Turner Designs AquaFluor, Manual

Page: 14 / 23

Aqua Fluor
®
U
ser’s Manual
14
5 Applications
5.1 In Vivo Chlorophyll
In vivo chlorophyll analysis is the fluorescent detection of chlorophyll in live algal cells in
water. In this technique, the excitation light from the fluorometer passes through the
untreated sample of water and causes the chlorophyll
within the cells to fluoresce.
Environmental conditions, presence of interfering compounds, cellular physiology,
morphology, and light history can influence the relationship between the
in vivo fluorescence
and the actual concentration of chlorophyll in the sample. These factors cause in vivo
fluorescence to be a qualitative measure. Despite its qualitative nature, in vivo fluorescence
data can supply valuable information on the spatial and temporal distribution of chlorophyll
concentrations quickly and easily.
To obtain semi-quantitative data, the
in vivo fluorescence data must be correlated with
extracted chlorophyll data that can be obtained through the extraction and measurement of
the pigment from grab samples on a laboratory fluorometer, spectrophotometer or HPLC.
When collecting “grab” samples for chlorophyll extraction, the
in vivo reading must be noted
at the same time the sample is collected. Several samples should be collected within each
niche or environment.
Once the chlorophyll concentration has been determined through extraction, the
concentration should be correlated with the corresponding
in vivo value similar to what is
shown in Graph 1 below.
The
Aqua Fluor
®
calibration also requires a Blank sample and the best “true blank” is natural
water that has been filtered through a GF/F or membrane filter in order to remove the algal
cells but still retain any dissolved components. However, in most cases distilled water is
used for the Blank sample since the
in vivo readings are semi-quantitative at best.
Graph 1
For more details on chlorophyll analysis visit Turner Designs
’ website under Applications.