Method of making a multiwell test plate

• US 4,948,442 A
• Filed: 06/18/1985
• Issued: 08/14/1990
• Est. Priority Date: 06/18/1985
• Status: Expired due to Term

• Current Assignee: Whatman, Inc. (GE Healthcare Technologies, Inc.)
• Original Assignee: Polyfiltronics, Inc. (GE Healthcare Technologies, Inc.)
• Inventors: Manns, Roy
• Primary Examiner(s): Warden, Robert J.
• Assistant Examiner(s): Johnston, Jill
• Application Number:
  US06/745,877
• Time in Patent Office: 1,883 Days
• Field of Search: 156/73.1, 156/73.3, 156/268, 156/308.4, 156/309.6, 422/101
• US Class Current: 156/73.1
• CPC Class Codes: B01L 3/50255 Multi-well filtration
• CPC Class Codes: G01N 1/4077 by other techniques involving separation of suspended solids
• CPC Class Codes: Y10S 436/809 Multifield plates or multicontainer arrays
• CPC Class Codes: Y10T 156/1082 Partial cutting bonded sandwich [e.g., grooving or incising]

Abstract

A micro-titre test plate including a thermoplastic incubation tray having an array of a plurality of wells extending therethrough, filter means, and a thermoplastic harvester tray for supporting the filter sheet. The harvester tray has a plurality of apertures therethrough arranged to be registerable with the bottoms of the wells in the incubation tray. To prevent cross-talk between the wells along the filter, the facing surfaces of the harvester tray and incubation tray are provided with mating ridges and grooves circumscribing the juncture of each well and aperture. In one embodiment, the ridges and grooves are thermally bonded to one another to provide a fluid-impervious barrier trapping respective filter disks in the juncture of each well and aperture. In another embodiment, the harvester tray is formed of a pair of apertured, thermoplastic sheets nested with respective thermally bonded grooves and ridges to trap the filter, the harvester tray being not necessarily bonded to the incubation tray.

Claims

1. Method of making a micro-titre filter plate having a substantially flat, thermoplastic culture tray with a plurality of wells arranged in a regular array, said wells extending between open ends on opposite flat surfaces of said tray, and a substantially flat, thermoplastic harvester tray having a like plurality of openings therethrough, said method comprising the steps of

circumscribing each of said openings on one, surface of said harvester tray with one of a mating groove and ridge;

circumscribing each of said wells on one surface of said culture tray with the other of said mating groove and ridge;

positioning a filtration sheet across all of said openings on said one surface of said harvester tray;

positioning said harvester tray with respect to said culture tray with said one surface of each adjacent the other so that each said opening is adjacent and registered with each said well, and said filtration sheet is disposed between said harvester tray and said culture tray;

compressing the positioned trays and filtration sheet perpendicularly to the planes of said trays until the top edge of each said ridge is substantially in contact with the interior surface of each said groove; and

thermally bonding each said top edge of each said ridge with each said interior surface of each said groove, thereby to form a fluid-impervious wall circumscribing the juncture of each registered well and opening.

2. Method as defined in claim 1 wherein said bonding is ultrasonic bonding.

3. Method as defined in claim 1 wherein a thermoplastic vacuum manifold is disposed adjacent the opposite surface of said harvester tray, and including the step of thermally bonding said vacuum manifold to the periphery of said harvester tray.

4. Method of making a micro-titre filter plate having a substantially flat, thermoplastic culture tray with a plurality of wells arranged in a regular array, said wells extending between open ends on opposite flat surfaces of said tray, and a substantially flat, thermoplastic harvester tray formed of a pair of substantially flat plates each having a like plurality of registered openings therethrough, said method comprising the steps of

circumscribing each of said wells on one surface of said culture tray with one of a first mating channel and first ridge;

circumscribing a first surface of a first of said plates with the other of said first mating channel and first ridge so that each said first ridge and channel fits tightly together to form a substantially fluid-impervious barrier means;

circumscribing the opposite surface of said first plate with one of a second mating channel and second ridge circumscribing each of said openings in said first of said plates;

circumscribing a facing surface of said second plate with the other of said second mating channel and ridge circumscribing each of said openings in said second plate;

positioning a thermoplastic filtration sheet between said plates across all of said openings;

positioning said plates with respect one another so that each said opening in each plate is adjacent and registered with a corresponding opening in the other plate;

compressing the positioned plates perpendicularly to the planes thereof until the top edge of each said second ridge is substantially in contact with the interior surface of each said second channel; and

thermally bonding each said top edge of each said second ridge with each said interior surface of each said second channel thereby to form a fluid-impervious wall circumscribing the juncture of each pair of registered openings.

5. Method as claimed in claim 4 including the step of scoring said plates so that said trays may be broken apart along said scoring into segements each containing an integral multiple of a registered pair of openings and the portion of said filtration sheet trapped therein.