Extend the analytical power of your HORIBA fluorometer
HORIBA fluorometers are recognized worldwide for their high sensitivity and modular design, which allows them to adapt to a wide range of analytical applications. With the addition of our ABS-ACC absorption accessory, you can now effortlessly extend the performance and enhance the versatility of your instrument.
Measure absorption directly on your fluorometer
In many fluorescence experiments, knowledge of the sample's absorption properties is essential. The ABS-ACC absorption accessory fits directly into a cuvette sample holder, allowing you to measure the absorption spectrum or check the optical density of a liquid sample without reconfiguring your HORIBA fluorometer.
Complementary measures to fluorescence
Absorption measurements are essential for determining fluorescence quantum yield. By using the same optical path for fluorescence and absorption measurements, you obtain more accurate and consistent results. In addition, the ability to control optical density during a fluorescence experiment helps avoid internal filter effects (IFE) and improves the reliability of results. Comparing absorption and excitation spectra also provides valuable information about sample purity.
A practical, accurate, and economical tool
Simple and quick to use, ABS-ACC transforms your HORIBA fluorometer into a two-in-one instrument, eliminating the need for a separate, often more expensive UV-Vis spectrophotometer. It is particularly useful for monitoring sample concentration and determining whether absorbance is too high, thus ensuring linear and representative fluorescence.
Understanding the internal filter effect
The intensity of fluorescence is proportional to the light absorbed by the solution. However, this linear relationship is only valid for dilute solutions with an absorbance of less than approximately 0.1 DO. At higher concentrations, the incident light is partially absorbed before exciting the fluorophores, which artificially decreases the measured intensity: this is the internal filter effect (IFE). This phenomenon limits the linearity of the fluorescence signal at high concentrations, due to primary and secondary fluorescence reabsorption.
Compatibility of the ABS-ACC accessory
The ABS-ACC absorption accessory can be used with all sample holders on your instrument except multi-cell sample holders. However, when using a thermostatic sample holder, the sample temperature cannot be controlled during the absorption measurement because the sample will not be placed outside the thermostatic chamber.
