The methodical principle of an automated selection system for antibiotic producers, the Autoselectsystem, consisting of six machines and a computer is explained. In order to work with this machines the following material is needed: Cassettes with 64 microculture cups for cultivation of colonies on agar, cassettes with glass‐tubes for dilution of samples, and test‐plates with 64 holes for performing the agar diffusion test. The cups, the tubes and holes are arranged in a pattern of 8×8. In a serie of papers the machines will be described.
As a part of the Autoselect-system an eightfold diluter is described. Cassettes with 64 tubes are placed on the carriage of the machine and moved automatically in eight steps. One of the cassettes is loaded with separated samples in 64 tubes and the other one with 64 empty tubes. When the carriage stops, a defined volume of samples is exhausted by eight pipettes, mounted on a bridge spanning over the ground unit from left to right, and after beeing moved to the second cassette the pipettes deliver the samples into a row of empty tubes. At the same time by eight syringes mounted on both sides of the machine a defined volume of buffer is delivered through tubes and canules. By this way all samples can be diluted in two minutes.
ZnsammenfassungEin Achtfach-Verdunnungsautomat a1s Teil des Autoselect-Systems wird beschrieben. Auf einem Transportwagen wird eine Kassette mit 64 Proben und eine weitere mit 64 leeren Rohrchen in 8 Arbeitsschritten bewegt. Der Verdiinnungsvorgang 18;uft folgendermaBen ab : -Entnahme eines definierten Volumens der Antibiotika-Kulturlosungen aus einer Reihe von Proben mittels 8 Pipetten, die von einem Pipettenwagen Lhnlich einer Briicke quer iiber die Grundeinheit angeordnet sind. -Nach Transport des Pipettenwagens wird die Fliissigkeit in leere Rohrchen der anderen Kassette entleert; gleichzeitig wird aus 8 Spritzen, die seitlich angeordnet sind, eine definierte Menge Puffer zur Verdiinnung in die R6hrchen dosiert. -I n angegebener Weise werden alle 64 Proben innerhalb von 2 Minuten verdiinnt.
An eightfold punch belonging to the Aùtoselect‐system is described. It is provided for the preparation of bioassay plates. From the agar of large quadratic test plates moving automatically on a carriage of the machine, 64 holes are made by eight punches. The punches arranged in a row over the test plate are lowered, if the carriage stops, and so they cut out and exhaust agar discs in a pattern of 8 × 8.
An agardeliverer, one of the machines of the Autoselect‐system is described. This machine allows to pour melted agar automatically into a row of 8 microculture cups of a cassette with 64 cups. By changing the agarcontainer provided for one medium against another container with 8 chambers the machine offers the possibility to deliver 1 to 8 media simultaneously. In this respect the machine gets more and more interest not only for the selection of antibiotic producers, but also for taxonomic, genetic and other studies. Sterile conditions are ensured by sterilizing the head of the machine before starting the work.
The zone reader of the Autoselect‐system enables to measure the 64 inhibition zones of a quadratic bioassay plate with an accuracy of 0,1 mm within 3 minutes. A carriage moves each zone in the light beam. With a special photometrical device 3 defined areas of the inhibition zone can be measured quantitatively by 2 receivers. The indicated values of the diameters result from the analog treatment of the signals. By coupling to a computer the datas of the measuring and other desired informations are printed out.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.