Gallium nitride- （GaN） based high electron mobility transistors （HEMTs） provide a good platform for biological detection. In this work, both Au-gated AlInN/GaN HEMT and AlGaN/GaN HEMT biosensors are fabricated for...Gallium nitride- （GaN） based high electron mobility transistors （HEMTs） provide a good platform for biological detection. In this work, both Au-gated AlInN/GaN HEMT and AlGaN/GaN HEMT biosensors are fabricated for the detection of deoxyribonucleic acid （DNA） hybridization. The Au-gated AIInN/GaN HEMT biosensor exhibits higher sensitivity in comparison with the AlGaN/GaN HEMT biosensor. For the former, the drain-source current （VDS = 0.5 V） shows a clear decrease of 69μA upon the introduction of 1μmolL^-1 （μM） complimentary DNA to the probe DNA at the sensor area, while for the latter it is only 38 μA. This current reduction is a notable indication of the hybridization. The high sensitivity can be attributed to the thinner barrier of the AlInN/GaN heterostructure, which makes the two-dimensional electron gas channel more susceptible to a slight change of the surface charge.展开更多
Radioactive iodine gas detection has significant applications in the nuclear industry,particularly in nuclear accident scenarios and nuclear fuel reprocessing facilities.Herein,chemically stable metal-organic framewor...Radioactive iodine gas detection has significant applications in the nuclear industry,particularly in nuclear accident scenarios and nuclear fuel reprocessing facilities.Herein,chemically stable metal-organic frameworks(MOFs)with good affinity for iodine(including Zn(1,3-BDP),UiO-66,UiO-66-NH2,etc.)were computationally screened and drop-casted upon interdigitated electrodes(IDEs).These MOFs were used to develop advanced iodine sensors to achieve the direct electrical detection of I2 gas via impedance spectroscopy measurements.Upon exposure to I2 gas,a similar electrical response change has occurred for all the IDE sensors,despite in the different impedance ratio.In particular,UiO-66-coated sensors exhibited an impedance ratio>103 times,while the modification of amino groups(-NH2)enhanced the sensitivity,exceeding 104 times for UiO-66-NH2,and was accompanied by a better iodine uptake.Notably,the sensors fabricated from Zn(1,3-BDP),which also contained nitrogen atoms,exhibited excellent comprehensive sensing performance,including high sensitivity(with impedance ratio achieving 1.4×106 times),good recyclability,rapid response speed(with impedance change ratio of 250 times within 3 min),low detection limit(about 29 times under 300 ppm I2 vapor at 25°C),and high anti-interference ability.Our theoretical calculations revealed that the underlying I2 sensing mechanism could be attributed to a decreased band gap and enhanced electrical conductivity due to the new electronic states introduced by the adsorbed I2.This work proposes a novel and feasible method for investigating sensing materials and strategies to fabricate high-performance iodine gas sensors,providing a basis for developing nuclear radioactivity monitoring technology and emergency security safeguard equipment.展开更多
FoF1-ATPase is an active rotary motor,and generates three-ATP for each rotation.At saturated substrate concentration,the motor can achieve about 103 r.p.m,which means one motor can generate about 105 ATP molecules dur...FoF1-ATPase is an active rotary motor,and generates three-ATP for each rotation.At saturated substrate concentration,the motor can achieve about 103 r.p.m,which means one motor can generate about 105 ATP molecules during 30 min.Here,we constituted a novel nanodevice with a molecular rotary motor and a“battery”,FoF1-ATPase and chromatophore,and presented a novel method of sandwich type rotary biosensor based on εsubunit with one target-to-one motor,in which one target corresponds 105 ATP molecules as detection signals during 30 min.The target such as NT-proBNP detection demonstrated that this novel nanodevice has potential to be developed into an ultrasensitive biosensor to detect low expressed targets.展开更多
This study employs an N-carboxyanhydride ring-opening polymerization(NCA ROP)signal amplification strategy to construct a novel sensing system for the simple and rapid detection of tobacco mosaic virus RNA(tRNA).In th...This study employs an N-carboxyanhydride ring-opening polymerization(NCA ROP)signal amplification strategy to construct a novel sensing system for the simple and rapid detection of tobacco mosaic virus RNA(tRNA).In the developed fluorescent biosensor,carboxylated biomagnetic beads serve as carriers for target capture based on the complementary pairing of the aptamer bases.Subsequently,NCA ROP fluorescent peptides are utilized as highly biocompatible signal carriers to achieve sensitive detection of the target.Under the optimal conditions,the biosensor exhibits a broad linear detection range from 1 pM to 10 nM,with a detection limit as low as 0.085 pM.Furthermore,the fluorescent aptamer biosensor demonstrates robust affinity and reliability in recovery experiments involving healthy R ehmannia glutinosa leaf total RNA.This work establishes a robust platform for tRNA analysis,facilitating real-time and early diagnosis of various plant viruses.展开更多
A hollow-core metal-cladding waveguide（HCMW） optofluidic resonator that works based on a free-space coupling technique is designed. An HCMW can excite ultra-high-order modes（UOMs） at the coupled angle, which can b...A hollow-core metal-cladding waveguide（HCMW） optofluidic resonator that works based on a free-space coupling technique is designed. An HCMW can excite ultra-high-order modes（UOMs） at the coupled angle, which can be used as an optofluidic resonator to detect alterations of the epidermal growth factor receptor（EGFR）concentration. Theoretical analysis shows that the UOMs excited in the HCMW have a highly sensitive response to the refractive index（RI） variation of the guiding layer. An EGFR solution with a 0.2 ng/mL alteration is detected, and the RI variation caused by the concentration alteration is about 2.5 × 10^（-3）.展开更多
Low Earth Orbit(LEO)satellites,with their wide coverage and large number,have gradually become a crucial platform and means for navigation and positioning services.Compared to other LEO constellations,Starlink has ove...Low Earth Orbit(LEO)satellites,with their wide coverage and large number,have gradually become a crucial platform and means for navigation and positioning services.Compared to other LEO constellations,Starlink has over 6000 satellites in orbit,and its signals contain synchronous sequences usable for pseudo-range positioning.Thus,it has a potential serve as an alternative to Global Navigation Satellite System(GNSS)for providing Positioning,Navigation,and Timing(PNT)services.Compared to parabolic antennas and electronically scanned phased array antennas for receiving Starlink signals,wide-beam antennas(such as Low-Noise Block(LNB)downconverters)can be used to achieve low-cost multi-satellite tracking.However,it also encounters the issues of distinguishing between multiple satellite signals and low received signal power,which requires high-sensitivity detection.Moreover,there are some other issues such as unknown signal transmission time and real-time satellite orbits,thereby causing failure to navigation.Accordingly,this study focuses on LEO constellations represented by Starlink,proposes a joint pseudo-range and Doppler positioning method for Starlink satellite Signals of Opportunity(SOP)based on the comprehensive utilization of signals and information from LEO satellites.Moreover,this study analyzes the signal detection capability and satellite isolation method,examines the algorithm’s orbital error suppression performance,and establishes the concept of Equivalent Position Dilution of Precision(EPDOP)S_(EPDOP)for joint pseudo-range and Doppler positioning.In the experiment because Starlink satellite signals are not available in China,we take the advantage of Iridium NEXT satellites’global seamless coverage,utilize an algorithm to get pseudo-range observations with the Iridium NEXT signals,and then combine them with Starlink Doppler observations to achieve the joint pseudo-range and Doppler positioning of LEO satellites’SOPs.The experiment results demonstrate that when relying on Starlink Doppler observations for positioning,the proposed method achieves Two-Dimensional(2D)positioning accuracy of 3.6 m and Three-Dimensional(3D)positioning accuracy of 6.2 m.Compared to existing Starlink positioning algorithms based on parabolic antennas and electronically scanned phased array antennas,this method improves the accuracy by at least 35.7%.Additionally,Iridium NEXT signals are used to validate the performance of the proposed algorithm for joint pseudo-range and Doppler positioning.In a 40 km long-baseline scenario,the algorithm achieved a 2D positioning accuracy of 24 m and a 3D positioning accuracy of 41 m with Iridium NEXT satellite pseudo-range and Doppler measurements.展开更多
基金Supported by the National Key Research and Development Program of China under Grant Nos 2016YFB0400104 and2016YFB0400301the National Natural Sciences Foundation of China under Grant No 61334002the National Science and Technology Major Project
文摘Gallium nitride- （GaN） based high electron mobility transistors （HEMTs） provide a good platform for biological detection. In this work, both Au-gated AlInN/GaN HEMT and AlGaN/GaN HEMT biosensors are fabricated for the detection of deoxyribonucleic acid （DNA） hybridization. The Au-gated AIInN/GaN HEMT biosensor exhibits higher sensitivity in comparison with the AlGaN/GaN HEMT biosensor. For the former, the drain-source current （VDS = 0.5 V） shows a clear decrease of 69μA upon the introduction of 1μmolL^-1 （μM） complimentary DNA to the probe DNA at the sensor area, while for the latter it is only 38 μA. This current reduction is a notable indication of the hybridization. The high sensitivity can be attributed to the thinner barrier of the AlInN/GaN heterostructure, which makes the two-dimensional electron gas channel more susceptible to a slight change of the surface charge.
基金supported by the National Key R&D Program of China(No.2016YFC1402504).
文摘Radioactive iodine gas detection has significant applications in the nuclear industry,particularly in nuclear accident scenarios and nuclear fuel reprocessing facilities.Herein,chemically stable metal-organic frameworks(MOFs)with good affinity for iodine(including Zn(1,3-BDP),UiO-66,UiO-66-NH2,etc.)were computationally screened and drop-casted upon interdigitated electrodes(IDEs).These MOFs were used to develop advanced iodine sensors to achieve the direct electrical detection of I2 gas via impedance spectroscopy measurements.Upon exposure to I2 gas,a similar electrical response change has occurred for all the IDE sensors,despite in the different impedance ratio.In particular,UiO-66-coated sensors exhibited an impedance ratio>103 times,while the modification of amino groups(-NH2)enhanced the sensitivity,exceeding 104 times for UiO-66-NH2,and was accompanied by a better iodine uptake.Notably,the sensors fabricated from Zn(1,3-BDP),which also contained nitrogen atoms,exhibited excellent comprehensive sensing performance,including high sensitivity(with impedance ratio achieving 1.4×106 times),good recyclability,rapid response speed(with impedance change ratio of 250 times within 3 min),low detection limit(about 29 times under 300 ppm I2 vapor at 25°C),and high anti-interference ability.Our theoretical calculations revealed that the underlying I2 sensing mechanism could be attributed to a decreased band gap and enhanced electrical conductivity due to the new electronic states introduced by the adsorbed I2.This work proposes a novel and feasible method for investigating sensing materials and strategies to fabricate high-performance iodine gas sensors,providing a basis for developing nuclear radioactivity monitoring technology and emergency security safeguard equipment.
基金This work is supported by the National Basic Research Program of China(973 Program)under grant No.2013CB932804the National Natural Science Foundation of China under Grant No.11574329 and 11322543+2 种基金the Science and Technology Planning Project of General Administration of Quality Supervision,Inspection and Quarantine(AQSIQ)of PR China under Grant No.2015IK011AQSIQ industrial public service scientific research project of the Ministry of Science and Technology of P.R.China under Grant No.201410049The YS101 type high sensitive detector of chemiluminescence was manufactured by Yishang Innovation Technology Co.,Ltd.
文摘FoF1-ATPase is an active rotary motor,and generates three-ATP for each rotation.At saturated substrate concentration,the motor can achieve about 103 r.p.m,which means one motor can generate about 105 ATP molecules during 30 min.Here,we constituted a novel nanodevice with a molecular rotary motor and a“battery”,FoF1-ATPase and chromatophore,and presented a novel method of sandwich type rotary biosensor based on εsubunit with one target-to-one motor,in which one target corresponds 105 ATP molecules as detection signals during 30 min.The target such as NT-proBNP detection demonstrated that this novel nanodevice has potential to be developed into an ultrasensitive biosensor to detect low expressed targets.
基金supported by the Project of tacking of key scientifi c and technical problems in Henan Province(192102310033)。
文摘This study employs an N-carboxyanhydride ring-opening polymerization(NCA ROP)signal amplification strategy to construct a novel sensing system for the simple and rapid detection of tobacco mosaic virus RNA(tRNA).In the developed fluorescent biosensor,carboxylated biomagnetic beads serve as carriers for target capture based on the complementary pairing of the aptamer bases.Subsequently,NCA ROP fluorescent peptides are utilized as highly biocompatible signal carriers to achieve sensitive detection of the target.Under the optimal conditions,the biosensor exhibits a broad linear detection range from 1 pM to 10 nM,with a detection limit as low as 0.085 pM.Furthermore,the fluorescent aptamer biosensor demonstrates robust affinity and reliability in recovery experiments involving healthy R ehmannia glutinosa leaf total RNA.This work establishes a robust platform for tRNA analysis,facilitating real-time and early diagnosis of various plant viruses.
基金supported by the National Natural Science Foundation of China(No.61235009)the National Basic Research Programmer of China(No.2013CBA01703)
文摘A hollow-core metal-cladding waveguide（HCMW） optofluidic resonator that works based on a free-space coupling technique is designed. An HCMW can excite ultra-high-order modes（UOMs） at the coupled angle, which can be used as an optofluidic resonator to detect alterations of the epidermal growth factor receptor（EGFR）concentration. Theoretical analysis shows that the UOMs excited in the HCMW have a highly sensitive response to the refractive index（RI） variation of the guiding layer. An EGFR solution with a 0.2 ng/mL alteration is detected, and the RI variation caused by the concentration alteration is about 2.5 × 10^（-3）.
基金support is received from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA0350101)the Project(E2M4140306).
文摘Low Earth Orbit(LEO)satellites,with their wide coverage and large number,have gradually become a crucial platform and means for navigation and positioning services.Compared to other LEO constellations,Starlink has over 6000 satellites in orbit,and its signals contain synchronous sequences usable for pseudo-range positioning.Thus,it has a potential serve as an alternative to Global Navigation Satellite System(GNSS)for providing Positioning,Navigation,and Timing(PNT)services.Compared to parabolic antennas and electronically scanned phased array antennas for receiving Starlink signals,wide-beam antennas(such as Low-Noise Block(LNB)downconverters)can be used to achieve low-cost multi-satellite tracking.However,it also encounters the issues of distinguishing between multiple satellite signals and low received signal power,which requires high-sensitivity detection.Moreover,there are some other issues such as unknown signal transmission time and real-time satellite orbits,thereby causing failure to navigation.Accordingly,this study focuses on LEO constellations represented by Starlink,proposes a joint pseudo-range and Doppler positioning method for Starlink satellite Signals of Opportunity(SOP)based on the comprehensive utilization of signals and information from LEO satellites.Moreover,this study analyzes the signal detection capability and satellite isolation method,examines the algorithm’s orbital error suppression performance,and establishes the concept of Equivalent Position Dilution of Precision(EPDOP)S_(EPDOP)for joint pseudo-range and Doppler positioning.In the experiment because Starlink satellite signals are not available in China,we take the advantage of Iridium NEXT satellites’global seamless coverage,utilize an algorithm to get pseudo-range observations with the Iridium NEXT signals,and then combine them with Starlink Doppler observations to achieve the joint pseudo-range and Doppler positioning of LEO satellites’SOPs.The experiment results demonstrate that when relying on Starlink Doppler observations for positioning,the proposed method achieves Two-Dimensional(2D)positioning accuracy of 3.6 m and Three-Dimensional(3D)positioning accuracy of 6.2 m.Compared to existing Starlink positioning algorithms based on parabolic antennas and electronically scanned phased array antennas,this method improves the accuracy by at least 35.7%.Additionally,Iridium NEXT signals are used to validate the performance of the proposed algorithm for joint pseudo-range and Doppler positioning.In a 40 km long-baseline scenario,the algorithm achieved a 2D positioning accuracy of 24 m and a 3D positioning accuracy of 41 m with Iridium NEXT satellite pseudo-range and Doppler measurements.
