Related Experiment Video
Updated: Jun 2, 2026

Phase Behavior of Charged Vesicles Under Symmetric and Asymmetric Solution Conditions Monitored with Fluorescence Microscopy
Published on: October 24, 2017
Visual semiquantification via the formation of phase segregation
Chun-Ting Kuo1, Yao-Min Liu, Sung-Hsun Wu
1Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan.
Abstract:
Colorimetry, one of the central themes in contemporary chemistry, generally relies on spectrometers to quantify specimens of interest. Developed herein is a rapid screening scheme to determine whether the amount of an analyte falls into a diagnostic concentration range by the naked eye. This is particularly important for applications under circumstances where instruments are not readily available. The aforementioned goal is demonstrated by utilizing copper-thiol chemistry as a model system in which polymerization occurs within a certain range of copper-to-cysteine mole ratios; hence, the targeted range of copper concentration is tunable by adjusting the amount of cysteine. Within and outside the range, the solutions appear cloudy and homogeneous, respectively. The reaction mechanism is proposed and scrutinized. The detection scheme is applied successfully on samples of human serum (15.7-23.6 μM) and pond water (<3.0 ppm or 47 μM) with a handy laser pointer.
Related Concept Videos
Phase Diagrams of Ternary Systems
The Phase Rule
Phase Diagrams
Phase Diagram
Phase Diagram
Phase Contrast and Differential Interference Contrast Microscopy
In-phase-contrast microscopes, interference between light directly passing through a cell and light refracted by cellular components is used to create high-contrast, high-resolution images without staining. It is the oldest and simplest type of microscope that creates an image by altering the wavelengths of light rays passing through the specimen. Altered wavelength paths are created using an annular stop in the condenser. The annular stop produces a hollow cone of...

