Application note reviews the different ways that sensitivity figures for fluorescence spectrophotometers can be reported by manufacturers
An application note released by Lambda Advanced Technology reviews the different ways that sensitivity figures for fluorescence spectrophotometers can be reported by manufacturers. Confusion can arise as there is no internationally accepted standard method to specify the experimental conditions under which the measurements are made.
This makes it difficult to directly compare sensitivity figures from one instrument to another.
By changing the measurement conditions, the signal to noise ratio varies enormously, leading to gross differences in reported sensitivity figures.
Key factors are slit width and detector response time, and even the position at which noise is measured in the spectrum.
Varying slit width and detector response time can affect the sensitivity factors by more than two orders of magnitude, yet choosing conditions which give good sensitivity values can severely compromise the the actual performance of the instrument on real samples.
In addition, measuring noise in different ways can generate sensitivity figures varying by a factor of four from the same data.
The application note examines all of these factors in detail and shows clearly that bigger sensitivity figures do not automatically imply a better instrument.