Leaflab 2 facilitates advanced studies of photosynthesis and respiration from solid-state samples. The system is ideally suited to busy research facilities where demands on equipment performance are high but is equally at home in teaching environments for under & post-grad plant biology studies of the photosynthetic processes.
Samples typically consist of leaf discs which are either cut from a broad leaf or made up of a “mat” of smaller leaves to form a circular disc of 10cm2. These samples are cut using a supplied leaf disc cutter. Changes in oxygen content of the sealed sample chamber are determined by the integral oxygen electrode mounted in the base of the chamber.
The system comprises the Oxylab electrode control unit, S1 Clark type electrode disc, LD2/3 advanced gas-phase electrode chamber, LH36/2R high intensity red LED light source, QSRED large are quantum sensor (red filtered for 550 – 750nm waveband) and Oxylab control and data acquisition software. All necessary accessories and spares are also included (excluding circulating water bath and Windows® PC).
OXYL1 – Oxylab Control Unit
The Oxylab oxygen electrode control unit operates in conjunction with the user-friendly O2view data acquisition and system control software to provide PC control of oxygen uptake or evolution measurements from the S1 Clark type oxygen electrode. Oxylab may be employed to function effectively across a broad range of applications from studies of mitochondrial and cellular respiration to measurements of isolated chloroplast suspensions or solid state leaf samples in photosynthesis research depending on the type of electrode chamber used.
Up to 2 individual Oxylab control units may be connected to a PC providing a convenient method of comparing signals from 2 channels simultaneously. Additionally, Oxylab may be configured to accept an optional auxiliary input signal (e.g. temperature, pH, chlorophyll fluorescence, TPP+ or other specific ion electrodes etc) using the appropriate accessory apparatus therefore extending the flexibility of the system.
Oxylab provides automation of complex light intensity changes during light response assays in conjunction with one of the compatible LED light sources available from Hansatech Instruments. Light tables (or photon flux density tables) are created within the O2view software via a user-friendly interface.
The Oxylab control unit connects to the serial port of a Windows® PC either directly or using a HAN/USB adapter (for newer PC’s with no serial ports). The control unit features a built-in magnetic stirrer (for liquid-phase measurements) and all the electronics required to control and measure the signal from the S1 oxygen electrode disc.
O2view Windows® software controls all major hardware and data acquisition functions including signal gain and back-off and simple calibration routines for both liquid and gas-phase measurements.
Data from the S1 electrode disc, optional auxiliary input signal and temperature signal from a QTP1 PAR/Temperature probe sensor are plotted as a chart recorder emulations in realtime with post-measurement data analysis tools included within the program. Completed experiments are saved in .CSV (Comma Separated Values) format which then may be opened directly in other Windows® data analysis applications such as Excel®.
The LD2/3 leaf-disc electrode chamber allows oxygen uptake / evolution measurements to be performed from leaf-discs, excised needles, algae, mosses, lichens etc with a surface area of up to 10cm2. A prepared S1 oxygen electrode disc is mounted directly below the sample chamber with the dome of the electrode forming the chamber floor. LD2/3 features an upper and lower water jacket ensuring superior temperature control of the sample and S1 electrode disc when linked to a temperature controlled circulating water bath. The leaf chamber section has 2 gas ports providing both a calibration and flow-through capability for rapid changes in the gaseous environment above the sample. An additional tapped and stoppered hole is provided for the introduction of an optional temperature sensor or similar auxiliary sensor.
A clear cast acrylic top window allows illumination of the sample via the LH36/2R LED light source with 1 additional optical port provided for either additional illumination or insertion of a quantum sensor, etc. A further port is orientated more vertically towards the sample and allows the fibre optic cable from the FMS 1 and FMS 2 modulated fluorimeters to be positioned close to the sample allowing simultaneous measurement of chlorophyll fluorescence.