MICROPIPETTING APPARATUS

• US 3,807,235 A
• Filed: 10/06/1972
• Issued: 04/30/1974
• Est. Priority Date: 10/13/1971
• Status: Expired due to Term

• Current Assignee: Ivan Lefkovits, Otto Kamber
• Original Assignee: Ivan Lefkovits, Otto Kamber
• Inventors: Lefkovits, Ivan, Kamber, Otto
• Primary Examiner(s): Swisher, S. Clement
• Application Number:
  US05/295,646
• Time in Patent Office: 571 Days
• Field of Search: 222/263 73/425,4R,425.4P,425.6 141/21,25,26,27
• US Class Current: 73/863.32
• CPC Class Codes: B01L 3/021 Pipettes, i.e. with only one conduit for withdrawing and redistributing liquids
• CPC Class Codes: G01N 2035/00237 Handling microquantities of analyte, e.g. microvalves, capillary networks

Abstract

Apparatus for withdrawing minute quantities of a liquid medium into a liquid collecting apparatus. The so-obtained liquid medium is then transferred from the liquid collecting apparatus into a vessel containing another medium which interacts with the liquid medium collected to give information about the latter.

Claims

1. A micropipetting apparatus for pipetting a liquid comprising a liquid receiving cannula secured to a carrier plate and extending downwardly from the underside thereof, the upper end of said cannula extending to the upperside of the carrier plate, a pump membrane disposed over the upperside of said carrier plate, a second plate provided with an opening overlying the pump membrane, said opening being in registry with said upper end of said cannula, said opening being provided by an indentation and a bore in a second plate in axial alignment and in communication with each other, said indentation extending from the surface of the side of said second plate overlying the pump membrane to a point between the last mentioned surface and the surface of the upperside of the second plate, said bore extending from the surface of the upper side of said second plate to said point, the diameter of the portion of the bore at the surface of the upper side of the second plate being less than the diameter of the portion of the indentation at the surface of the side of the second plate overlying the pump membrane, means for moving the pump membrane so that a portion thereof is drawn into said indentation in the second plate whereby withdrawal of a predetermined amount of said liquid into said cannula occurs.

2. A micropipetting apparatus as defined in claim 1 which comprises a plurality of cannulas and openings whereby a plurality of substantially equal amounts of said liquid is withdrawn from said vessel containing said liquid.

3. A micropipetting apparatus as defined in claim 2 wherein the means for moving the pump membrane is provided by a suction chamber overlying the pump membrane.

4. A micropipetting apparatus as defined in claim 3 wherein the plurality of cannulas are disposed in a staggered relationship.

5. A micropipetting apparatus for pipetting a liquid comprising a liquid receiving cannula secured to a carrier plate and extending downwardly from the underside thereof, the upper end of said cannula extending to the upperside of the carrier plate, a pump membrane Disposed over the upperside of said carrier plate, a second plate provided with an opening overlying the pump membrane, said opening being in registry with said upper end of said cannula, means for moving the pump membrane so that a portion thereof is drawn into said opening in the second plate whereby withdrawal of a predetermined amount of said liquid from a vessel containing said liquid into said cannula occurs and wherein the opening in the second plate comprise a large opening in the side of the plate adjacent the pump membrane and a smaller opening extending therefrom, the upper end of said smaller opening being in communication with a suction chamber.

6. A micropipetting apparatus as defined in claim 5 wherein the magnitude of the liquid drawn into the cannula is of the order of a microliter.

7. A micropipetting apparatus as defined in claim 5 wherein the magnitude of the liquid drawn into the cannula is of the order of a microliter.