The Experts below are selected from a list of 447303 Experts worldwide ranked by ideXlab platform
Hadley D Sikes - One of the best experts on this subject based on the ideXlab platform.
-
balancing the initiation and molecular recognition capabilities of eosin macroinitiators of polymerization based signal amplification reactions
Macromolecular Rapid Communications, 2014Co-Authors: Hadley D SikesAbstract:: Coupling polymerization initiators to molecular recognition events provide the ability to amplify these events and detect them using the formation of a cross-linked polymer as an inexpensive readout that is visible to the unaided eye. The eosin-tertiary amine co-initiation system, activated by visible light, has proven utility in this context when an average of three eosin molecules are coupled to a protein Detection reagent. The present work addresses the question of how Detection Sensitivity is impacted when the number of eosin molecules per binding event increases in the range of two to fifteen. Unlike in other initiation systems, a non-monotonic relationship is observed between the number of initiators per binding event and the observed Detection Sensitivity.
-
impact of dissociation constant on the Detection Sensitivity of polymerization based signal amplification reactions
Analytical Chemistry, 2013Co-Authors: Kaja Kaastrup, Leslie Chan, Hadley D SikesAbstract:Many studies have demonstrated the concept of using free-radical polymerization reactions to provide signal amplification so that molecular recognition events indicative of disease states may be detected in a simple and low-cost manner. We provide the first systematic study of how the dissociation constant impacts Detection Sensitivity in these assays, having chosen a range of dissociation constants (nanomolar to picomolar) that is typical of those encountered in molecular diagnostic applications that detect protein–protein binding events. In addition, we use experimental results to validate a mass-action kinetic model that may be used to predict assay performance as an alternative or supplement to the empirical approach to developing new polymerization-based amplification assays that has characterized the field to date.
Ulf Landegren - One of the best experts on this subject based on the ideXlab platform.
-
western blotting via proximity ligation for high performance protein analysis
Molecular & Cellular Proteomics, 2011Co-Authors: Jijuan Gu, Asa Hagnermcwhirter, Poojahrau Sathiyanarayanan, Maria Hammond, Daniel Ivansson, Ola Söderberg, Mats Gullberg, Johan Johansson, Ulf LandegrenAbstract:Western blotting is a powerful and widely used method, but limitations in Detection Sensitivity and specificity, and dependence upon high quality antibodies to detect targeted proteins, are hurdles ...
-
western blotting via proximity ligation for high performance protein analysis
Molecular & Cellular Proteomics, 2011Co-Authors: Asa Hagnermcwhirter, Poojahrau Sathiyanarayanan, Maria Hammond, Daniel Ivansson, Ola Söderberg, Mats Gullberg, Johan Johansson, Yanling Liu, Ulf LandegrenAbstract:Western blotting is a powerful and widely used method, but limitations in Detection Sensitivity and specificity, and dependence upon high quality antibodies to detect targeted proteins, are hurdles to overcome. The in situ proximity ligation assay, based on dual antibody recognition and powerful localized signal amplification, offers increased Detection Sensitivity and specificity, along with an ability to identify complex targets such as phosphorylated or interacting proteins. Here we have applied the in situ proximity ligation assay mechanism in Western blotting. This combination allowed the use of isothermal rolling circle amplification of DNA molecules formed in target-specific ligation reaction, for 16-fold or greater increase in Detection Sensitivity. The increased specificity because of dual antibody recognition ensured highly selective assays, detecting the specific band when combinations of two cross-reactive antitubulin antibodies were used (i.e. both producing distinct nonspecific bands in traditional Western blotting). We also demonstrated Detection of phosphorylated platelet-derived growth factor receptor β by proximity ligation with one antibody directed against the receptor and another directed against the phosphorylated tyrosine residue. This avoided the need for stripping and re-probing the membrane or aligning two separate traditional blots. We demonstrate that the high-performance in situ proximity ligation-based Western blotting described herein is compatible with Detection via enhanced chemiluminescence and fluorescence Detection systems, and can thus be readily employed in any laboratory.
Yanling Liu - One of the best experts on this subject based on the ideXlab platform.
-
western blotting via proximity ligation for high performance protein analysis
Molecular & Cellular Proteomics, 2011Co-Authors: Asa Hagnermcwhirter, Poojahrau Sathiyanarayanan, Maria Hammond, Daniel Ivansson, Ola Söderberg, Mats Gullberg, Johan Johansson, Yanling Liu, Ulf LandegrenAbstract:Western blotting is a powerful and widely used method, but limitations in Detection Sensitivity and specificity, and dependence upon high quality antibodies to detect targeted proteins, are hurdles to overcome. The in situ proximity ligation assay, based on dual antibody recognition and powerful localized signal amplification, offers increased Detection Sensitivity and specificity, along with an ability to identify complex targets such as phosphorylated or interacting proteins. Here we have applied the in situ proximity ligation assay mechanism in Western blotting. This combination allowed the use of isothermal rolling circle amplification of DNA molecules formed in target-specific ligation reaction, for 16-fold or greater increase in Detection Sensitivity. The increased specificity because of dual antibody recognition ensured highly selective assays, detecting the specific band when combinations of two cross-reactive antitubulin antibodies were used (i.e. both producing distinct nonspecific bands in traditional Western blotting). We also demonstrated Detection of phosphorylated platelet-derived growth factor receptor β by proximity ligation with one antibody directed against the receptor and another directed against the phosphorylated tyrosine residue. This avoided the need for stripping and re-probing the membrane or aligning two separate traditional blots. We demonstrate that the high-performance in situ proximity ligation-based Western blotting described herein is compatible with Detection via enhanced chemiluminescence and fluorescence Detection systems, and can thus be readily employed in any laboratory.
Frank K Tittel - One of the best experts on this subject based on the ideXlab platform.
-
ppb level photoacoustic sensor system for saturation free co Detection of sf6 decomposition by use of a 10 w fiber amplified near infrared diode laser
Sensors and Actuators B-chemical, 2019Co-Authors: Lei Zhang, Xukun Yin, Lei Dong, Wangbao Yin, Liantuan Xiao, Suotang Jia, Frank K TittelAbstract:Abstract A photoacoustic sensor system for the ppb-level CO Detection of sulphur hexafluoride (SF6) decomposition was developed by use of a 10 W fiber-amplified near-infrared (NIR) diode laser. A photoacoustic Detection module with symmetrical construction was designed to allow a high power laser beam and a large gas flow. A theoretical model was developed to describe the dynamic equilibrium processes of CO molecular activation and deactivation in the presence of gas flow. The 10 W optical excitation power effectively compensates the CO weak absorption line strength in the NIR spectral region and realizes a saturation-free CO Detection with the assistance of the gas flow, resulting in a ppb-level CO Detection Sensitivity, which is comparable with the Detection Sensitivity obtained using a mid-infrared CO sensor.
-
ppb level Detection of acetylene based on qepas using a power amplified diode laser
Conference on Lasers and Electro-Optics, 2018Co-Authors: Yao Tong, Frank K TittelAbstract:An ultra-high sensitive C2H2-QEPAS sensor using an EDFA amplified diode laser was demonstrated. The 33.2 ppb Detection Sensitivity verified that the design of the reported QEPAS method demonstrated significantly enhanced sensor performance.
-
development of a mid infrared nitrogen dioxide sensor based on faraday rotation spectroscopy
Sensors and Actuators B-chemical, 2016Co-Authors: Rafal Lewicki, Kun Liu, Frank K TittelAbstract:Abstract A sensitive nitrogen dioxide (NO 2 ) sensor system based on Faraday Rotation Spectroscopy (FRS) was developed. The advantages of FRS include high Detection Sensitivity, zero background and free from the influence of diamagnetic species, such as humidity and carbon dioxide. A widely tunable external cavity quantum cascade laser (EC-QCL) was used as the excitation source. The tunable EC-QCL operates mode-hop free between 1600 cm −1 and 1650 cm −1 and allows targeting the optimum 4 41 40 Q-branch transition of NO 2 at 1613.2 cm −1 with an optical power of ∼135 mW. A custom made 22.47 cm long multipass gas cell (MPGC) was implemented in which the EC-QCL radiation was passed 45 times and provided an effective optical path length of 10.1 m in order to design a compact sensor system with high Detection Sensitivity. An air core solenoid surrounding the MPGC was used for generating a magnetic field of 200 G. Performance details of a FRS based sensor and its application for long time continuous NO 2 measurements are reported. The long time stability of the sensor system was evaluated. A NO 2 Detection Sensitivity based on an Allan deviation plot of ∼95 ppt was obtained by averaging the associated data for 300 s.
-
trace gas Detection based on off beam quartz enhanced photoacoustic spectroscopy optimization and performance evaluation
Review of Scientific Instruments, 2010Co-Authors: Kun Liu, Frank K Tittel, Lei Dong, Anatoliy A Kosterev, Weidong Chen, Lei Wang, Tu Tan, Weijun Zhang, Xiaoming GaoAbstract:A gas sensor based on off-beam quartz enhanced photoacoustic spectroscopy was developed and optimized. Specifically, the length and diameter of the microresonator tube were optimized, and the outer tube shape is modified for enhancing the trace gas Detection Sensitivity. The impact of the distance between the quartz tuning fork and an acoustic microresonator on the sensor performance was experimentally investigated. The sensor performance was evaluated by determining the Detection Sensitivity to H(2)O vapor in ambient air at normal atmospheric pressure. A normalized noise equivalent absorption coefficient (1σ) of 6.2×10(-9) cm(-1) W/Hz(1/2) was achieved.
Xiaoqin Qian - One of the best experts on this subject based on the ideXlab platform.
-
reflection mode optical resolution photoacoustic microscopy with high Detection Sensitivity by using a perforated acoustic mirror
Applied Physics Letters, 2018Co-Authors: Xiang Zhang, Qiuning Ding, Xiaoqin QianAbstract:Detection Sensitivity is one key factor determining the performance of an optical-resolution photoacoustic microscopy (OR-PAM) system. High Detection Sensitivity means a higher signal-to-noise ratio, cleaner images, and better biological safety. We demonstrate a reflection mode OR-PAM with high Detection Sensitivity by using a flat perforated acoustic mirror and a commercial focused ultrasound transducer. The proposed optical-acoustic combiner can provide optical-acoustic confocal alignment on the same side of the sample, low acoustic insert loss, and an undistorted optical path. Experimental measurements demonstrated its Detection Sensitivity and imaging quality. Finally, the real practical performance of this system was preliminarily examined by in vivo imaging of the capillaries in the ear of nude mice and the nevus on a volunteer's hand. Therefore, benefitting from the proposed design and the fine balance between Sensitivity, resolution, reflection mode, and ease of implementation, the proposed system might have valuable biomedical applications.Detection Sensitivity is one key factor determining the performance of an optical-resolution photoacoustic microscopy (OR-PAM) system. High Detection Sensitivity means a higher signal-to-noise ratio, cleaner images, and better biological safety. We demonstrate a reflection mode OR-PAM with high Detection Sensitivity by using a flat perforated acoustic mirror and a commercial focused ultrasound transducer. The proposed optical-acoustic combiner can provide optical-acoustic confocal alignment on the same side of the sample, low acoustic insert loss, and an undistorted optical path. Experimental measurements demonstrated its Detection Sensitivity and imaging quality. Finally, the real practical performance of this system was preliminarily examined by in vivo imaging of the capillaries in the ear of nude mice and the nevus on a volunteer's hand. Therefore, benefitting from the proposed design and the fine balance between Sensitivity, resolution, reflection mode, and ease of implementation, the proposed system...
-
reflection mode optical resolution photoacoustic microscopy with high Detection Sensitivity by using a perforated acoustic mirror
Applied Physics Letters, 2018Co-Authors: Xiang Zhang, Qiuning Ding, Xiaoqin Qian, Chao Tao, Xiaojun LiuAbstract:Detection Sensitivity is one key factor determining the performance of an optical-resolution photoacoustic microscopy (OR-PAM) system. High Detection Sensitivity means a higher signal-to-noise ratio, cleaner images, and better biological safety. We demonstrate a reflection mode OR-PAM with high Detection Sensitivity by using a flat perforated acoustic mirror and a commercial focused ultrasound transducer. The proposed optical-acoustic combiner can provide optical-acoustic confocal alignment on the same side of the sample, low acoustic insert loss, and an undistorted optical path. Experimental measurements demonstrated its Detection Sensitivity and imaging quality. Finally, the real practical performance of this system was preliminarily examined by in vivo imaging of the capillaries in the ear of nude mice and the nevus on a volunteer's hand. Therefore, benefitting from the proposed design and the fine balance between Sensitivity, resolution, reflection mode, and ease of implementation, the proposed system might have valuable biomedical applications.