Capacitive Sensor to Monitor Enzyme Activity by Following Degradation of Macromolecules in Real Time

Due to the flexible and compact structures, spherical joints are widely used in parallel manipulators and industrial robots. Real-time detection of the clearance between the ball and the socket in spherical joints is beneficial to compensate motion errors of mechanical systems and improve their transmission accuracy. This work proposes an improved capacitive sensor for detecting the micro-clearance of spherical joints. First, the structure of the capacitive sensor is proposed. Then, the mathematical model for the differential capacitance of the sensor and the eccentric micro-displacement of the ball is deduced. Finally, the capacitance values of the capacitive sensor are simulated with Ansoft Maxwell. The simulated values of the differential capacitances at different eccentric displacements agree well with the theoretical ones, indicating the feasibility of the proposed detection method. In addition, the simulated results show that the proposed capacitive sensor could effectively reduce the capacitive fringe effect, improving the measurement accuracy.

Download Full-text

Quantitative real time PCR of deoxycytidine kinase mRNA by Light Cycler PCR in relation to enzyme activity and gemcitabine sensitivity

Cancer Letters ◽

10.1016/j.canlet.2004.04.016 ◽

2004 ◽

Vol 213 (2) ◽

pp. 173-179 ◽

Cited By ~ 15

Author(s):

Jennifer Sigmond ◽

Judith R. Kroep ◽

Willem Loves ◽

Giovanni Codacci-Pisanelli ◽

Godefridus J. Peters

Keyword(s):

Enzyme Activity ◽

Real Time ◽

Real Time Pcr ◽

Deoxycytidine Kinase ◽

Quantitative Real Time Pcr ◽

Light Cycler

Download Full-text

The inner mechanics of Rhodopsin Guanylyl Cyclase during 2cGMP-formation revealed by real-time FTIR spectroscopy

eLife ◽

10.7554/elife.71384 ◽

2021 ◽

Vol 10 ◽

Author(s):

Paul Fischer ◽

Shatanik Mukherjee ◽

Enrico Peter ◽

Matthias Broser ◽

Franz Bartl ◽

...

Keyword(s):

Enzyme Activity ◽

Real Time ◽

Protein Interactions ◽

Uv Light ◽

Spectroscopic Characterization ◽

Binding Pocket ◽

Molecular Signaling ◽

Protein Protein Interactions ◽

Regulatory Influence ◽

Truncated Variants

Enzymerhodopsins represent a recently discovered class of rhodopsins which includes histidine kinase rhodopsin, rhodopsin phosphodiesterases and rhodopsin guanylyl cyclases (RGCs). The regulatory influence of the rhodopsin domain on the enzyme activity is only partially understood and holds the key for a deeper understanding of intra-molecular signaling pathways. Here we present a UV-Vis and FTIR study about the light-induced dynamics of a RGC from the fungus Catenaria anguillulae, which provides insights into the catalytic process. After the spectroscopic characterization of the late rhodopsin photoproducts, we analyzed truncated variants and revealed the involvement of the cytosolic N-terminus in the structural rearrangements upon photo-activation of the protein. We tracked the catalytic reaction of RGC and the free GC domain independently by UV-light induced release of GTP from the photolabile NPE-GTP substrate. Our results show substrate binding to the dark-adapted RGC and GC alike and reveal differences between the constructs attributable to the regulatory influence of the rhodopsin on the conformation of the binding pocket. By monitoring the phosphate rearrangement during cGMP and pyrophosphate formation in light-activated RGC, we were able to confirm the M state as the active state of the protein. The described setup and experimental design enable real-time monitoring of substrate turnover in light-activated enzymes on a molecular scale, thus opening the pathway to a deeper understanding of enzyme activity and protein-protein interactions.

Download Full-text

Low-cost capacitive sensor for detecting palm-wood moisture content in real-time

Heliyon ◽

10.1016/j.heliyon.2020.e04555 ◽

2020 ◽

Vol 6 (8) ◽

pp. e04555 ◽

Cited By ~ 1

Author(s):

Suratsavadee K. Korkua ◽

Siraporn Sakphrom

Keyword(s):

Moisture Content ◽

Real Time ◽

Low Cost ◽

Capacitive Sensor ◽

Wood Moisture Content ◽

Wood Moisture

Download Full-text

A Novel Application of the Cross-Capacitive Sensor in Real-Time Condition Monitoring of Transformer Oil

IEEE Transactions on Instrumentation and Measurement ◽

10.1109/tim.2021.3111979 ◽

2021 ◽

Vol 70 ◽

pp. 1-12

Author(s):

Obaidur Rahman ◽

Tarikul Islam ◽

Neeraj Khera ◽

Shakeb A. Khan

Keyword(s):

Real Time ◽

Condition Monitoring ◽

Capacitive Sensor ◽

Transformer Oil ◽

Time Condition ◽

The Cross

Download Full-text

A Novel Approach for Detecting Rotational Angles of a Precision Spherical Joint Based on a Capacitive Sensor

Micromachines ◽

10.3390/mi10050280 ◽

2019 ◽

Vol 10 (5) ◽

pp. 280 ◽

Cited By ~ 4

Author(s):

Wen Wang ◽

He Yang ◽

Min Zhang ◽

Zhanfeng Chen ◽

Guang Shi ◽

...

Keyword(s):

Real Time ◽

Capacitive Sensor ◽

Parallel Manipulators ◽

Angle Measurement ◽

Mechanical Transmission ◽

Spherical Joint ◽

Rotational Angle ◽

Loop Control ◽

Novel Approach ◽

The Mathematical Model

Precision spherical joints are commonly employed as multiple degree-of-freedom (DOF) mechanical hinges in many engineering applications, e.g., robots and parallel manipulators. Real-time and precise measurement of the rotational angles of spherical joints is not only beneficial to the real-time and closed-loop control of mechanical transmission systems, but also is of great significance in the prediction and compensation of their motion errors. This work presents a novel approach for rotational angle measurement of spherical joints with a capacitive sensor. First, the 3-DOF angular motions of a spherical joint were analyzed. Then, the structure of the proposed capacitive sensor was presented, and the mathematical model for the rotational angles of a spherical joint and the capacitance of the capacitors was deduced. Finally, the capacitance values of the capacitors at different rotations were simulated using Ansoft Maxwell software. The simulation results show that the variation in the simulated capacitance values of the capacitors is similar to that of the theoretical values, suggesting the feasibility and effectiveness of the proposed capacitive detection method for rotational angles of spherical joints.

Download Full-text