US 4,478,094 A · Liquid sample handling system

Abstract

An automatic liquid transfer system includes a horizontally translatable table and a vertically translatable set of pipettes. The table accommodates a titer tray having a multiplicity of receptacles to be filled, or holding liquid samples to be diluted, and a rack housing plural rows of disposable tips. During each cycle in a serial dilution process, a fresh set of tips are picked up by the pipettes and used to transfer liquid in a sterile manner from a sample or diluent source to a row of wells in the titer tray, or from one row to a succeeding row of wells where it is mixed with diluent. Thereafter, the tips are discharged back into the rack to maintain sterile conditions during the process. A sensor is provided on the machine to detect whether all of the tips in each set are disengaged and another set successfully picked up.

Claims25

Dependent claims

A machine for automatically transferring at least a portion of liquid sample from one or more liquid-containing receptacles to one or more other receptacles, comprising:

a head assembly translatable between upper and lower positions along a vertical axis;
means for moving said head assembly along said vertical axis;
a plunger assembly mounted on said head assembly for movement therewith, said plunger assembly including a row of pipettes having depending ends for receiving tips, a row of plungers respectively disposed within said pipettes, and means for moving said plungers within said pipettes to vary their internal volumes;
tip ejector means mounted on said head assembly for removing tips disposed on said depending ends of said pipettes;
a table mounted beneath said head for translation along a horizontal axis, said table having work stations spaced along said axis for respectively accommodating a tray having pipette tip-receiving receptacles and one or more trays providing said liquid-containing receptacles and other receptacles;
means for moving said table along said horizontal axis to place any selected one of the receptacles in registry with said pipettes;
and
means for controlling each of said moving means for said head assembly, plungers and table and said tip ejector means to effect transfer of liquid between the liquid-containing receptacles and the other receptacles and to replace tips on the ends of said pipettes with other tips disposed in at least some of the pipette tip-receiving receptacles between predetermined liquid transfer steps.

5 more elements

A method for effecting automatic transfer or dilution of liquid samples between a plurality of liquid receptacles positioned for horizontal movement on a support table and being indexable beneath a vertically movable row of pipettes, comprising the steps of:

(a) charging a predetermined volume of a first liquid into one or more receptacles located at a first work station on said table;
(b) arranging at least a row of pipette tips at a second work station on said table;
(c) moving said table to register said row of pipette tips with the row of pipettes;
(d) lowering said pipettes to engage the tips in said registered row and picking up the engaged tips;
(e) moving said table to register the receptacles of said first work station with said row of pipettes;
(f) inserting the engaged tips in the first liquid in said registered receptacles and withdrawing at least least some of the liquid therefrom into said pipettes;
(g) raising said pipettes;
(h) moving said table to register other receptacles with said pipettes;
(i) lowering said pipettes and expelling the liquid in said pipettes into the other receptacles;
(j) raising said pipettes;
(k) moving the table to bring a selected position at said second work station into alignment with said pipettes;
(l) discharging said engaged tips from said pipettes;
and
(m) repeating steps b through k until a desired number of transfers or dilutions are completed.

11 more elements

A method for effecting automatic transfer or dilution of liquid samples between a plurality of liquid receptacles comprising the steps of:

(a) positioning said plurality of liquid receptacles for horizontal movement on a support table with said receptacles being indexable beneath a row of pipettes at a first work station, at least one of said liquid receptacles containing a predetermined volume of liquid;
(b) positioning a row of pipettes on a head assembly above said support table and vertically reciprocable relative thereto;
(c) arranging at least a row of pipette tips for horizontal movement on said support table at a second work station thereon;
(d) moving said support table to register said row of pipette tips with the pipettes on said head assembly;
(e) lowering said pipettes to engage the tips in the registered row and picking up the engaged tips;
(f) moving said table to index said liquid-containing receptacles at said first work station under said row of pipettes;
(g) inserting the engaged tips in the liquid in said liquid-containing receptacles and withdrawing at least some of the liquid therefrom into said pipettes;
(h) raising said pipettes;
(i) moving said table to index one or more other receptacles under said pipettes;
(j) lowering said pipettes and expelling the liquid in said pipettes into the other receptacles;
(k) raising said pipettes;
(l) moving the table to bring a selected position at said second work station into alignment with said pipettes;
and
(m) discharging said engaged tips from said pipettes.

11 more elements

Dependencies are inferred from the claim text.

Liquid sample handling system

Life of this patent

Liquid sample handling system

Life of this patent

Abstract

Claims25