Sulfonate groups were introduced to the surfaces of multiwalled carbon nanotubes by the radiation-induced graft polymerization of sodium 4-styrene sulfonate for the use as biosensor supports. Alcohol dehydrogenase was...Sulfonate groups were introduced to the surfaces of multiwalled carbon nanotubes by the radiation-induced graft polymerization of sodium 4-styrene sulfonate for the use as biosensor supports. Alcohol dehydrogenase was immobilized onto a sulfonated nanotube-supporting electrode with tris（2,2＇-bipyridyl） ruthenium（II） complex to form an electrogenerated chemilluminesce sensor of alcohol. When it was used to detect alcohol in cyclic voltammetric measurements, the sensor showed the linearity over the range of 1.0 × 10^-4 M-5.0 ×10^-2 M, with a correlation coefficient of 0.992 and a detection limit of 1.9 ×10^-6 M. In electrogenerated chemilluminesce detection, it showed linearity over 5.0 × 10^-4 M-1.0 × 10^-2 M, with a correlation coefficient of 0.986 and a detection limit of 1.0 × 10^-6 M. The sensor was demonstrated to be able to detect ethanol in commercial drinks.展开更多
One solid-state electrochemiluminescence （ECL） protein biosensor based on the competing reaction and substitute reaction between protein-to-DNA aptamer and DNA-to-DNA aptamer was proposed. Additionally, the biosenso...One solid-state electrochemiluminescence （ECL） protein biosensor based on the competing reaction and substitute reaction between protein-to-DNA aptamer and DNA-to-DNA aptamer was proposed. Additionally, the biosensor was based on ECL photo-quenching effect of ferrocene （Fc） to tris（2,2-bipyridyl）ruthenium（II） （Ru（bpy）2＋）. It was built up by modification of Au nanoparticles （AuNPs） and Ru（bpy）32＋ on one Au electrode firstly, and then self-assembly of one special double-stranded DNA （dsDNA） onto the electrode. This dsDNA was prepared by hybridization of one Fc labeled molecular beacon single-stranded DNA（ssDNA） and one anti-thrombin aptamer ssDNA. Without the target protein, this Fc-dsDNA/Ru（bpy）2＋- AuNPs/Au elec- trode trigged strong ECL signal, so we called it ECL ＂signal on＂ state. When thrombin was present in the sensing solution, the protein reacted with its aptamer from the Fc-dsDNA/Ru（bpy）3^2＋-AuNPs/Au electrode. Then the left molecular beacon ssDNA on the electrode recovered to its normal stem-loop structure and consequently its Fc labeler was close enough to the electrode surface to quench the ECL signal from Ru（bpy）3^2＋. It was in ECL ＂signal off＂ state. We measured the decrease in ECL intensity to sense the target protein. This was one endeavour to sense protein by using un-labeling target or probe strategy, which gave higher sensitivity and selectivity due to the better combination efficiency of protein and the un-labeled aptamer. 6.25 fmo/L thrombin was detected out,展开更多
目的探讨三联生物微阵列化学发光检测系统测定血清降钙素原(PCT)结果的可靠性。方法以罗氏Cobas e 601电化学发光检测系统为参照系统,三联生物微阵列化学发光检测系统为待评估系统,对血清PCT浓度进行测定并进行统计分析。结果罗氏电化...目的探讨三联生物微阵列化学发光检测系统测定血清降钙素原(PCT)结果的可靠性。方法以罗氏Cobas e 601电化学发光检测系统为参照系统,三联生物微阵列化学发光检测系统为待评估系统,对血清PCT浓度进行测定并进行统计分析。结果罗氏电化学发光检测系统血清PCT日内精密度的变异系数(CV)为5.33%～7.88%,日间CV为5.62%～8.56%。三联生物微阵列化学发光检测系统的日内CV为4.93%～7.28%,日间CV为5.47%～8.90%。两种检测系统有较好的相关性(回归方程y=1.174x+0.213,P<0.05),相关系数r^2为0.997。在医学决定水平(PCT为0.50 ng/ml和2.0 ng/ml)处的Kappa值分别为0.878(P=4.60×10^(-7))和0.933(P=7.72×10_(-8)),阳性符合率分别为94.44%和100.00%,阴性符合率分别为93.33%和95.45%。结论三联生物微阵列化学发光免疫分析法与罗氏电化学发光法测定血清PCT结果相关性和一致性好,可用于临床血清PCT的快速检测。展开更多
High-throughput pyrosequencing,carried out in millions of picoliter-sized reactors on a fiber-optic slide,is known for its longer read length.However,both optical crosstalk(which reduces the signal-to-noise ratio of C...High-throughput pyrosequencing,carried out in millions of picoliter-sized reactors on a fiber-optic slide,is known for its longer read length.However,both optical crosstalk(which reduces the signal-to-noise ratio of CCD images)and chemical retention adversely affect the accuracy of chemiluminescence determination,and ultimately decrease the read length and the accuracy of pyrosequencing results.In this study,both titanium and oxidized aluminum films were deposited on the side walls and upper faces of micro-reactor slides to enhance optical isolation;the films reduced the inter-well crosstalk by one order of magnitude.Subsequently,chemical retention was shown to be caused by the lower diffusion coefficient of the side walls of the picolitersized reactors because of surface roughness and random pores.Optically isolated fiber-optic slides over-coated with silicon oxide showed smoother surface morphology,resulting in little chemical retention;this was further confirmed with theoretical calculations.Picoliter-sized micro-reactors coated with titanium-silicon oxide films showed the least inter-well optical crosstalk and chemical retention;these properties are expected to greatly improve the high-throughput pyrosequencing performance.展开更多
文摘Sulfonate groups were introduced to the surfaces of multiwalled carbon nanotubes by the radiation-induced graft polymerization of sodium 4-styrene sulfonate for the use as biosensor supports. Alcohol dehydrogenase was immobilized onto a sulfonated nanotube-supporting electrode with tris（2,2＇-bipyridyl） ruthenium（II） complex to form an electrogenerated chemilluminesce sensor of alcohol. When it was used to detect alcohol in cyclic voltammetric measurements, the sensor showed the linearity over the range of 1.0 × 10^-4 M-5.0 ×10^-2 M, with a correlation coefficient of 0.992 and a detection limit of 1.9 ×10^-6 M. In electrogenerated chemilluminesce detection, it showed linearity over 5.0 × 10^-4 M-1.0 × 10^-2 M, with a correlation coefficient of 0.986 and a detection limit of 1.0 × 10^-6 M. The sensor was demonstrated to be able to detect ethanol in commercial drinks.
文摘One solid-state electrochemiluminescence （ECL） protein biosensor based on the competing reaction and substitute reaction between protein-to-DNA aptamer and DNA-to-DNA aptamer was proposed. Additionally, the biosensor was based on ECL photo-quenching effect of ferrocene （Fc） to tris（2,2-bipyridyl）ruthenium（II） （Ru（bpy）2＋）. It was built up by modification of Au nanoparticles （AuNPs） and Ru（bpy）32＋ on one Au electrode firstly, and then self-assembly of one special double-stranded DNA （dsDNA） onto the electrode. This dsDNA was prepared by hybridization of one Fc labeled molecular beacon single-stranded DNA（ssDNA） and one anti-thrombin aptamer ssDNA. Without the target protein, this Fc-dsDNA/Ru（bpy）2＋- AuNPs/Au elec- trode trigged strong ECL signal, so we called it ECL ＂signal on＂ state. When thrombin was present in the sensing solution, the protein reacted with its aptamer from the Fc-dsDNA/Ru（bpy）3^2＋-AuNPs/Au electrode. Then the left molecular beacon ssDNA on the electrode recovered to its normal stem-loop structure and consequently its Fc labeler was close enough to the electrode surface to quench the ECL signal from Ru（bpy）3^2＋. It was in ECL ＂signal off＂ state. We measured the decrease in ECL intensity to sense the target protein. This was one endeavour to sense protein by using un-labeling target or probe strategy, which gave higher sensitivity and selectivity due to the better combination efficiency of protein and the un-labeled aptamer. 6.25 fmo/L thrombin was detected out,
文摘目的探讨三联生物微阵列化学发光检测系统测定血清降钙素原(PCT)结果的可靠性。方法以罗氏Cobas e 601电化学发光检测系统为参照系统,三联生物微阵列化学发光检测系统为待评估系统,对血清PCT浓度进行测定并进行统计分析。结果罗氏电化学发光检测系统血清PCT日内精密度的变异系数(CV)为5.33%～7.88%,日间CV为5.62%～8.56%。三联生物微阵列化学发光检测系统的日内CV为4.93%～7.28%,日间CV为5.47%～8.90%。两种检测系统有较好的相关性(回归方程y=1.174x+0.213,P<0.05),相关系数r^2为0.997。在医学决定水平(PCT为0.50 ng/ml和2.0 ng/ml)处的Kappa值分别为0.878(P=4.60×10^(-7))和0.933(P=7.72×10_(-8)),阳性符合率分别为94.44%和100.00%,阴性符合率分别为93.33%和95.45%。结论三联生物微阵列化学发光免疫分析法与罗氏电化学发光法测定血清PCT结果相关性和一致性好,可用于临床血清PCT的快速检测。
基金supported by the Scientific Equipment Research Project of Chinese Academy of Sciences(YZ200823)
文摘High-throughput pyrosequencing,carried out in millions of picoliter-sized reactors on a fiber-optic slide,is known for its longer read length.However,both optical crosstalk(which reduces the signal-to-noise ratio of CCD images)and chemical retention adversely affect the accuracy of chemiluminescence determination,and ultimately decrease the read length and the accuracy of pyrosequencing results.In this study,both titanium and oxidized aluminum films were deposited on the side walls and upper faces of micro-reactor slides to enhance optical isolation;the films reduced the inter-well crosstalk by one order of magnitude.Subsequently,chemical retention was shown to be caused by the lower diffusion coefficient of the side walls of the picolitersized reactors because of surface roughness and random pores.Optically isolated fiber-optic slides over-coated with silicon oxide showed smoother surface morphology,resulting in little chemical retention;this was further confirmed with theoretical calculations.Picoliter-sized micro-reactors coated with titanium-silicon oxide films showed the least inter-well optical crosstalk and chemical retention;these properties are expected to greatly improve the high-throughput pyrosequencing performance.
