Small-volume Cell Research Articles

A dual-purpose absorbance-fluorescence detector for high-pressure liquid chromatography

A detector has been designed for high-speed liquid chromatography that simultaneously responds to sample absorbance and fluorescence in a single flow cell. Besides the advantages offered by different detection systems, the absorfance measurements provide a method for monitoring the fluorescence “inner filter” effect. The volume of the cell is small; the absorbance segment is 16 μl, and included in it is the 8-μl fluorescence segment. The minimum detectable concentration (signal-to-noise ratio = 2) of quinine in 0.1 N sulphuric acid is 0.3 ng/ml. The cell performs as well as an absorbance cell as other small-volume cells.

A new small-volume cell for studying infrared spectra of chemisorbed species

A cell with a small dead volume was constructed to study the spectra of adsorbed molecules as a function of surface concentration and temperature. A method is given for preparing large adsorbent discs.

A conductance-monitored diaphragm cell for diffusion measurements.

A diaphragm cell for diffusion measurements with concentrated electrolyte solutions is described in which conductances may be monitored during a diffusion experiment by means of a conductance cell attached to the outside of the top compartment. The conductance cell, which is of small volume and variable cell constant, is constructed so as to be closed when not in use but able to be reset precisely. Diffusion measurements made with potassium chloride and sodium chloride solutions have produced differential diffusion coefficients directly from a single experiment. The results are in excellent agreement with the literature.

Improved method for feeding and preparation of small-volume cell cultures.

Improved method for feeding and preparation of small-volume cell cultures.

Improved method for feeding and preparation of small-volume cell cultures.

Improved method for feeding and preparation of small-volume cell cultures.