Automated selection of microorganisms and identification using MALDI

Patent metadata

Field	Value
Publication number	US-9753045-B2
Application number	US-201615383573-A
Country	US
Kind code	B2
Filing date	Dec 19, 2016
Priority date	Mar 30, 2012
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A method and apparatus for locating and selecting a colony of microorganisms on a culture dish and identifying microorganisms in said selected colony using MALDI. The method comprises the automated steps of locating and selecting a colony of microorganisms on a culture dish; obtaining a sample of said selected colony of microorganisms; depositing at least some of said sample of said selected colony of microorganisms on a target plate; and transferring said target plate with said sample in an apparatus for performing MALDI for identification of said sample of said selected colony of microorganisms. A sample of a colony of microorganisms is automatically deposited on a depositing spot such that the sample covers at most approximately half of said one of the depositing spots of the target plate. A suspension of a sample of microorganisms is automatically prepared by automatically picking the sample with a picking tool and submerging the picking tool with said sample in a suspension, after which the picking tool is vibrated in vertical sense only to release the sample from the picking tool.

First claim

The invention claimed is:

1. An apparatus for automatic preparation of a suspension of a sample of microorganisms said apparatus comprising:
a stage for a culture dish comprising said microorganism;
a first and a further picking tool and a positioning device with a picking tool holder for holding a picking tool, said positioning device being arranged for positioning a picking tool in a starting position above the culture dish and for automatically lowering and raising a picking tool towards and away from the culture dish and for positioning a picking tool in a transfer position, respectively;
a suspension tube holder for holding a suspension tube;
an automatic suspension medium dispenser for automatically dispensing a suspension medium in a suspension tube held in the suspension tube holder;
a transferring device for automatically transferring a picking tool from the transfer position of the positioning device to a position above a suspension tube held in the suspension tube holder, and for lowering and raising a picking tool into and away from a suspension medium contained in a suspension tube, and for positioning a picking tool in a waiting position above a suspension tube held in the suspension tube holder, respectively, said transferring device further being arranged for oscillating a picking tool in a linear vertical movement for a period of time;
a turbidity meter for performing measurements of the turbidity of a suspension medium contained in a suspension tube held in the suspension tube holder and for providing a final measurement value indicative of the measured turbidity;
a controller communicatively connected to the positioning device, the transferring device, the automatic suspension medium dispenser and the turbidity meter for automatically controlling the movement of the positioning device, the movement of the transferring device, the operation of the automatic suspension medium dispenser and the operation of the turbidity meter, respectively;
said controller being arranged for:
a) determining whether the final measurement value is above a first threshold value previously stored in a memory of the controller, if yes said controller being arranged for performing step b); or whether the final measurement value is identical to or below the first threshold value and identical to or above a second threshold value previously stored in the memory of the controller, said first threshold value being equal to or greater than the second threshold value, if yes said controller being arranged for performing step c); or whether the final measurement value is below the second threshold value, if yes said controller being arranged for performing step d);
b) controlling the automatic suspension medium dispenser to supply an additional amount of suspension medium into the suspension tube;
c) providing a signal that the suspension tube with the suspension can be removed from the suspension tube holder for further processing; or
d) positioning said further picking tool in said picking tool holder of the positioning device; by said positioning device positioning the further picking tool in the starting position above the culture dish, automatically lowering the further picking tool towards the culture dish into contact with the microorganism to pick up an additional sample of said microorganism, automatically raising the further picking tool with said sample of the microorganism away from the culture dish to the transfer position; by said transferring device automatically transferring said further picking tool with the additional sample of the microorganism from the transfer position of the positioning device to a position above the suspension tube held in the suspension tube holder, lowering said further picking tool with the additional sample of the microorganism into the suspension medium contained in the suspension tube; by the transferring device oscillating the further picking tool in a linear vertical movement for a period of time while the further picking tool with the additional sample of said microorganism is submerged in the suspension medium; and after said period of time has elapsed raising the further picking tool away from the suspension medium contained in the suspension tube to the waiting position; at least after the period of time during which the further picking tool is oscillated has elapsed measuring the turbidity of the suspension medium contained in the suspension tube held in the suspension tube holder by the turbidity meter and providing an additional final measurement value indicative of the measured turbidity; and performing step a).

2. An apparatus for the automatic preparation of a suspension of a sample of microorganisms according to claim 1 , wherein the controller is arranged such that the step of measuring the turbidity of the suspension medium contained in the suspension tube held in the suspension tube holder by the turbidity meter is additionally performed during the period of time during which the picking tool is oscillated, wherein the turbidity meter is arranged for providing an on-line measurement value indicative of the measured turbidity during the period of time during which the picking tool is oscillated to the controller.

3. An apparatus for the automatic preparation of a suspension of a sample of microorganisms according to claim 2 , wherein the controller is arranged for controlling the movement of the transferring device such that a picking tool is raised to the waiting position if during oscillation the on-line measurement value of the turbidity is equal to or lower than the first threshold value and equal to or greater than the second threshold value, and for providing a signal that the suspension tube with the suspension can be removed from the suspension tube holder for further processing.

4. An apparatus for the automatic preparation of a suspension of a sample of microorganisms according to claim 2 , wherein the controller is arranged for controlling the turbidity meter such that measuring the turbidity of the suspension medium contained in the suspension tube held in the suspension tube holder by the turbidity meter is started before the picking tool is submerged in the suspension medium contained in the suspension tube.

Assignees

• Bd Kiestra Bv

Inventors

• Botma Jetze
• Kleefstra Martijn
• Van Der Zee Tino Walter

Classifications

• H01J49/164

  Laser desorption/ionisation, e.g. matrix-assisted laser desorption/ionisation [MALDI] (sample holders H01J49/0418) · CPC title

• G01N2001/045

  Laser ablation; Microwave vaporisation · CPC title

• G01N2035/1032

  Dilution or aliquotting · CPC title

• C12M33/04

  by injection or suction, e.g. using pipettes, syringes, needles (pipettes in general B01L3/02) · CPC title

• G01N35/10 Primary

  Devices for transferring samples {or any liquids} to, in, or from, the analysis apparatus, e.g. suction devices, injection devices {(G01N35/0099 takes precedence)} · CPC title