Capacitance Measurements
Capacitance Measurements - Related Videos
08:56
Capacitance
0 Views •
2023
Source: Yong P. Chen, PhD, Department of Physics & Astronomy, College of Science, Purdue University, West Lafayette, IN This experiment will use commercial capacitors and a parallel plate capacitor to demonstrate the concept of capacitance. A capacitor stores opposite charges on two conductors, for example two opposite metal plates, leading to a potential difference (voltage drop) between the two conductors. The amount of charge on each conductor is proportional to this voltage drop, with...
05:15
Target Peptide Detection and Measurement Using a Capacitive Immunoprobe Biosensor
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2025
This video demonstrates a method for detecting and quantifying peptide transmitters using a capacitive immunoprobe biosensor. The functionalized electrode, coated with antibodies, interacts with peptides of interest, leading to a signal change that allows precise measurement and detection of peptides.
09:16
Patch-clamp Capacitance Measurements and Ca2+ Imaging at Single Nerve Terminals in Retinal Slices
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Cited by 12 •
2012
Here we describe a protocol for the preparation of agar-embedded retinal slices that are suitable for electrophysiology and Ca2+ imaging. This method allows one to study ribbon-type synapses in retinal microcircuits using direct patch-clamp recordings of single presynaptic nerve terminals.
10:53
Scanning-probe Single-electron Capacitance Spectroscopy
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2013
Scanning-probe single-electron capacitance spectroscopy facilitates the study of single-electron motion in localized subsurface regions. A sensitive charge-detection circuit is incorporated into a cryogenic scanning probe microscope to investigate small systems of dopant atoms beneath the surface of semiconductor samples.
14:58
Methods for Patch Clamp Capacitance Recordings from the Calyx
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Cited by 6 •
2007
We demonstrate the basic techniques for presynaptic patch clamp recording at the calyx of Held, a mammalian central nervous system nerve terminal.
FAQs
A voltage change across the lipid bilayer produces a charging current as the membrane stores electrical charge. Measuring the current response to that voltage change allows capacitance to be calculated. In electrophysiology, this electrical relationship provides a way to follow membrane behavior without directly labeling or imaging the membrane, making it useful for observing rapid cellular events.
Membrane capacitance is related to the amount of membrane surface area. When the membrane expands or contracts, the measured capacitance can change accordingly. An increase may reflect membrane growth or vesicle fusion, whereas a decrease may indicate membrane retrieval. These interpretations connect an electrical measurement to physical remodeling of the cell surface.
Capacitance measurements focus on the charging response of the membrane when its voltage changes, while patch-clamp recordings can also monitor currents associated with ion-channel activity. The same electrophysiological setup can therefore provide complementary information: capacitance reports membrane-area dynamics, and channel-related signals describe electrical activity linked to ion movement.
The charging-current response can be followed during brief changes in membrane state, allowing capacitance measurements to detect fast membrane dynamics. This sensitivity is important when events occur on short timescales, such as vesicle fusion or retrieval. Because the readout is electrical and noninvasive, it can track these changes in living, electrically active cells.
A typical workflow integrates capacitance measurement with a patch-clamp recording. The experiment applies a voltage change across the cell membrane, records the resulting charging current, and uses that current response to calculate capacitance. Researchers then examine changes in the measured value over time and relate them to membrane growth, fusion, retrieval, or other cellular activity.
A change in capacitance can indicate that the cell’s membrane surface area has changed. In the biological context, increases may be associated with membrane growth or vesicle fusion, while decreases may reflect membrane retrieval. Interpreting the direction and timing of the change helps connect the electrical record with the underlying dynamics of the cell surface.
These measurements are used to monitor exocytosis, endocytosis, ion-channel activity, and cellular secretion. They are particularly relevant to neurons, endocrine cells, and other electrically active cells, where membrane trafficking and electrical signals occur together. In these settings, capacitance recordings help relate membrane-area changes to secretion and communication-related cellular processes.