The peroxyoxalate chemiluminescence(CL)detection of fatty acids in human se- rum combined with high-performance liquid chromatography (HPLC)is described.Some fatty acids in serum were extracted with a 1 :1(v/v)mixture...The peroxyoxalate chemiluminescence(CL)detection of fatty acids in human se- rum combined with high-performance liquid chromatography (HPLC)is described.Some fatty acids in serum were extracted with a 1 :1(v/v)mixture of chloroform-n-heptane.2-(4-Hydrazinocarbonyl- phenyl)-4,5-diphenylimidazole (HCPI) was used as a fluorescent labelling reagent of the fatty acids. The labelling reaction was carried out at 30℃ for 1 h at pH 6.5 and the resulting reaction mixture was sudjected to HPLC. The labelled fatty acid C_(17)(P-C_(17))was used as the internal standard. The la- belled fatty acids C_(16) and C_(18) were separated within 18 min on an ODS-8OTM column (150 mm× 6 mm ID,5μm,Tosoh Japan).The calibrlation curves of fatty acids from the spiked control serum were Y_1=-0.003 7 + 0.0028X_1,r=0.994 for FA C_( 16) and Y_2=0.00 1 2 + 0.00098X_2,r=0.999 for FA C_( 18),respectively.The average recoveries of facids from the spiked contrl serum were 107.2%(n=8,RSD=4.3%)for FA C_(16) and 97.35%(n=8, RSD=4.0%)for FA C_(18),respectively.The lower detection limits of fatty acids after reaction were 12μmol per 20μl injection for FA C_(16) and 18 μmol per 20μl injection for FA C_(18),respectively(signal to noise ratio, S/N=2).The HPLC/CL method was applied to the determination of FA C_(16) and FA C_(18) in normal human serum and the results showed that the concentrations of fatty acids in normal human serum were 0.134 ± 0.009 μ mol/ml serum(n=5) for FA C_(16) and 0.052±0.028 μmol/ml serum(n=5)for FA C_(18),respectively.展开更多
Coronavirus disease 2019(COVID-19),caused by SARS-CoV-2,has rapidly spread and caused a severe global pandemic.Because no specific drugs are available for COVID-19 and few vaccines are available for SARS-CoV-2,accurat...Coronavirus disease 2019(COVID-19),caused by SARS-CoV-2,has rapidly spread and caused a severe global pandemic.Because no specific drugs are available for COVID-19 and few vaccines are available for SARS-CoV-2,accurate and rapid diagnosis of COVID-19 has been the most crucial measure to control this pandemic.Here,we developed a portable bifunctional electrical detector based on graphene fieldeffect transistors for SARS-CoV-2 through either nucleic acid hybridization or antigen-antibody protein interaction,with ultra-low limits of detection of~0.1 and~1 fg mL^(−1) in phosphate buffer saline,respectively.We validated our method by assessment of RNA extracts from the oropharyngeal swabs of ten COVID-19 patients and eight healthy subjects,and the IgM/IgG antibodies from serum specimens of six COVID-19 patients and three healthy subjects.Here we show that the diagnostic results are in excellent agreement with the findings of polymerase chain reaction-based optical methods;they also exhibit rapid detection speed(~10 min for nucleic acid detection and~5 min for immunoassay).Therefore,our assay provides an efficient,accurate tool for high-throughput point-of-care testing.展开更多
文摘The peroxyoxalate chemiluminescence(CL)detection of fatty acids in human se- rum combined with high-performance liquid chromatography (HPLC)is described.Some fatty acids in serum were extracted with a 1 :1(v/v)mixture of chloroform-n-heptane.2-(4-Hydrazinocarbonyl- phenyl)-4,5-diphenylimidazole (HCPI) was used as a fluorescent labelling reagent of the fatty acids. The labelling reaction was carried out at 30℃ for 1 h at pH 6.5 and the resulting reaction mixture was sudjected to HPLC. The labelled fatty acid C_(17)(P-C_(17))was used as the internal standard. The la- belled fatty acids C_(16) and C_(18) were separated within 18 min on an ODS-8OTM column (150 mm× 6 mm ID,5μm,Tosoh Japan).The calibrlation curves of fatty acids from the spiked control serum were Y_1=-0.003 7 + 0.0028X_1,r=0.994 for FA C_( 16) and Y_2=0.00 1 2 + 0.00098X_2,r=0.999 for FA C_( 18),respectively.The average recoveries of facids from the spiked contrl serum were 107.2%(n=8,RSD=4.3%)for FA C_(16) and 97.35%(n=8, RSD=4.0%)for FA C_(18),respectively.The lower detection limits of fatty acids after reaction were 12μmol per 20μl injection for FA C_(16) and 18 μmol per 20μl injection for FA C_(18),respectively(signal to noise ratio, S/N=2).The HPLC/CL method was applied to the determination of FA C_(16) and FA C_(18) in normal human serum and the results showed that the concentrations of fatty acids in normal human serum were 0.134 ± 0.009 μ mol/ml serum(n=5) for FA C_(16) and 0.052±0.028 μmol/ml serum(n=5)for FA C_(18),respectively.
基金the National Key R&D Program of China(2017YFA0204901)the National Natural Science Foundation of China(21727806,21772003 and 21933001)+1 种基金the Tencent Foundation through the XPLORER PRIZE,Guangdong Major Project of Basic and Applied Basic Research(2019B030302007)Beijing National Laboratory for Molecular Sciences(BNLMS201901)。
文摘Coronavirus disease 2019(COVID-19),caused by SARS-CoV-2,has rapidly spread and caused a severe global pandemic.Because no specific drugs are available for COVID-19 and few vaccines are available for SARS-CoV-2,accurate and rapid diagnosis of COVID-19 has been the most crucial measure to control this pandemic.Here,we developed a portable bifunctional electrical detector based on graphene fieldeffect transistors for SARS-CoV-2 through either nucleic acid hybridization or antigen-antibody protein interaction,with ultra-low limits of detection of~0.1 and~1 fg mL^(−1) in phosphate buffer saline,respectively.We validated our method by assessment of RNA extracts from the oropharyngeal swabs of ten COVID-19 patients and eight healthy subjects,and the IgM/IgG antibodies from serum specimens of six COVID-19 patients and three healthy subjects.Here we show that the diagnostic results are in excellent agreement with the findings of polymerase chain reaction-based optical methods;they also exhibit rapid detection speed(~10 min for nucleic acid detection and~5 min for immunoassay).Therefore,our assay provides an efficient,accurate tool for high-throughput point-of-care testing.