Molecular Devices SPECTRAmax 340PC, Operator'S Manual

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Chapter 1
1-14 SPECTRAmax 340PC Microplate Spectrophotometer Operator’s Manual
Wavelength Selection
In endpoint mode, you can select either single- or dual-wavelength mode during
stand-alone operation of the SPECTRAmax 340PC. Dual wavelength mode is
used when you wish data from both measurement and reference wavelengths to
be acquired. For kinetic readings, only single-wavelength mode is available.
Typically, you should select a measurement wavelength that is near the wave-
length of maximum absorption (
λ
max) for the chromophore/macromolecule of
interest. The reference wavelength (if any) is usually set to a wavelength at which
the chromophore/macromolecule shows relatively little absorption. The dual
wavelength feature increases endpoint accuracy—errors arising from optical
imperfections, such as scratches and plastic irregularities in the microplate, can be
effectively canceled out.
The display on the control panel shows the currently selected measurement
(
λ
1) and reference (
λ
2) wavelength (if any). You can change the wavelength(s)
by pressing the arrows on either wavelength selection key (
[\ 1 nm]
or
[\ 1-2 nm]
) until the display shows the desired wavelength. The wavelength list
will wrap around to the top when the last selectable wavelength is presented.
If the measurement and reference wavelengths are the same, the instru-
ment will beep and deselect dual wavelength.
Temperature Regulation
The SPECTRAmax 340PC has been designed to regulate the temperature of the
microplate chamber from 4°C above ambient to 45°C. Upon power up, when
the incubator is off, the temperature in the SPECTRAmax 340PC microplate
chamber is ambient and isothermal. Pressing the incubator
[On/Off]
key below
the
[Temp °C]
(incubator) key will cause the SPECTRAmax 340PC to begin
warming the microplate chamber. The temperature set point defaults to 37.0°C
at start-up. With the incubator on, the temperature of the microplate chamber
can be set and regulated from 4°C above ambient to 45°C.
Accuracy of the temperature set point is only guaranteed if the set point
is at least 4°C above ambient. If the temperature set point is lower than
the ambient temperature, the chamber temperature will remain at ambi-
ent. Temperature regulation is controlled by heaters only and, therefore,
cannot cool the temperature to a setting lower than ambient. Addition-
ally, the highest setting (45°C) can be achieved only if the ambient tem-
perature is >20°C.
You can change the temperature set point by pressing the up (
▲
) or the down
(
▼
) arrow on the
[Temp °C]
(incubator) key until the desired set point is shown
above the key in the display.
After activating the incubator, the microplate drawer will close (if open) after a
ten-second delay and the TEMPERATURE indicator located at the right of the
LCD will begin to flash and will continue flashing until the temperature within
the microplate chamber reaches the set point (± 0.3°C) when it will remain illu-
NOTE:
NOTE: