Valeport rapid ProSVT, Руководство по эксплуатации, Страница: 14 / 36

© 2019 Valeport Ltd
0660907a - rapidPro Operating Manual
Page 14
2.2.3. Linear Observation Range
The linear range is the concentration range for which the fluorometer signal is directly proportional to the
concentration of the fluorophore. The linear range starts at the minimum detection limit (MDL) and extends to the
upper limit of the instrument (dependent on fluorophore properties, optical filters, LED power, sample volume and
optical path length).
Hyperion Fluorometers have a calibrated linear response for 2 gain settings (e.g. the ranges 0-40 µg/l (G5) and 0-
800 µg/l (G1) for chlorophyll a). At higher concentrations, unlike analogue devices which generally flat-line at
full-scale deflection (e.g. FSD 5V) the Hyperion will continue to output a signal which increases with concentration
(i.e. meaningful data), though which is no longer guaranteed to be linear.
At very high fluorophore concentrations, signal quenching can occur, whereby the instrument output does not
increase linearly with fluorophore concentration (roll-off) and may decrease at even higher levels.
To perform a quick linearity check, dilute the sample 1:1 with RO water. If the reading decreases by 50%, the
sample is in the linear range. If the reading decreases by less than 50% or even increases, the sample is above
the linear range.