Colloidal gold immunochromatographic assay(CGIA)is commonly used for the on-site detection ofβ-agonists that are sometimes used illegally as feed additives in swine diets.However,few studies have evaluated the causes...Colloidal gold immunochromatographic assay(CGIA)is commonly used for the on-site detection ofβ-agonists that are sometimes used illegally as feed additives in swine diets.However,few studies have evaluated the causes of false-positive results that sometimes occur when applying CGIA in agricultural settings.In this study,we investigated if this false-positive phenomenon is related to the addition of certain traditional Chinese medicines(TCMs)to swine feed.We established and verified an extraction method for TCMs,and then applied CGIA to detectβ-agonists in the extracts of 105 TCMs and in the urine of swine dosed with TCMs,respectively.Liquid chromatography-tandem mass spectrometry was used to validate the results of the urine samples tested positive forβ-agonists using CGIA.The results were also verified using TCMs and colloidal gold test strips produced by different manufacturers.The extracts of Citri Reticulatae Pericarpium Viride,Citri Reticulatae Pericarpium,Magnoliae Officinalis Cortex,Chaenomelis Fructus,and Rhodiolae Crenulatae Radix Et Rhizoma were tested positive forβ-agonists.Meanwhile,the addition of Citri Reticulatae Pericarpium Viride and Citri Reticulatae Pericarpium to swine feed resulted in false-positive results forβ-agonists in swine urine.The results provide a new way to explain false-positive CGIA results and provide valuable information for livestock feeding programs.展开更多
Background:Schistosomiasis remains a major public health concern in China and an epidemiological survey has revealed that schistosome-infected bovines and goats are the main transmission sources for the disease.Theref...Background:Schistosomiasis remains a major public health concern in China and an epidemiological survey has revealed that schistosome-infected bovines and goats are the main transmission sources for the disease.Therefore,development of a sensitive technique for the diagnosis of schistosomiasis in domestic animals is necessary.Method:A novel colloidal gold immunochromatography assay(GICA)strip was developed for detecting Schistosoma japonicum in domestic animals.The colloidal gold was conjugated with recombinant streptococcal protein G(rSPG).As the test and control lines,the schistosome soluble egg antigen and rSPG,respectively,were blotted on nitrocellulose membrane.Results:The lowest detectable serum dilution was 1∶640 for schistosome-infected buffaloes.The cross-reaction rate of GICA was 14.29%with Paramphistomum sp.in buffaloes,16.67%with Haemonchus sp.in goats,and 33.33%with Orientobilharzia sp.in goats.These results were slightly lower and similar to those obtained through ELISA.Moreover,the strips for detecting S.japonicum in mice,rabbits,buffaloes,and goats showed high sensitivity(100.00%,100.00%,100.00%,and 100.00%,respectively)and specificity(100.00%,100.00%,94.23%,and 88.64%,respectively).And the sensitivity or specificity of the GICA strips did not present any significant differences after storage for 12 months at room temperature.When compared with ELISA,the GICA strips exhibited similar sensitivity and specificity in the diagnosis of schistosomiasis in mice,rabbits,buffaloes,and goats.Besides,only 5μl of serum are required for the test and the detection can be completed within 5 min.Conclusion:This study is the first to develop a GICA strip using gold-rSPG conjugate for the diagnosing of schistosomiasis in domestic animals,and preliminary results showed that the developed strip may be suitable for large-scale screening of schistosomiasis in endemic areas.展开更多
Synthetic contraceptive levonorgestrel （LNG） and glucocorticoid methylprednisolone （MP） residues are eventually discarded to environmental water system and function as environmental hormones, displaying potential ...Synthetic contraceptive levonorgestrel （LNG） and glucocorticoid methylprednisolone （MP） residues are eventually discarded to environmental water system and function as environmental hormones, displaying potential risk to humans and ecosystems, thus there is an urgent need for fast, sensitive and simultaneous detection of these compounds in water samples. In this study, a competitive immunochromatographic assay （ICA） using colloidal gold-labeled polyclonal antibodies as probes for rapid and simultaneous detection of LNG and MP in water samples was developed. The visual detection limits of LNG and MP in water samples were 10 ng/mL. The detection process could be completed within 10 min. There was no cross-reactivity of the ICA with other seven compounds. The strips could be stored at 4 ℃ for 10 weeks without significant loss of activity. The assay is a suitable tool for rapid and semi- quantitative detection of LNG and MP in water samples on site.展开更多
A simple, cheap and non-enzymatic colorimetric strategy for glucose detection has been designed based on the interactions between a phenylboronic acid （PBA） derivative, which is coupled with gold nanoparticles （Au...A simple, cheap and non-enzymatic colorimetric strategy for glucose detection has been designed based on the interactions between a phenylboronic acid （PBA） derivative, which is coupled with gold nanoparticles （AuNPs） as the colorimetric reporters, and glucose. The PBA-AuNPs hybrid system proposed here exhibits ordered photochemistry behaviors upon the addition of glucose at different pH values. There are two linear regions of glucose concentration for the glucose sensor at different pH values, i.e., between 0.1 mmol/L and 9.8 mmol/L at pH 6 with the detection limit of 64μmol/L and between 0 and 6.5 mmol/L with the detection limit of 48 μmol/L at pH 9, respectively. To test the practicality of the sensor system, we also applied this assay to detect a glucose sample in the artificial saliva.展开更多
基金the Guangdong Public Welfare Research and Capacity Building Project,China(2015A020209130)。
文摘Colloidal gold immunochromatographic assay(CGIA)is commonly used for the on-site detection ofβ-agonists that are sometimes used illegally as feed additives in swine diets.However,few studies have evaluated the causes of false-positive results that sometimes occur when applying CGIA in agricultural settings.In this study,we investigated if this false-positive phenomenon is related to the addition of certain traditional Chinese medicines(TCMs)to swine feed.We established and verified an extraction method for TCMs,and then applied CGIA to detectβ-agonists in the extracts of 105 TCMs and in the urine of swine dosed with TCMs,respectively.Liquid chromatography-tandem mass spectrometry was used to validate the results of the urine samples tested positive forβ-agonists using CGIA.The results were also verified using TCMs and colloidal gold test strips produced by different manufacturers.The extracts of Citri Reticulatae Pericarpium Viride,Citri Reticulatae Pericarpium,Magnoliae Officinalis Cortex,Chaenomelis Fructus,and Rhodiolae Crenulatae Radix Et Rhizoma were tested positive forβ-agonists.Meanwhile,the addition of Citri Reticulatae Pericarpium Viride and Citri Reticulatae Pericarpium to swine feed resulted in false-positive results forβ-agonists in swine urine.The results provide a new way to explain false-positive CGIA results and provide valuable information for livestock feeding programs.
基金This study was financially supported by the Basic Foundation for Scientific Research of State-level Public Welfare Institutes of China(Grant no.2014JB01).
文摘Background:Schistosomiasis remains a major public health concern in China and an epidemiological survey has revealed that schistosome-infected bovines and goats are the main transmission sources for the disease.Therefore,development of a sensitive technique for the diagnosis of schistosomiasis in domestic animals is necessary.Method:A novel colloidal gold immunochromatography assay(GICA)strip was developed for detecting Schistosoma japonicum in domestic animals.The colloidal gold was conjugated with recombinant streptococcal protein G(rSPG).As the test and control lines,the schistosome soluble egg antigen and rSPG,respectively,were blotted on nitrocellulose membrane.Results:The lowest detectable serum dilution was 1∶640 for schistosome-infected buffaloes.The cross-reaction rate of GICA was 14.29%with Paramphistomum sp.in buffaloes,16.67%with Haemonchus sp.in goats,and 33.33%with Orientobilharzia sp.in goats.These results were slightly lower and similar to those obtained through ELISA.Moreover,the strips for detecting S.japonicum in mice,rabbits,buffaloes,and goats showed high sensitivity(100.00%,100.00%,100.00%,and 100.00%,respectively)and specificity(100.00%,100.00%,94.23%,and 88.64%,respectively).And the sensitivity or specificity of the GICA strips did not present any significant differences after storage for 12 months at room temperature.When compared with ELISA,the GICA strips exhibited similar sensitivity and specificity in the diagnosis of schistosomiasis in mice,rabbits,buffaloes,and goats.Besides,only 5μl of serum are required for the test and the detection can be completed within 5 min.Conclusion:This study is the first to develop a GICA strip using gold-rSPG conjugate for the diagnosing of schistosomiasis in domestic animals,and preliminary results showed that the developed strip may be suitable for large-scale screening of schistosomiasis in endemic areas.
基金fnancial support from the National Natural Science Foundation of China(No.21175097)
文摘Synthetic contraceptive levonorgestrel （LNG） and glucocorticoid methylprednisolone （MP） residues are eventually discarded to environmental water system and function as environmental hormones, displaying potential risk to humans and ecosystems, thus there is an urgent need for fast, sensitive and simultaneous detection of these compounds in water samples. In this study, a competitive immunochromatographic assay （ICA） using colloidal gold-labeled polyclonal antibodies as probes for rapid and simultaneous detection of LNG and MP in water samples was developed. The visual detection limits of LNG and MP in water samples were 10 ng/mL. The detection process could be completed within 10 min. There was no cross-reactivity of the ICA with other seven compounds. The strips could be stored at 4 ℃ for 10 weeks without significant loss of activity. The assay is a suitable tool for rapid and semi- quantitative detection of LNG and MP in water samples on site.
基金supported by the National Natural Science Foundation of China for Young Scholars(No.21106064)the National Basic Research Program of China(No.2012CB725204)+1 种基金the National Science Foundation for Distinguished Young Scholars of China(No.21225626)the Natural Science Foundation of Jiangsu Province(Nos.BK2012822 and BK20131406)
文摘A simple, cheap and non-enzymatic colorimetric strategy for glucose detection has been designed based on the interactions between a phenylboronic acid （PBA） derivative, which is coupled with gold nanoparticles （AuNPs） as the colorimetric reporters, and glucose. The PBA-AuNPs hybrid system proposed here exhibits ordered photochemistry behaviors upon the addition of glucose at different pH values. There are two linear regions of glucose concentration for the glucose sensor at different pH values, i.e., between 0.1 mmol/L and 9.8 mmol/L at pH 6 with the detection limit of 64μmol/L and between 0 and 6.5 mmol/L with the detection limit of 48 μmol/L at pH 9, respectively. To test the practicality of the sensor system, we also applied this assay to detect a glucose sample in the artificial saliva.
