was given the same volume of physiological saline. After exposure to Nd 2O 3, 0.1 ml (5 nmol) of miR-29a agomir was injected into the tail vein of mice in the Nd 2O 3+miR-29a agomir group every 3 days, while 0.1 ml of NC agomir was injected into the tail vein of mice in the Nd 2O 3+NC agomir group. On the 7 th, 14 th, and 28 th days after dust exposure, 6 mice were killed in each group, and the lung tissue of the mice was taken out. HE staining was used to observe the pathological status of the mouse lung tissue; ELISA method was used to detect the levels of TGF-β1 and connective tissue growth factor (CTGF) in lung tissue; Use qRT-PCR detection method to detect the expression level of TGF-β1 mRNA; Using immunofluorescence assay to detect the expression level of Smad3 in mouse lung tissue; Use bioinformatics websites such as TargetScan7 and miRDB to predict the target gene of miR-29a. When the metrological date were satisfied with normal distribution, Mean±SD was used for comparison between groups, t test was used for two indepent samples, and LSD method was used when the variance was homogeneity in pairwise comparison. Results:HE staining showed that the Nd 2O 3 group of mice showed obvious infiltration of inflammatory cells and structural disorder of alveoli in the early stage of lung tissue. At 28 days, the collagen fibers in the mouse lung tissue increased and the lung tissue showed fibrotic honeycomb like changes. The degree of pulmonary fibrosis in the Nd 2O 3+miR-29a agomir group of mice was significantly reduced; The content of TGF-β1 and CTGF in the lung tissue of mice in the Nd 2O 3+miR-29a agomir group was lower than that in the Nd 2O 3+NC agomir group ( P<0.05) ; The relative expression level of TGF-β1 in the lung tissue of mice in the Nd 2O 3+miR-29a agomir group was lower than that in the Nd 2O 3+NC agomir group ( P<0.05) ; The expression level of Smad3 in the nucleus of the Nd 2O 3+miR-29a agomir group was lower than that of the Nd 2O 3+NC agomir group ( P<0.05). The prediction results of bioinformatics websites have found 152 downstream target genes related to miR-29a, among which FBN1, MAP2K6, KPNB1, COL1A2, SNIP1, LAMC1, and SP1 genes may be related to the regulatory effect of miR-29a on TGF-β1/Smad3 signaling pathway. Conclusion:miR-29a may affect lung fibrosis induced by rare earth Nd 2O 3 exposure in mice by regulating TGF-β1/Smad3 signaling pathway. Overexpression of miR-29a may inhibit TGF-β1/Smad3 signaling pathway and reduce the degree of pulmonary fibrosis in mice.
7.Exploration of detection methods for free silica with different crystal forms in dust
Qi GENG ; Chaoyang WANG ; Chengming MENG ; Zixin HE ; Liu YANG ; Yudan ZHANG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2024;42(3):180-183
Objective:To investigate the differences and applicability of free silica detection methods of different crystal forms in dust, and to provide a basis for the selection of various methods.Methods:From December 2021 to June 2022, dust samples from 20 enterprises in different industries in 18 cities in Henan Province were randomly selected as the investigation objects. X-ray diffraction (XRD) method was used to analyze the samples and classify the samples. Based on GBZ/T 192.4-2007 "Determination of Dust in the Air of Workplace-Part 4: Content of Free Silica in Dust", pyrophosphate method and infrared spectrophotometry were used for quantitative determination. The measured results were analyzed by paired sample t test to evaluate the advantages and disadvantages of the two methods and their applicable scope. Results:The XRD results of 20 dust samples could be divided into α, β, γ crystal types and the mixed type of α and γ. There was no significant difference between pyrophosphate method and infrared spectrophotometry ( P=0.180). The pyrophosphate method results of β, γ and α, γ mixed crystalline free silica were significantly higher than those of infrared spectrophotometry, and the difference was statistically significant ( P<0.001) . Conclusion:Pyrophosphate method and infrared spectrophotometry are suitable for α-type free silica, while pyrophosphate method is suitable for β, γ and α, γ mixed crystalline free silica.
8.Predictive value of preoperative frailty combined with nutritional status for prolonged postoperative ileus in patients with gynecologic malignancies
Beiying SHAN ; Yudan ZHOU ; Lixue WU ; Wenlan ZHU ; Jiwen WANG ; Meng ZHUANG ; Haijian SUN ; Jiru ZHANG
Chinese Journal of Anesthesiology 2024;44(4):406-411
Objective:To evaluate the predictive value of preoperative frailty combined with nutritional status for prolonged postoperative ileus (PPOI) in the patients with gynecological malignancies.Methods:Patients undergoing elective surgery for gynecological malignancies in the Affiliated Hospital of Jiangnan University from April 2022 to February 2023 were selected. The Frail scale was used to evaluate the frailty within 24 h of admission, and the nutritional status was evaluated by the Controlling Nutritional Status score. The general characteristics of patients and occurrence of PPOI were recorded, and the risk factors for PPOI were analyzed by multivariate logistic regression. The ability of frailty, nutritional status and their combination to predict PPOI was assessed by the receiver operating characteristic curve.Results:Two hundred and fourteen patients were finally included, 52 cases developed of PPOI, and 98 cases were frail patients. Preoperative frailty combined with moderate to severe malnutrition was an independent risk factor for PPOI in the patients with gynecological malignancies ( P<0.05), and the area under the curve in predicting the occurrence of PPOI was 0.796 (95% confidence interval 0.736-0.857) in the patients with gynecological malignancies. Conclusions:Preoperative frailty combined with moderate to severe malnutrition has a higher accuracy in predicting PPOI in the patients with gynecological malignancies.
9.Viral etiology and prognosis of severe acute respiratory tract infection in out-patient children under 5 years of age
Xue WANG ; Jun WEN ; Yufei SU ; Yudan ZHANG
Journal of Chinese Physician 2024;26(12):1798-1802
Objective:To investigate the etiology and prognosis of severe acute respiratory infection (SARI) in <5 year old outpatients.Methods:The data of 199 children with SARI admitted to the outpatient department of the Xi′an Children′s Hospital from January 2022 to December 2023 were included. Nasopharyngeal swabs were collected and the etiology of SARI virus in children was determined by polymerase chain reaction (PCR) within 48 h of study inclusion. The factors influencing respiratory support and length of stay in SARI children were analyzed by multiple linear regression.Results:Among the 199 patients included, 183 patients had positive nasopharyngeal swabs, with a positive rate of 92.0%. One pathogen was found in 124(62.3%) positive patients, two pathogens were found in 53(26.6%) positive patients, and three pathogens were found in 6(3.0%) positive patients. The most commonly detected viruses were rhinovirus (42.7%, 85/199), respiratory syncytial virus (33.2%, 66/199) and parainfluenza virus (14.1%, 28/199). Respiratory syncytial virus was detected in 40(54.8%) of the samples collected from infants aged 0 to 6 months, significantly higher than the frequency found in other age groups ( P<0.05). Adenoviruses were more common in the >12-24 month age group (22.0%). Age-specific weight Z score ( β=-0.223, 95% CI=-1.042--0.136, P=0.011) and SpO 2 ( β=-0.237, 95% CI=-0.21--0.037, P=0.006) were the influencing factors for respiratory support days in children with SARI. Age-specific weight Z score ( β=-0.223, 95% CI=-1.049--0.124, P=0.013) and SpO 2 ( β=-0.209, 95% CI=-0.204--0.020, P=0.017) were the factors influencing the length of hospital stay in SARI children. Conclusions:The findings of this study highlight the importance of viruses as SARI-associated pathogens in this population. Children at risk of a severe course of disease can be identified by measuring their age-specific weight Z score and SpO 2 on admission.
10.A highly sensitive bio-barcode immunoassay for multi-residue detection of organophosphate pesticides based on fluorescence anti-quenching
Xu LINGYUAN ; Zhang XIUYUAN ; El-Aty A.M.ABD ; Wang YUANSHANG ; Cao ZHEN ; Jia HUIYAN ; Salvador J.-PABLO ; Hacimuftuoglu AHMET ; Cui XUEYAN ; Zhang YUDAN ; Wang KUN ; She YONGXIN ; Jin FEN ; Zheng LUFEI ; Pujia BAIMA ; Wang JING ; Jin MAOJUN ; D.Hammock BRUCE
Journal of Pharmaceutical Analysis 2022;12(4):637-644
Balancing the risks and benefits of organophosphate pesticides(OPs)on human and environmental health relies partly on their accurate measurement.A highly sensitive fluorescence anti-quenching multi-residue bio-barcode immunoassay was developed to detect OPs(triazophos,parathion,and chlorpyrifos)in apples,turnips,cabbages,and rice.Gold nanoparticles were functionalized with monoclonal antibodies against the tested OPs.DNA oligonucleotides were complementarily hybridized with an RNA fluorescent label for signal amplification.The detection signals were generated by DNA-RNA hybridization and ribonuclease H dissociation of the fluorophore.The resulting fluorescence signal en-ables multiplexed quantification of triazophos,parathion,and chlorpyrifos residues over the concen-tration range of 0.01-25,0.01-50,and 0.1-50 ng/mL with limits of detection of 0.014,0.011,and 0.126 ng/mL,respectively.The mean recovery ranged between 80.3%and 110.8%with relative standard deviations of 7.3%-17.6%,which correlate well with results obtained by liquid chromatography-tandem mass spectrometry(LC-MS/MS).The proposed bio-barcode immunoassay is stable,reproducible and reliable,and is able to detect low residual levels of multi-residue OPs in agricultural products.

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