Apparatus for detecting micro-organisms

• US 4,801,546 A
• Filed: 02/25/1985
• Issued: 01/31/1989
• Est. Priority Date: 06/29/1983
• Status: Expired due to Fees

• Current Assignee: Metal Box Limited
• Original Assignee: Metal Box Limited
• Inventors: Ackland, Martin R.
• Primary Examiner(s): Scott, Samuel
• Assistant Examiner(s): KAMEN, NOAH P
• Application Number:
  US06/709,035
• Time in Patent Office: 1,436 Days
• Field of Search: 435/34, 435/173, 435/291, 435/299-301, 422/73, 422/99, 422/102, 436/69, 436/150, 204/403, 204/406, 204/412, 324/62, 324/71.1, 324/439, 324/450, 364/497, 364/499
• US Class Current: 435/287.1
• CPC Class Codes: G01N 33/48735 Investigating suspensions of cells, e.g. measuring microbe concentration by chemical means C12Q1/04; colony counters C12M1/34; concentration of particle suspensions in general G01N15/06

Abstract

Apparatus for use in detecting micro-organisms in any one of a plurality of samples of a liquid, such as a food or drink product, e.g. for control of production, comprises a plurality of containers (11) for the sample and a container-mounting member (10) to receive and locate each of the containers, each container being provided with a first electrode of a noble metal (16) and a second electrode, which may be constituted by the body of the container (11), insulated from the first and of a different metal. The container-mounting member (10) is provided with separate contacts (12) and leads for each of the noble metal electrodes (16) and with contacts (922) connected to a common lead for each of the second electrodes. The noble metal electrodes (16) are connected to separate terminals of multiplexing recorder system (40) incorporating a micro-processor (41) for testing the signals to ascertain whether the voltage of the noble metal electrode has dropped below a predetermined value, and if so to display particulars.

Claims

1. Apparatus for use in detecting micro-organisms in any one of a plurality of samples of a substance, comprising a plurality of containers for samples, wherein each container includes a first electrode of a noble metal and a second electrode of a different metal insulated from the first electrode, the electrodes being arranged so as to be contactable with a sample in the container and presenting respective contact surfaces externally of the container, a container-mounting member provided with means for receiving and locating each of the containers and with a first set of contacts adapted to engage the external contact surfaces of the noble metal electrodes and with a separate lead from each of the said first set of contacts adapted for connecting the noble metal electrodes to separate terminals of a multiplexing recorder system and with a second set of contacts adapted to make contact with the external contact surfaces of the second electrodes, all said second set of contacts being connected to a common lead adapted for connecting said second electrodes to a common terminal of a multiplexing recorder system, the container-mounting member being a block formed with recesses each of which is adapted to receive and locate an individual container and being provided with one of each of said two sets of contacts, the container-mounting block having attached to its underside a printed circuit board with leads connecting each of said first set of contacts to an individual contact of a multi-way connector and with leads connecting all of said second set of contacts to a common contact of the multi-way connector.

2. Apparatus according to claim 1, wherein each container comprises a body formed at least in part of said different metal, and that part of the container body constituted the respective second electrode.

3. Apparatus according to claim 1, wherein each container has an upwardly domed bottom through which projects a pin made of or coated with noble metal, constituting the first electrode.

4. Apparatus according to claim 1, wherein each container has a pin made of or coated with noble metal projecting through its side and constituting the first electrode.

5. Apparatus according to claim 1 wherein each container has a body of aluminum and the first electrode is constituted by a gold plated pin projecting through the bottom or side of said container.

6. Apparatus according to claim 1, wherein each container comprises a closure, the first and second electrode for each container being provided in the respective container closure to extend therethrough.

7. Apparatus according to claim 1, wherein each container comprises a closure, the first electrode for each container being provided in the respective container closure to extend therethrough.

8. Apparatus according to claim 1, wherein the multiplexing recorder system comprises an analogue to digital multiplexer arranged to feed voltage signals from the noble metal electrodes of each container in turn to a micro-processor which is programmed to test the signal to ascertain whether the voltage has dropped below a predetermined level and if so to display particulars of the container and of the time taken from commencement of test of the sample to the fall in voltage.