Ultrasensitive nanomechanical instruments,e.g.atomic force microscopy(AFM),can be used to perform delicate biomechanical measurements and reveal the complex mechanical environment of biological processes.However,these...Ultrasensitive nanomechanical instruments,e.g.atomic force microscopy(AFM),can be used to perform delicate biomechanical measurements and reveal the complex mechanical environment of biological processes.However,these instruments are limited because of their size and complex feedback system.In this study,we demonstrate a miniature fiber optical nanomechanical probe(FONP)that can be used to detect the mechanical properties of single cells and in vivo tissue measurements.A FONP that can operate in air and in liquids was developed by programming a microcantilever probe on the end face of a single-mode fiber using femtosecond laser two-photon polymerization nanolithography.To realize stiffness matching of the FONP and sample,a strategy of customizing the microcantilever’s spring constant according to the sample was proposed based on structure-correlated mechanics.As a proof-of concept,three FONPs with spring constants varying from 0.421 N m^(−1)to 52.6 N m^(−1)by more than two orders of magnitude were prepared.The highest microforce sensitivity was 54.5 nmμN^(−1)and the detection limit was 2.1 nN.The Young’s modulus of heterogeneous soft materials,such as polydimethylsiloxane,muscle tissue of living mice,onion cells,and MCF-7 cells,were successfully measured,which validating the broad applicability of this method.Our strategy provides a universal protocol for directly programming fiber-optic AFMs.Moreover,this method has no special requirements for the size and shape of living biological samples,which is infeasible when using commercial AFMs.FONP has made substantial progress in realizing basic biological discoveries,which may create new biomedical applications that cannot be realized by current AFMs.展开更多
Optical fibers are typically used in telecommunications services for data transmission,where the use of fiber tags is essential to distinguish between the different transmission fibers or channels and thus ensure the ...Optical fibers are typically used in telecommunications services for data transmission,where the use of fiber tags is essential to distinguish between the different transmission fibers or channels and thus ensure the working functionality of the communication system.Traditional physical entity marking methods for fiber labeling are bulky,easily confused,and,most importantly,the label information can be accessed easily by all potential users.This work proposes an encrypted optical fiber tag based on an encoded fiber Bragg grating(FBG)array that is fabricated using a point-by-point femtosecond laser pulse chain inscription method.Gratings with different resonant wavelengths and reflectivities are realized by adjusting the grating period and the refractive index modulations.It is demonstrated that a binary data sequence carried by a fiber tag can be inscribed into the fiber core in the form of an FBG array,and the tag data can be encrypted through appropriate design of the spatial distributions of the FBGs with various reflection wavelengths and reflectivities.The proposed fiber tag technology can be used for applications in port identification,encrypted data storage,and transmission in fiber networks.展开更多
Micromanipulation and biological,material science,and medical applications often require to control or measure the forces asserted on small objects.Here,we demonstrate for the first time the microprinting of a novel f...Micromanipulation and biological,material science,and medical applications often require to control or measure the forces asserted on small objects.Here,we demonstrate for the first time the microprinting of a novel fiber-tip-polymer clamped-beam probe micro-force sensor for the examination of biological samples.The proposed sensor consists of two bases,a clamped beam,and a force-sensing probe,which were developed using a femtosecond-laser-induced two-photon polymerization(TPP)technique.Based on the finite element method(FEM),the static performance of the structure was simulated to provide the basis for the structural design.A miniature all-fiber micro-force sensor of this type exhibited an ultrahigh force sensitivity of 1.51 nmμN−1,a detection limit of 54.9 nN,and an unambiguous sensor measurement range of~2.9 mN.The Young’s modulus of polydimethylsiloxane,a butterfly feeler,and human hair were successfully measured with the proposed sensor.To the best of our knowledge,this fiber sensor has the smallest force-detection limit in direct contact mode reported to date,comparable to that of an atomic force microscope(AFM).This approach opens new avenues towards the realization of small-footprint AFMs that could be easily adapted for use in outside specialized laboratories.As such,we believe that this device will be beneficial for high-precision biomedical and material science examination,and the proposed fabrication method provides a new route for the next generation of research on complex fiber-integrated polymer devices.展开更多
Cantilevers in microelectromechanical systems have the advantages of non-labeling,real-time detection,positioning,and specificity.Rectangular solid,rectangular hollow,and triangular microcantilevers were fabricated on...Cantilevers in microelectromechanical systems have the advantages of non-labeling,real-time detection,positioning,and specificity.Rectangular solid,rectangular hollow,and triangular microcantilevers were fabricated on an optical fiber tip via two-photon polymerization.The mechanical properties were characterized using finite element simulations.Coating the microcantilever with a palladium film enabled high sensitivity and rapid hydrogen detection.The shape of the cantilever determines the sensitivity,whereas the thickness of the palladium film determines the response time.Additional microelectromechanical systems can be realized via polymerization combined with optical fibers.展开更多
Benefiting from the great advances of the femtosecond laser two-photon polymerization(TPP)technology,customized microcantilever probes can be accurately 3-dimensional(3D)manufactured at the nanoscale size and thus hav...Benefiting from the great advances of the femtosecond laser two-photon polymerization(TPP)technology,customized microcantilever probes can be accurately 3-dimensional(3D)manufactured at the nanoscale size and thus have exhibited considerable potentials in the fields of microforce,micro-vibration,and microforce sensors.In this work,a controllable microstructured cantilever probe on an optical fiber tip for microforce detection is demonstrated both theoretically and experimentally.The static performances of the probe are firstly investigated based on the finite element method(FEM),which provides the basis for the structural design.The proposed cantilever probe is then 3D printed by means of the TPP technology.The experimental results show that the elastic constant k of the proposed cantilever probe can be actively tuned from 2.46N/m to 62.35N/m.The force sensitivity is 2.5nm/μN,the Q-factor is 368.93,and the detection limit is 57.43nN.Moreover,the mechanical properties of the cantilever probe can be flexibly adjusted by the geometric configuration of the cantilever.Thus,it has an enormous potential for matching the mechanical properties of biological samples in the direct contact mode.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(62122057,62075136,62175165)Natural Science Foundation of Guangdong Province(2022B1515120061,2019B1515120042)Science and Technology Innovation Commission of Shenzhen(RCYX20200714114524139,JCYJ20200109114001806).
文摘Ultrasensitive nanomechanical instruments,e.g.atomic force microscopy(AFM),can be used to perform delicate biomechanical measurements and reveal the complex mechanical environment of biological processes.However,these instruments are limited because of their size and complex feedback system.In this study,we demonstrate a miniature fiber optical nanomechanical probe(FONP)that can be used to detect the mechanical properties of single cells and in vivo tissue measurements.A FONP that can operate in air and in liquids was developed by programming a microcantilever probe on the end face of a single-mode fiber using femtosecond laser two-photon polymerization nanolithography.To realize stiffness matching of the FONP and sample,a strategy of customizing the microcantilever’s spring constant according to the sample was proposed based on structure-correlated mechanics.As a proof-of concept,three FONPs with spring constants varying from 0.421 N m^(−1)to 52.6 N m^(−1)by more than two orders of magnitude were prepared.The highest microforce sensitivity was 54.5 nmμN^(−1)and the detection limit was 2.1 nN.The Young’s modulus of heterogeneous soft materials,such as polydimethylsiloxane,muscle tissue of living mice,onion cells,and MCF-7 cells,were successfully measured,which validating the broad applicability of this method.Our strategy provides a universal protocol for directly programming fiber-optic AFMs.Moreover,this method has no special requirements for the size and shape of living biological samples,which is infeasible when using commercial AFMs.FONP has made substantial progress in realizing basic biological discoveries,which may create new biomedical applications that cannot be realized by current AFMs.
基金supported by the National Natural Science Foundation of China(62122057,62075136,62105217,62205221,62205222)the Basic and Applied Basic Research Foundation of Guangdong Province(2022B1515120061)Shenzhen Science and Technology Program(Shenzhen Key Laboratory of Ultrafast Laser Micro/Nano Manufacturing ZDSYS20220606100405013,RCYX20200714114524139,JCYJ20200109114001806)。
文摘Optical fibers are typically used in telecommunications services for data transmission,where the use of fiber tags is essential to distinguish between the different transmission fibers or channels and thus ensure the working functionality of the communication system.Traditional physical entity marking methods for fiber labeling are bulky,easily confused,and,most importantly,the label information can be accessed easily by all potential users.This work proposes an encrypted optical fiber tag based on an encoded fiber Bragg grating(FBG)array that is fabricated using a point-by-point femtosecond laser pulse chain inscription method.Gratings with different resonant wavelengths and reflectivities are realized by adjusting the grating period and the refractive index modulations.It is demonstrated that a binary data sequence carried by a fiber tag can be inscribed into the fiber core in the form of an FBG array,and the tag data can be encrypted through appropriate design of the spatial distributions of the FBGs with various reflection wavelengths and reflectivities.The proposed fiber tag technology can be used for applications in port identification,encrypted data storage,and transmission in fiber networks.
基金This study was supported by the National Natural Science Foundation of China(NSFC)(62075136 and 62005173)Natural Science Foundation of Guangdong Province(2018B030306003 and 2020A0505100066)+1 种基金Science and Technology Innovation Commission of Shenzhen(JCYJ20200109114001806 and RCYX20200714114524139)China Postdoctoral Science Foundation(2020TQ0201).
文摘Micromanipulation and biological,material science,and medical applications often require to control or measure the forces asserted on small objects.Here,we demonstrate for the first time the microprinting of a novel fiber-tip-polymer clamped-beam probe micro-force sensor for the examination of biological samples.The proposed sensor consists of two bases,a clamped beam,and a force-sensing probe,which were developed using a femtosecond-laser-induced two-photon polymerization(TPP)technique.Based on the finite element method(FEM),the static performance of the structure was simulated to provide the basis for the structural design.A miniature all-fiber micro-force sensor of this type exhibited an ultrahigh force sensitivity of 1.51 nmμN−1,a detection limit of 54.9 nN,and an unambiguous sensor measurement range of~2.9 mN.The Young’s modulus of polydimethylsiloxane,a butterfly feeler,and human hair were successfully measured with the proposed sensor.To the best of our knowledge,this fiber sensor has the smallest force-detection limit in direct contact mode reported to date,comparable to that of an atomic force microscope(AFM).This approach opens new avenues towards the realization of small-footprint AFMs that could be easily adapted for use in outside specialized laboratories.As such,we believe that this device will be beneficial for high-precision biomedical and material science examination,and the proposed fabrication method provides a new route for the next generation of research on complex fiber-integrated polymer devices.
基金the National Natural Science Foundation of China(NSFC)(62122057,62075136)the Natural Science Foundation of Guangdong Province(2018B030306003,2020A0505100066)the Science and Technology Innovation Commission of Shenzhen(JCYJ20200109114001806,RCYX20200714114524139,JCYJ20180507184503128).
文摘Cantilevers in microelectromechanical systems have the advantages of non-labeling,real-time detection,positioning,and specificity.Rectangular solid,rectangular hollow,and triangular microcantilevers were fabricated on an optical fiber tip via two-photon polymerization.The mechanical properties were characterized using finite element simulations.Coating the microcantilever with a palladium film enabled high sensitivity and rapid hydrogen detection.The shape of the cantilever determines the sensitivity,whereas the thickness of the palladium film determines the response time.Additional microelectromechanical systems can be realized via polymerization combined with optical fibers.
基金supported by the Shenzhen Science and Technology Program (Grant No.RCYX20200714114524139)Shenzhen Key Laboratory of Ultrafast Laser Micro/Nano Manufacturing (Grant No.ZDSYS20220606100405013)+2 种基金Natural Science Foundation of GuangdongProvince (Grant Nos.2022B1515120061 and 2022A1515110971)National Natural Science Foundation of China (Grant Nos.62122057,62075136,62105217,and 62305223)China Postdoctoral Science Foundation (Grant No.2022M722173).
文摘Benefiting from the great advances of the femtosecond laser two-photon polymerization(TPP)technology,customized microcantilever probes can be accurately 3-dimensional(3D)manufactured at the nanoscale size and thus have exhibited considerable potentials in the fields of microforce,micro-vibration,and microforce sensors.In this work,a controllable microstructured cantilever probe on an optical fiber tip for microforce detection is demonstrated both theoretically and experimentally.The static performances of the probe are firstly investigated based on the finite element method(FEM),which provides the basis for the structural design.The proposed cantilever probe is then 3D printed by means of the TPP technology.The experimental results show that the elastic constant k of the proposed cantilever probe can be actively tuned from 2.46N/m to 62.35N/m.The force sensitivity is 2.5nm/μN,the Q-factor is 368.93,and the detection limit is 57.43nN.Moreover,the mechanical properties of the cantilever probe can be flexibly adjusted by the geometric configuration of the cantilever.Thus,it has an enormous potential for matching the mechanical properties of biological samples in the direct contact mode.
