MICROSCOPY-PAM Probing of Cells and Tissue in Microbial Mats and Leaves

► The MICROSCOPY-PAM is an extremely sensitive non-imaging chlorophyll fluorometer specialized to measure smallest spots in microscopic specimen like tissue preparations or suspensions.

► Essentially, the fluorometer consists of a modified epi-fluorescence microscope equipped with a modulated LED light source and a photomultiplier for detection of modulated chlorophyll fluorescence.

Universal Control Unit PAM-CONTROL

For control of Photomultiplier-detector PM-MF and LED

General Features

Data memory: 128 kB CMOS RAM providing memory for 4000 data sets

Microcontroller: CMOS 80C52

Display: 2 x 24 character alphanumerical LC-display with backlight

User interface: 2 x 4 touch-sensitive keys to operate the internal mode menu

Measured parameters: Fo, Fm, Fm', F, Fv/Fm (max. Yield), ΔF/Fm' (Yield), qP, qN, NPQ, PAR (using special micro quantum sensor), ETR (i.e. PAR x ΔF/Fm')

General Design

Power supply: Internal rechargeable battery 12 V/2 Ah, providing power for at least 10 000 Yield measurements, automatic power/off, battery charger MINI-PAM/L (100 to 240 V AC)

Dimensions: 17.6 cm x 11.5 cm x 9.5 cm (L x W x H)

Weight: 2 kg (incl. battery)

Operating temperature: -5 to +45 °C

Connectors

Actinic light: Drives up to three actinic LEDs

AUX input: Receives signals from temperature and light sensors

Aux output: Sends control signals for external LED drivers

Charge: Socket for battery charger

Far red light: Up to three far red LEDs can be driven

Measuring light: Capacity to drive up to three LEDs both as measuring and actinic light
sources, 12 LED intensity and 12 pulse frequency settings are available, automatic change
of measuring light frequency.

Output: Provides analog signal to chart recorder

Photomultiplier: Full control of photomultiplier PM-MF

RS232: Data transfer to computer using WinControl V. 2 software

Components of the MICROSCOPY-PAM

The MICROSCOPY-PAM system uses a Zeiss AxioScope.A1 epifluorescence microscope. The standard version of the microscope is equipped with a wide-aperture Zeiss Fluar objective lens with 20-fold magnification, and a blue 470 nm Zeiss LED module for fluorescence excitation. A red-orange 625 nm Zeiss LED module is available as alternative light source.

A special pulse modulation regime permits the use if the same LED module as source for measuring and actinic light as well as for saturation pulses.

Chlorophyll fluorescence is detected by a photomultiplier mounted on a special detector-ocular of the microscope. The ocular is equipped with an iris diaphragm with which the field of view can be narrowed down. A special dichroic beamsplitter filterset filters out the broadband fluorescence emission (λ>650 nm).

Fluorescence excitation and detection are controlled by the PAM-CONTROL unit, which allows stand-alone operation of the MICROSCOPY-PAM but also functions as an interface for operation of the system by a Windows computer.

The PAM-CONTROL unit can be operated by the WinControl software versions 2 or 3. The system includes, an RS 232 cable, a USB-RS 232 adapter (when an RS-232 port is not available), a charger MINI-PAM/L, a cable to connect a chart recorder, and a transport box.