Related Experiment Video
Updated: Feb 14, 2026
10:23
Time-Resolved Fluorescence Anisotropy from Single Molecules for Characterizing Local Flexibility in Biomolecules
Published on: April 25, 2025
1.1K
A space- and time-resolved single photon counting detector for fluorescence microscopy and spectroscopy.
X Michalet1, O H W Siegmund2, J V Vallerga2
1Department of Chemistry & Biochemistry, University of California at Los Angeles 607 Charles E. Young Drive E., Los Angeles, CA 90095, USA.
Proceedings of Spie--The International Society for Optical Engineering
|February 27, 2018
Summary
A new wide-field photon-counting detector (H33D) offers high-resolution imaging and fluorescence lifetime measurements. It shows promise for single-molecule imaging and high-throughput biomolecular interaction studies.
Area of Science:
- Optics and Photonics
- Biophysics
- Microscopy Instrumentation
Background:
- Advanced photon detection is crucial for high-resolution imaging and sensitive measurements in life sciences.
- Existing detectors like single-photon avalanche photodiodes (SPADs) and electron-multiplying cameras have limitations in throughput or resolution.
Purpose of the Study:
- To introduce and characterize a novel wide-field photon-counting detector, the H33D.
- To evaluate its performance for imaging and fluorescence lifetime measurements.
- To compare its capabilities against standard single-molecule detection methods.
Main Methods:
- Development of the H33D detector utilizing a multi-alkali photocathode, microchannel plate stack, and cross delay line anode.
- Installation of the H33D on a standard epifluorescence microscope.
- Performance comparison using model samples: fluorescent beads, quantum dots, and live cells.
Main Results:
- The H33D detector demonstrates high temporal and spatial resolutions with high throughput.
- Its imaging and fluorescence lifetime measurement capabilities were successfully evaluated.
- Performance was benchmarked against SPADs and electron-multiplying cameras.
Conclusions:
- The H33D detector is a promising advancement for single-molecule imaging and high-throughput biomolecular interaction studies.
- Future generations of H33D detectors are being designed for enhanced applications.
Related Concept Videos
01:17Space-Time Curvature and the General Theory of Relativity
4.6K
In 1905, Albert Einstein published his special theory of relativity. According to this theory, no matter in the universe can attain a speed greater than the speed of light in a vacuum, which thus serves as the speed limit of the universe.
This has been verified in many experiments. However, space and time are no longer absolute. Two observers moving relative to one another do not agree on the length of objects or the passage of time. The mechanics of objects based on Newton's laws of...
This has been verified in many experiments. However, space and time are no longer absolute. Two observers moving relative to one another do not agree on the length of objects or the passage of time. The mechanics of objects based on Newton's laws of...
4.6K
01:29Atomic Fluorescence Spectroscopy
985
Atomic fluorescence spectroscopy (AFS) is an analytical technique that involves the electronic transitions of atoms in a flame, furnace, or plasma being excited by electromagnetic (EM) radiation. When these atoms absorb energy, they become excited and subsequently release energy as they return to their original state. This emitted light, or "fluorescence," is observed at a right angle to the incident beam. Both absorption and emission processes transpire at distinct wavelengths, which...
985
01:16Confocal Fluorescence Microscopy
21.2K
Confocal microscopy is an advanced microscopic technique. The prime advantage of the confocal microscope over other microscopy techniques is its ability to block the out-of-focus light from the illuminated samples using pinholes. It is widely used with fluorescence optics to obtain high-resolution, sharp contrast images. Unlike optical microscopes, confocal microscopes use a focused beam of light laser to scan the entire sample surface at different z-planes. These microscopes are, therefore,...
21.2K
01:23Atomic Spectroscopy: Absorption, Emission, and Fluorescence
2.9K
Atomic spectroscopy is a vital tool in elemental analysis, both qualitatively and quantitatively. It can be broadly divided into optical spectroscopy, mass spectroscopy, and X-ray spectroscopy methods. The optical spectroscopic methods are atomic absorption spectroscopy (AAS), atomic emission spectroscopy (AES), and atomic fluorescence spectroscopy (AFS). The first step in all three methods is atomization, where the solid, liquid, or solution-phase samples are converted into gas-phase atoms and...
2.9K
01:21Gas Chromatography: Types of Detectors-I
1.7K
There are different types of detectors used in gas chromatography, each with its own specific properties that make it suitable for detecting certain types of analytes. The most commonly used detectors in GC are thermal conductivity detector (TCD), flame ionization detector (FID), and electron capture detector (ECD).
TCD is the earliest and most widely used detector that operates by measuring the changes in the thermal conductivity of the carrier gas. When a sample compound enters the detector,...
TCD is the earliest and most widely used detector that operates by measuring the changes in the thermal conductivity of the carrier gas. When a sample compound enters the detector,...
1.7K
01:37Super-resolution Fluorescence Microscopy
14.6K
Super-resolution fluorescence microscopy (SRFM) provides a better resolution than conventional fluorescence microscopy by reducing the point spread function (PSF). PSF is the light intensity distribution from a point that causes it to appear blurred. Due to PSF, each fluorescing point appears bigger than its actual size, and it is the PSF interference of nearby fluorophores that causes the blurred image. Various approaches to achieving higher resolution through SRFM have recently been...
14.6K