The first Respicond VIII was delivered 2013 to Zurich. Its new features include 2 separate 48 units water-baths, high quality temperature control resulting in less than +- =.005 degrees centigrade error. Program running in modern 64 bits computers with USB among the communication options.

Program screenshot

RESPICOND VIII measures the evolution of CO2 by capturing it in KOH. This results in a decrease of the conductance in the hydroxide solution, which is measured with platinum electrodes in each incubation vessel. It is a greatly improved version of the apparatus (Respicond I) described in: Nordgren, A. (1988) Soil Biology & Biochemistry 20, 955-958. RESPICOND VIII differs from VII by having separate highly insulated water-baths with 48 sample chambers each.  This gives the option of buying the Respicond VIII with only 48 incubation vessels and then at a later date add a second water-bath (See Price for details).

The Program

Data plot.

Data plot.

Versatile control software (a windows program) monitors each incubation vessel during the experiments.

Plotting and listing functions are accessible at all times during the experiments. You can plot the data as conductance (mS), mg accumulated CO2 and mg CO2 per hour, all three of which can be viewed in the listing window together with time. The latest scan for all the 96 vessels can also be listed in these three ways plus a number of parameters, that enable you to judge the developement of the experiments.

Thanks to modern electronics the precision is very high. Basal respiration rate can be measured for two months with the precision shown in the plot above, without replenishing the hydroxide, . For higher precision a more dilute hydroxide solution would be used, which however needs to be replenished more often.

Precision and frequency of measurements

High resolution plot.

High resolution plot.

You have a total of 96 (or 48) sample vessels available to you and you could measure 96 with good precision every 20 minutes. You can measure 4 samples every minute but those samples will have to respire sufficiently per minute to be interesting.

You can enter a general description of the experiment as well as the treatment of each vessel in the data file. The latter is shown when you plot the results. The data files can easily be converted to forms compatible with your statistics and spreadsheet programs.

Work on this equipment started 1980 and operational equipment has existed since 1983. Much experience has been gained during both hardware and software development, that now is built into the Respicond VIII respirometer.