WO2023057737A1

WO2023057737A1 - Method, apparatus and system for liquid handling

Info

Publication number: WO2023057737A1
Application number: PCT/GB2022/052464
Authority: WO
Inventors: Jason VENN; Adrian HATTON
Original assignee: Veon Scientific Ltd
Priority date: 2021-10-04
Filing date: 2022-09-29
Publication date: 2023-04-13
Also published as: GB202114211D0; GB2611364A

Abstract

An automated liquid handling apparatus is provided, comprising at least one carrier head for engaging at least one pipette tip and aspirating and dispensing liquid; ii. a carrier block for holding and positioning the carrier head; iii. a positioning strut for holding and positioning the carrier block, said carrier block being movable along the longitudinal axis of said positioning strut and said positioning strut being movable to adjust its height from the base of the apparatus; iv. at least one deck being moveable forwards and backwards in a horizontal plane, said deck comprising at least two recessed zones, each of said zones for holding and positioning one plate object, and each of said zones comprising at least one magnet; v. at least two magnetic positioning clips, wherein one magnetic positioning clip is provided for each of said recessed zones, for positioning a plate object within said recessed zone and optionally; vi. at least two plate objects, each of said plate objects held in one of said recessed zones of said deck, and said at least two plate objects including a. one plate object for holding pipette tips; b. one plate object for holding at least one sample source and at least one sample destination.

Description

Method, Apparatus and System for Liquid Handling

FIELD

The invention relates to liquid handling and in particular to methods, apparatuses and systems for automated liquid handling on small scale.

BACKGROUND

Liquid handling is a major part of scientific, especially chemical and biochemical, research, development and production. For example, there are a myriad of analytical techniques used every day in laboratories all over the world, but most, if not all, existing systems need a means of preparing and introducing a sample.

Despite its fundamental importance, there are still a number of “pain points” in laboratories around sample preparation and liquid handling. In particular, there is a subset of lab procedures where the large scale fully automated sample preparation systems are not appropriate/effective, and what remains is manual liquid handling, which has its own drawbacks. This subset of lab procedures is not at present served by any automated liquid handling system or apparatus.

There are some exceptionally advanced liquid handling systems on the market which could in principle handle virtually any liquid handling task or workflow, however, the relative value of the markets shows that in practice these systems are not suitable for all automated processes. The manual liquid handling market dwarfs the automated liquid handling market in revenue. Hence there are clearly problems with the existing automated liquid handling systems. Specifically, there are problems to be overcome in their use in a large subset of procedures where manual handling is, at present, still the method of choice for scientists and researchers.

It is an object of the current invention to provide an apparatus, system and method that can compete with the convenience and speed of the manual pipette, while improving on its use for accuracy and precision. It is further an object that the apparatus, system and method be simpler and quicker to set up than the large-scale automated systems on the market.

The invention provides apparatuses, systems and methods for overcoming the problems of the art in small scale automated liquid handling. SUMMARY OF INVENTION

In a first aspect, the invention provides an automated liquid handling apparatus according to the claims.

In a second aspect, the invention provides an automated liquid handling system according to the claims.

In a third aspect, the invention provides a method of automated liquid handling, as defined in the claims. Preferably this is a method for liquid sample preparation.

In another aspect the methods of the invention are computer-implemented methods.

In a further aspect, the invention provides a computer program comprising liquid handling software code for performing the methods according to the claims, when the computer program is run on a computer.

In a further aspect, the invention provides a computer program comprising liquid handling software code for performing the computer-implemented method according to the preferred embodiments, when the computer program is run on a computer.

In yet another aspect the invention provides a computer-readable medium comprising the computer program according to the claims.

In yet another aspect the invention provides a computer-readable medium comprising liquid handling software code executable to cause a computer to perform the computer- implemented method according to the preferred embodiments when the software code is executed on a computer.

In another aspect the invention provides for the use of at least one of a. the apparatus according to the claims; b. the system according to the claims; c. the computer program according to the claims; and/or d. the computer-readable medium according to the claims; in liquid handling, preferably in the preparation of a liquid sample. All features described in connection with any aspect of the invention can be used with any other aspect of the invention.

BRIEF DESCRIPTION OF FIGURES

The invention will be further described with reference to a preferred embodiment, as shown in the drawings in which:

FIG. 1a shows front diagonal view of apparatus - closed (CAD drawing)

FIG. 1 b shows front diagonal view of apparatus - open (CAD drawing)

FIG. 2a shows front central view of apparatus - closed (CAD drawing)

FIG. 2b shows front central view of apparatus - open (CAD drawing)

FIG. 2c shows front diagonal view of apparatus - closed (CAD drawing)

FIG. 2d shows rear central view of apparatus - closed (CAD drawing)

FIG. 3 shows side view of apparatus (CAD drawing)

FIG. 4a shows cut through view of a typical Deck

FIG. 4b shows isometric view of a typical three-zone Deck

FIG. 4c shows plan view of a typical three-zone Deck, showing recessed lip

FIG. 4d shows plan view of Deck with circle marking channels for magnetic positioning clip

FIG. 4e shows plan view of Deck with circle marking aperture corner relief

FIG. 4f shows cut through view of Deck with optional zone ID markings

FIG. 4g shows plan view of Deck with magnetic positioning clips in position

FIG. 4h shows plan view of Deck with magnetic positioning clips showing magnets and one clip out of position

FIG. 4i shows view of Deck with magnetic positioning clips out of position

FIG. 4j shows corner of recessed zone of deck and offset magnets

FIG. 5 shows magnetic positioning clip without magnet

FIG. 6 shows typical tip waste receptacle and lid

FIG. 7 shows a tip adapter plate

FIG. 8 shows a magnetic bead adapter plate

FIG. 9a shows a magazine adapter plate in greyscale

FIG. 9b shows a magazine adapter plate in line drawing

FIG. 10 shows a micro-centrifuge tube adapter plate

FIG. 11a shows a pipette tip adapter in greyscale

FIG. 11 b shows a pipette tip adapter in line drawing

FIG. 12a shows a plate object in greyscale

FIG. 12b shows a plate object in line drawing FIG 13a-c show a typical three-zone deck configuration Z1 - Plate for Magazine Objects Z2 - Plate for Micro centrifuge tubes Z3 - Tip Adapter Plate & Racked Pipette Tips in isometric and plan views, CAD and line drawings

FIG. 14a-c show a typical carrier head (pipette module) with cover

FIG. 15 shows a typical workflow to run the apparatus

DETAILED DESCRIPTION

General definitions

Throughout this application terms should be interpreted according to their standard meaning in the art unless specified otherwise. The following terms should be construed according to their standard meanings, as set out below.

As used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise. Thus for example, a reference to "a method" includes one or more methods, and/or steps of the type described herein and/or which will become apparent to those persons skilled in the art upon reading this disclosure and so forth.

The term “approximately” or “about” in connection with a number is intended to mean “in the region of”, i.e. within normal tolerance of the stated value. In other words, a value that the skilled worker in the relevant field would round up or round down to reach the “approximate” value. For example, a value in the range of 95 to 104 would be “approximately 100”, or 0.96 to 1.04 would be “approximately 1”.

The term “at least” when used in connection with a number has its standard meaning, i.e. means that number is the minimum value for the specified parameter/component. For example “at least one destination” means there is one or more destination and discloses the options of one destination or more than one destination being present.

The term “comprising” should be construed as meaning “including but not limited to”. The term “comprising” also discloses mixtures, processes and the like “consisting essentially of’ the specified features and “consisting of” the specified features. For example, an apparatus disclosed herein as comprising parts (a) to (d) also discloses an apparatus consisting of parts (a) to (d). The term “greater than” when used in connection with a number has its standard meaning, i.e. means that the specified parameter has a value higher than the specified number.

The term “not greater than” or “no more than” when used in connection with a number has its standard meaning, i.e. means that the specified parameter has a maximum value equal to the specified number.

The term “in the range from A to B” has its standard meaning, i.e. the value of the parameter is a minimum of A and a maximum of B.

The terms X-axis, Y-axis and Z-axis have their standard meanings, representing the three dimensions or directions of linear movement. The terms XY-plane, XZ plane and YZ plane have their standard meanings representing three planes, for example rotational movement about the x-axis would be rotational movement in the YZ plane.

The term “less than” when used in connection with a number has its standard meaning, i.e. means that the specified parameter has a value lower than the specified number.

The term “multiple” has its standard meaning, i.e. at least 2, more preferably at least 3.

The term “no less than” or “not less than” when used in connection with a number has its standard meaning, i.e. means that the specified parameter has a minimum value equal to the specified number.

The term “optionally” has its standard meaning, i.e. means that the specified feature is not essential and may or may not be present. Optional components or process steps disclose the claimed product or process including and not including the optional feature.

The term “performed using” as for example in “liquid handling is performed using” has its standard meaning, i.e. when the claimed process is carried out, the specified feature applies.

Features which are described herein with reference only to a single aspect or embodiment of the invention apply equally to all other aspects and embodiments of the invention.

Hence features from one aspect or embodiment may be combined with features from another aspect or embodiment. Apparatus

The invention provides an automated liquid handling apparatus comprising: i. at least one carrier head for engaging at least one pipette tip and aspirating and dispensing liquid; ii. a carrier block for holding and positioning the carrier head; iii. a positioning strut for holding and positioning the carrier block, said carrier block being movable along the longitudinal axis of said positioning strut and said positioning strut being movable to adjust its height from the base of the apparatus; iv. at least one deck being moveable forwards and backwards in a horizontal plane, said deck comprising at least two recessed zones, each of said zones for holding and positioning one plate object, and each of said zones comprising at least one magnet; v. at least two magnetic positioning clips, wherein one magnetic positioning clip is provided for each of said recessed zones, for positioning a plate object within said recessed zone; optionally further comprising vi. at least two plate objects, each of said plate objects held in one of said recessed zones of said deck, said at least two plate objects including a. one plate object for holding pipette tips; b. one plate object for holding at least one sample source and at least one sample destination.

The apparatus preferably further comprises a receptacle for used pipette tips.

The current invention provides a small form automated liquid handling/pipette apparatus and system to bridge the gap between manual pipetting and large-scale, complex and fully automated products currently available on the market. The advantages of the current invention include its form factor, the nature of the user interaction, for example, that the apparatus does the liquid transfer with relative precision and a simple graphical user interface to control and configure the apparatus.

In comparison with industrial size fully automated pipette systems, the apparatus of the current invention is simpler and quicker to set up a discreet liquid transfer, or to run even a complex workflow, and is also physically more convenient to use because its small size allows for it to be placed directly in the relevant workspace where it is easily and quickly accessible. Figure 15 illustrates the type of workflow required to set up a transfer.

Manual pipetting is labour intensive and prone to human error. It requires the user to be able to pipette reliably using a well-established pipetting technique, but there are often errors in aspiration volumes, dispensing volumes, accuracy in dispense location, omissions in protocol, carry over etc. In contrast, the apparatus of the present disclosure can provide samples reproducibly with improved precision, accuracy and speed compared with a human operator.

In comparison with manual pipetting, the apparatus according to the present disclosure is far less labour-intensive for the liquid transfer steps, as well as reducing repetition. Use of the apparatus of the invention also allows human operators to spend time on other activities, for example, analysis of scientific data, or planning further scientific work, depending on the value proposition for a given user or company.

Size of Apparatus

The apparatus according to the invention may typically be, for example, around 40cm wide, by 40cm high, by 40cm deep. To put this in context, typically, the apparatus may be the size of a microwave oven, for example. The small form-factor of the apparatus means it is especially suitable for benchtop applications and is portable, i.e. can easily be moved from laboratory to laboratory. The input power is typically 24vdc, which helps with usage cases such as mobile and ‘pop up’ labs. When using mains, an external AC/DC adapter is used.

The vertical door opening/closing mechanism of the enclosed apparatus provides easy access and means that the footprint of the apparatus remains that of the apparatus itself, without additional clearance space being needed to operate the apparatus.

The small form-factor of the apparatus also means that the apparatus fits within a standard medical safety cabinet or a laminar flow cabinet, and can operate within these. If located inside one of these cabinets, the apparatus is typically operated from outside the cabinet using a control unit according to the system of the invention. In its smallest form the apparatus will accommodate two or three recessed zones for placement of pipette tips, sample source (e.g. sample liquid) and sample destination(s) (target).

Carrier Head

The apparatus comprises at least one carrier head. The carrier head is removably located on the carrier block. The carrier head is for engaging, for example collecting and holding, at least one pipette tip and aspirating and dispensing liquid. The carrier head is removable from the apparatus and may also be referred to as a “pipette module”. The carrier head contains the components require to aspirate and dispense the liquid by means of air displacement. For example, a carrier head with a positive displacement approach could be used.

The carrier head comprises at least one pipette tip adapter which can interface with a variety of pipette tips of varying size, for example 0.2-1 OOOpI tips, such as 0.2-2pl, 1 -1 Opl, 2-20pl, 1 -50pl, 10-1 OOpI, 20-200pl, 50-250pl, or 100-1 OOOpI pipette tips, amongst other available ranges. The capacity of a pipette tip refers to the maximum volume of liquid a pipette tip would take up e.g. a 0.2 pl tip would take up a maximum of 0.2 pl liquid.

Preferably, the carrier head comprises an exchangeable tip adapter, so that it is compatible with pipette tips from different manufacturers.

The carrier head may have a single channel or multi-channel configuration. Single channel is preferred.

In an embodiment where more than one deck is present in the apparatus then either a multi-channel carrier head or multiple single-channel carrier heads may be used, wherein more than one pipette tip may be collected and multiple pipetting operations can be performed simultaneously. For example, where the apparatus comprises two decks, then in one preferred embodiment a multi-channel dual carrier head may be used, for collecting and holding two pipette tips. Equally preferred, two single-channel carrier heads may be used.

Typical Configurations include, for example:

Single Channel Pipette - Single Deck (preferred)

Single Channel Pipette - Dual Deck Dual - Single Channel Pipettes - Single Deck

Dual - Single Channel Pipettes - Dual Deck

Multi-channel Pipette - Single Deck

Multi-channel Pipette - Dual Deck

Dual - Multi-channel Pipettes - Single Deck

Dual - Multi-channel Pipettes - Dual Deck

Generally, it is preferred that the carrier head has a key way affixing mechanism, such that it simply slides into the carrier block via a mechanical interface and is secured by a magnetic arrangement between the carrier block and carrier head. Preferably the securing magnets are neodymium magnets and the magnetic force is such that it can be overcome by manual “pull force” when dismounting the carrier head. A removable carrier head allows for service and recalibration. The removal of the carrier head also allows for exchange with a carrier head supporting different pipetting volume ranges.

The carrier head may optionally comprise an outer casing to protect the channels and pipette tip adaptor and other components from e.g. dust, when dismounted and not in use. It is preferred in all aspects and embodiments that the carrier head is encased with such an outer casing.

Pipette Tip

Pipette tips of varying size may be used with a carrier head, for example 0.2-1000pl tips, such as 0.2-2pl, 1 -1 Opl, 2-20pl, 1 -50pl, 10-1 OOpI, 20-200pl, 50-250pl, or 100-1 OOOpI pipette tips.

The volume of liquid that may be aspirated/dispensed is dependent upon the size of the pipette tip used and the carrier head displacement range, but typically is in the range of 0.1-1000pl.

Generally, pipette tips are “push-fit” and are engaged by the carrier head being lowered onto the pipette tip by means of the positioning strut (gantry) being lowered. The force of the carrier head pressing into the empty pipette tip results in the pipette tip being picked up (engaged) by the carrier head. The carrier head may also use torque level control to apply the desired force when engaging the tip. This is achieved by the motor controller measuring the motor current and motor encoder position to determine when resistance from the tip is observed and when step loss starts to occur.

Generally, the carrier head uses a given tip adapter fitted. The tip adapter is inserted into the pipette tip.

Once the pipette tip is in place (engaged) on the carrier head, liquid may be aspirated into the pipette tip, and later dispensed from the tip, by means of air displacement (pressure control) within the carrier head. This aspiration and dispensing of liquid uses electromechanical principles of air displacement and means that are well known to the skilled person in the art.

Carrier Block

The apparatus comprises a carrier block, also referred to as a “transblock”. The carrier block is for holding and positioning the carrier head. The carrier block is mobile and can move back and forth (left and right), along the longitudinal axis of the positioning strut (also known as a “gantry”) in the horizontal plane.

Typically, the carrier block may be a machined component, such as a machined aluminium component, that slides onto the positioning strut (gantry). The carrier block is driven horizontally (between left and right sides), for example using a motorised belt and pulley system. Other drive systems can be used within the skilled person’s knowledge of the art, for example drive along the y-axis could be effected with a lead screw and nut.

Preferably, the carrier block may contain a flag to establish the home/datum position of the carrier block on initialisation.

The carrier block interfaces with the carrier head. It is preferred that the carrier block and carrier head are secured together by means of a magnetic arrangement. It is further preferred that the carrier block has a PCB (printed circuit board) to interface, with a plug/socket arrangement, with the carrier head. The PCB is typically a small interfacing electronic board with a receptacle to allow for power and communication . The PCB may be connected to the positioning strut (gantry), for example via a flexible ribbon cable.

The Carrier Block may be dismounted from the apparatus in order, for example, to clean it, to exchange it, to recalibrate or otherwise replace it. Positioning Strut

The apparatus comprises a positioning strut, also known as a gantry. The positioning strut is for holding and positioning the carrier block, said carrier block being movable along the longitudinal axis of said positioning strut and said positioning strut being movable to adjust its height from the base of the apparatus. In other words, the gantry moves up and down (vertically, along the z-axis of the apparatus).

Typically, the positioning strut would be supported by two vertical pillars which form a structural frame of e.g. extruded aluminium. The vertical pillars may, for example, be machined with a 1 mm deep channel to accommodate a linear rail system. This assembly of strut and pillars forms the core structure so that the positioning strut can traverse up and down. Suitably, for example, two vertical linear rails interface with four linear carriages spaced apart to minimise skew. In such an example, the assembly comprises of brackets to which the four linear carriages are secured.

The positioning strut is driven vertically, for example by using a lead screw and nut, which in turn may be driven by a motorised belt and pulley system (or driven directly without a belt). The positioning strut preferably contains a flag to establish the home/datum position of the strut (gantry) on initialisation.

The positioning strut may, for example, comprise of an aluminium extrusion or other structural parts machined with a horizontal 1mm deep channel to accommodate a linear rail system. End brackets and motor brackets secure the drive system comprising of feedback encoders, stepper motors, belts and pulleys to drive the carrier block loaded with the carrier head. Preferably, a PCB may be mounted on the positioning strut to provide electrical and communications connectivity and to facilitate the home/datum function with an optical sensor.

Deck

The deck of the apparatus according to the invention comprises at least two recessed zones, each zone for holding and positioning one plate object. Each recessed zone comprises at least one magnet.

Preferably the deck includes two to four recessed zones, more preferably two or three recessed zones. In the most preferred embodiment, applicable to all aspects of the invention, the deck includes only three recessed zones, i.e. exactly three recessed zones.

The recessed zones preferably do not have a base, but have a lip or an inwardly protruding edge inset, which can prevent the Plate Object from falling through the deck. In other words, preferably the recessed zones of the deck comprise a hole or aperture that matches or partially matches the dimensions of the plate object. The magnetic positioning clip aligns with the magnet of each recessed zone to hold the Plate Object securely and precisely in position within the recessed zone. The Plate Object is smaller than the aperture in the recessed zone of the deck, but the magnetic positioning clip provides force to control and position the plate object in the opposing corner of the recessed zone.

This approach improves the centralisation of the pipette tip based on the plate object’s geometry.

The deck is moveable forwards and backwards in a horizontal plane, i.e. corresponding to movement along the x-axis of the apparatus. Movement of the deck also provides user functionality by presenting the deck forward for loading and unloading. The deck is elevated, which means it is located vertically above the base level of the apparatus. The elevation of the deck allows deep objects to protrude through the deck within the available space below.

Generally, a removeable drip tray may be positioned under the deck to capture liquid spillages during operation of the apparatus.

Preferably the deck is suspended at a height sufficient to allow objects such as pipette tips to protrude through the deck and hang below the level of the deck.

It is also possible to use the plate object to control the position in the Z-plane of the consumable that will be held by the plate object. The plate object can be thinner or thicker in order to add elevation, and will typically be designed for a specific end-application.

Some will be made of PTFE, PEEK (inert materials), others will be Aluminium for durability, or so as to be heated or chilled to help maintain a given sample temperature.

The apparatus may be operated with some empty recessed zones, i.e. there may be more recessed zones in the deck than there are plate objects. The deck can hold as many plate objects as there are recessed zones, in total. For example, a deck having three recessed zones can hold a maximum of three plate objects. During typical operation of the apparatus it is expected that at least two plate objects are held in the recessed zones of the deck, and therefore at least two recessed zones, according to the apparatus of the invention. One zone could act as both the source and target/destination for the most simple and rudimentary of transfers. More typically there would be three recessed zones. Each plate object is held in a separate recessed zone of the deck. Of the two plate objects that are the minimum required to operate the apparatus, these must include: a. one plate object for holding pipette tips; b. one plate object for holding at least one sample source and at least one sample destination.

In a typical liquid handling procedure for the apparatus of the invention, liquid is transferred, i.e. is moved from one location to another, for example from source to destination (target).

In its most preferred form, the apparatus contains one deck containing only three recessed zones, i.e. exactly three recessed zones. This is the most preferred embodiment of the invention, in all aspects. In this most preferred embodiment applicable to all aspects of the invention, when the apparatus is in use then each of the three recessed zones of the deck contains one plate object, so that the deck holds: a. one plate object for holding pipette tips; b. one plate object for holding at least one sample source; c. one plate object for holding at least one sample destination.

Most preferably the plate objects are as defined according to ANSI SLAS 2-2004 (R2012) - formerly recognised as ANSI/SBS 2-2004. Plate objects for use with the apparatus of the invention are ANSI compatible, i.e. have XY dimensions according to the ANSI standard in order to enable the fitment of the ANSI compatible plate objects with the deck.

The apparatus comprises at least one deck. In a preferred embodiment the apparatus contains only one deck. In an alternative embodiment the apparatus comprises more than one deck, for example, contains two decks.

In the embodiment where more than one deck is contained in the apparatus, for example, where there are two decks contained in the apparatus, it is preferred that the decks are arranged in a vertical configuration where one deck is elevated from the base of the apparatus at a higher level than the other deck. Each deck in a multi-deck embodiment has the same characteristics and properties as described for a single deck, i.e. is movable forwards and backwards in a horizontal plane, and contains at least two, preferably two or three recessed zones (most preferably only three recessed zones).

Suitable materials for the decks of the invention include machined aluminium.

Movement of the deck may be accomplished, for example, by using a stepper motor, feedback encoder and belt/pulley system. Preferably all the motors of the apparatus have encoded feedback which allows closed loop motor control. Other movement methods are known to the skilled person, for example using a lead screw and nut. Preferably the deck includes an optical sensor to flag positioning data.

Preferably each recessed zone of the deck has an optional key way to facilitate orientation of its plate object, in use. Other preferred features include a chamfered edge to help guide the plate object into the recessed zone.

Optionally each zone may have an identification label.

Magnetic Positioning Clip

The apparatus of the invention includes at least two magnetic positioning clips, one for each recessed zone. For operation of the apparatus it is necessary that there is one magnetic positioning clip per plate object, for positioning said plate object within its recessed zone in the deck.

Each recessed zone comprises one magnet. The magnet of the recessed zone is positioned so that when the magnetic clip is applied to the plate object in the recessed zone, the two magnets are slightly offset from each other. This offset positioning causes a “pull” force as the two magnets try to align together. This “pull” force results in the magnetic positioning clip in turn applying a continuous force to the Plate Object which keeps the Plate Object flush against a particular edge or corner of the recessed zone. Optionally there may be a milled channel in the deck that the magnetic positioning clip runs in, which controls the direction of travel and force applied. The magnetic clip typically runs in a channel in the corner of the deck and, using magnetic forces, generates a tension on the object inserted into the recessed zone. The diameter and length of the magnet determines the overall pull force. This tension ensures the object is held securely and pushes the plate object into the diagonally opposing corner to provide optimal positioning in the zone. This ensures correlation of the pipette tip and plate object geometry. The magnetic clip approach eliminates the requirement for parts that are commonly known to wear during usage such as springs.

The linear force generated is opposed to the magnetic field.

Typically the magnetic positioning clip is applied at the rear corner of the plate object. For example, the magnetic positioning clip might be applied at the rear left corner of the recessed zone (in plan view) with the magnet of the recessed zone positioned so that the magnetic positioning clip applies a diagonal force to the plate object that keeps this as far to the right and front as possible, so that its front right corner is located tight against the front right corner of the recessed zone. The plate object is thus securely positioned, held in place by the magnetic “pull” force, and located exactly against the front right corner of the recessed zone.

The magnets used in the magnetic positioning clip and in the recessed zone typically are Neodynium magnets, for example a clip magnet which is circular with a diameter of around 8mm and thickness of around 2mm with N42 1 kg pull would be suitable, with a recessed zone magnet also circular with diameter 8mm and thickness 5mm and N42 1 .9kg pull. The skilled person will be able to vary the individual magnet sizes and strengths within their ability in the art, in order to find combinations which provide the required pull force to keep a given plate object in position.

Plate Objects

Plate objects for use with the apparatus of the invention are ANSI compatible, i.e. have XY dimensions according to the ANSI standard in order to enable the fitment of the plate objects with the deck. Plate objects suitable for use with the apparatus of the invention are preferably as defined according to ANSI SLAS 2-2004 (R2012) - formerly recognised as ANSI/SBS 2-2004.

Plate objects are generally either machined or moulded parts that can hold a consumable object or sample. For example, a microplate. Plate objects can be customised, within the skilled person’s abilities, to accommodate existing or new consumable objects. Typical plate objects may include, for example, tip adapters, tube adapters, accessory adapters, reservoir adapters, magazine adapters or custom adapters.

Consumable objects that are typically useful with the apparatus of the invention include, for example, sample vials, PCR tubes, PCR strips, centrifuge tubes, microcentrifuge tubes, reservoirs and pipette tips. All such consumable objects can be retained in a plate object.

For example, a tip adaptor plate object can be used which engages into a recessed zone of the deck in the same way as general plate objects. The tip adaptor plate object is designed to engage with the plastic tray in which pipette tips are typically supplied. The tip adaptor plate object ensures that the pipette tips are positioned in the deck precisely with respect to their XY and Z positions. This tip adaptor plate object also includes retaining clips to ensure that the pipette tips tray remains seated during the process of engaging the carrier head into the pipette tip.

As described above, the minimum functional operation would be to use two recessed zones with two plate objects, one holding tips and the other holding two tubes. In this simple workflow the apparatus could aspirate liquid from one tube into the other tube. However, the most typical usage case would be to aspirate from an source in one zone to a destination in another zone. Using a three-zone workflow in this way unlocks a broader spectrum of laboratory workflows.

Examples of zone and plate object combinations include (Z = Zone):

(Z1) Tips (Z2) Microplate (Z3) Microplate

(Z1) Tips (Z2) Tube (Z3) Microplate

(Z1) Tips (Z2) Microplate (Z3) Tube

(Z1) Tips (Z2) Tube (Z3) Tube

(Z1 ) Tips (Z2) Any Object (Z3) Any Object

The apparatus can perform sequential transfers to multiple objects (replication), for example. (Z1 ) Tips (Z2) Object (Z3) Object 1 , (Z3) Object 2, (Z3) Object 3 and so on.

Plate objects can be positioned in any recessed zone.

XYZ Platform The deck, positioning strut and carrier block of the apparatus may be considered analogous to an XYZ platform, this being an electro-mechanical system with encoded feedback. Viewed from this perspective, the deck (or decks) is mobile along the x-axis and as described previously this traverses front/back (horizontally) within the apparatus. The carrier block (also known as a transblock) is mobile along the y-axis and traverses left/right (horizontally) along the positioning strut, within the apparatus. The positioning strut (also known as a gantry) is mobile along the z-axis and traverses up/down (vertically) within the apparatus.

Movement back/forth along each of the x, y and z axes may be accomplished by any means known to the skilled person. For example, belt driven stages or belt driven steppers may be used, or a lead screw and nut, magnetic linear drive or other linear technology.

For movement back/forth along the y-axis (positioning strut/gantry) it is preferable to minimise axial movement (“play”) in the components by using at least one lead screw, for example using two leads screws with electronic synchronisation. However, in the smallest form embodiment of the apparatus it is preferred to use only one lead screw. It is further preferred to use a multipoint arrangement of linear carriages to control skew, for example, to use four linear carriages.

For positioning calibration, the XYZ datums are set using three flags and optoelectronic sensors, one on each axis. Calibration is then set by measuring the touch point of all three planes when a calibration tool connected to the carrier block comes into contact with the deck.

Receptacle for used pipette tips

The apparatus according to the invention may optionally comprise a receptacle for used pipette tips. It is preferred that at least one said receptacle is included, and more preferred that two such receptacles are included.

Generally, the receptacles are transparent so that the user has visibility of the level of waste. However, in the enclosed apparatus of the invention, in a preferred embodiment, the receptacles may comprise waste bags in order to manage e.g. contaminated waste more effectively and safely. In the enclosed apparatus of the invention, the waste receptacles are sealed, access being by means of an aperture within the enclosure, through which the pipette tip may pass. There may be a tip hook within the receptacle to remove the used tip in this embodiment.

The receptacle(s) are typically secured with an optional magnetic interface.

The receptacle(s) preferably include an optical sensor or switch which enables the system to know whether a receptacle has been engaged or disengaged. Where two receptacles are included, this allows the system to recognise that one receptacle has been disengaged (e.g. for emptying) and it must use the other.

Additional Components/Features

One or more of the following additional components or features may optionally be comprised by the apparatus of the invention. These components or features may be present individually or in any combination in the apparatus according to the invention.

Enclosure, including door

Preferably the apparatus according to the invention is fully enclosed, with at least one door for access. The door is preferably located on the front of the enclosure and opens/closes vertically. Enclosure of the apparatus helps contribute to maintaining a good environment to prepare samples and prevent contamination, and can also act as a safety enclosure.

Magnetic latch or Linear Rail mounting

Advantageously the enclosure door is held open or held closed using magnets to apply a holding force in order to latch the door at the open/closed position. Alternatively, and equally advantageously, the door may be mounted on a linear rail system with tension. Such a linear rail system allows the door to maintain a position between the end -stops of fully open and fully closed.

Handle and locking positions for transportation

Preferably the mobile components of the apparatus may be locked in position to prevent movement of the individual parts during transportation. Optionally the apparatus comprises a handle mounted on the exterior of the enclosure, for carrying the apparatus by hand. Integrated manual control button panel or touch panel

Preferably the apparatus comprises an integrated button panel or touch panel. This is different from the separate control unit described with reference to the system of the invention. For the enclosed apparatus, the integrated button panel or touch panel is built into the exterior of the enclosure. For all aspects and embodiments containing this feature, it is incorporated within the apparatus and is not separable from the apparatus.

In the button panel embodiment there are preferably four or five individual buttons set into the exterior of the enclosure, for manual execution of operations such as: power, stop, pause, resume, reset.

The touch panel embodiment provides a simplified graphical use interface with touchscreen buttons for manual execution of operations such as power, stop, pause, resume reset. The touch panel further provides at least one options menu to select or set-up and execute programs and provide means of configuring the apparatus.

Side-panel monitoring and instrument status indication system

The enclosed apparatus optionally further comprises an illumination system for instrument status indication. In this embodiment at least a portion of the side panels of the enclosure is transparent and colour illumination through at least a portion of these transparent sections indicates the status of the apparatus. Different colours and/or different illumination patterns may be used to indicate differing status. For example, red flashing light to indicate program malfunction, blue flashing light to indicate program in operation, solid green light to indicate program complete, etc. This feature helps an operator know the status from a distance, within the lab.

Internal LED illumination and UV light source

The enclosed apparatus may comprise an internal LED illumination array. This array provides illumination of the enclosure for user visibility. Typically, the array comprises at least one white LED located in the top of the enclosed work space.

Preferably the enclosed apparatus further comprises at least one ultra-violet light source. More preferably the enclosed apparatus further comprises an array of UV LEDs that can assist with cleaning and/or sterilisation of the apparatus. UV radiation can deactivate biological molecules and therefore can be useful in decontamination. The UV LED array or light source may be separate from or integrated with the illumination array.

Coatings

It is preferred in all aspects and embodiments that the apparatus is coated with an antimicrobial or anti-viral coating.

System comprising apparatus and control unit

The apparatus according to the invention may advantageously and preferably be operated by a separate control unit such as a computer with suitable data connections to the apparatus, which is configured to control and/or operate the apparatus. The apparatus and separate control unit together may be referred to as the liquid handling system according to the invention.

Suitable control units include, for example, a Microsoft tablet, or apple/android/linux system. For example, a tablet, laptop or PC with or without touch technology.

The separate control unit is particularly advantageous for working with applications that require the apparatus to be located inside a medical safety cabinet, for example.

The control unit facilitates general device operation and all functional operations as well as calibration of the apparatus.

Methods

The invention further provides a method of automated liquid handling comprising: i. providing a system according to the invention; and ii. operating the apparatus to a. aspirate and dispense a fixed volume of liquid; or b. aspirate a fixed volume of liquid and dispense at least one aliquot from that volume.

The operation of the apparatus preferably comprises at least one of the following steps: operating the apparatus to dispense a fixed volume of liquid; or operating the apparatus to provide at least one aliquot of a liquid sample; operating the apparatus to perform a forward pipetting operation; operating the apparatus to perform a reverse pipetting operation; and/or operating the apparatus to perform a touch dispense operation; and optionally performing one or more further processing steps.

Preferably this is a method for preparation of at least one liquid sample. More preferably, further fixed volumes or multiple aliquots are delivered in order to prepare multiple liquid samples. For example, between 2-100 aliquots may be delivered from a single uptake of liquid sample.

In practice, the methods of operation of the apparatus start by engaging a pipette tip and end by ejecting the tip.

In an embodiment applicable to all aspects of the invention, any of the pipetting modes can be selected. The volume of liquid taken up in the pipette tip is sufficient to deliver a fixed volume of liquid or multiple aliquots into multiple destination vials. For example the method may preferably comprise: uptake of liquid sample into a pipette tip; repositioning of the carrier head by means of at least one of: movement of the carrier block along the positioning strut, and/or movement of the positioning strut to adjust its height above the base of the apparatus; repositioning of the sample destination by means of movement of the deck backwards or forwards; output from the pipette tip of one aliquot of liquid sample into a sample destination; further repositioning of the carrier head by means of at least one of: movement of the carrier block along the positioning strut, and/or movement of the positioning strut to adjust its height above the base of the apparatus;

- further repositioning of the sample destination by means of movement of the deck backwards or forwards;

- further output from the pipette tip of one aliquot of liquid sample into a sample destination; repetition of the further repositioning and output steps until the desired number of aliquots are delivered.

For a forward dispensing operation the method preferably comprises: a volume of air (blow out volume) is drawn into the pipette tip initially, before any liquid; - the pipette tip is submersed into liquid (this can be achieved, for example, by means of liquid level detection using the sensing of pressure changes inside the pipette tip);

- the precise amount of sample liquid required is drawn into the pipette tip;

- the pipette tip is moved to the sample destination; the volume of liquid in the pipette tip including the initial blow out volume is dispensed (the purpose of the blowout volume is to ensure the pipette tip is fully evacuated from liquid thus maximising the pipetting accuracy and repeatability).

For a reverse dispensing operation the method preferably comprises:

- the pipette tip is submersed into liquid (this can be achieved, for example, by means of liquid level detection using the sensing of pressure changes inside the pipette tip); a volume of liquid greater than the desired dispensing volume is drawn up into the pipette tip;

- the pipette tip is moved to the sample destination;

- the liquid in the pipette tip is partially dispensed down to the desired dispense volume where it promptly stops;

- the pipette tip is not fully evacuated and some liquid remains in the tip;

In some cases e.g. with highly viscous samples this method can offer a more precise pipetting.

For a touch dispensing operation the method preferably comprises:

- the pipette tip is submersed into liquid (this can be achieved, for example, by means of liquid level detection using the sensing of pressure changes inside the pipette tip); a volume of liquid greater than the desired dispensing volume is drawn up into the pipette tip; and either

- the pipette tip is moved to the sample destination; a volume of liquid is dispensed with a sufficiently low dispense flow rate such that a droplet forms on the end of the pipette tip;

- the pipette tip is moved toward the surface of the sample receptable until it is within such proximity that the droplet makes contact with its surface; when the droplet makes contact with the surface of the sample receptacle surface tension will detach the droplet from the pipette tip and transfer it to the sample receptacle or

- the pipette tip is moved to the sample destination;

- the pipette tip is moved toward the surface of the sample receptable until it is within suitable proximity such that a droplet would make contact with its surface; a volume of liquid is dispensed with a sufficiently low dispense flow rate such that a droplet forms on the end of the pipette tip; when the droplet makes contact with the surface of the object surface tension will detach the droplet from the pipette tip and transfer it to the object.

This mode of operation is well suited to applications where the desired sample volume is so small that a continuous liquid stream cannot be created due the surface tensions.

It is preferred that the method further comprises operating a computer, with suitable data connections to the apparatus, to run software to: i. obtain information regarding one or more parameters pertaining to the liquid sample to be prepared; ii. calculate the volume of liquid to be taken into the pipette tip; iii. control uptake of liquid into the pipette tip, and output of liquid into at least one sample destination; iv. optionally control performance of one or more further processing steps.

Preferably step (i) may comprise one or more of the following steps:

(a) Factor user selected plate object data and geometry;

(b) Factor user selected tip object data and geometry;

(c) Output a set of instructions and object data via a scripting language to the apparatus.

Computer Program

The invention further provides a computer program comprising liquid handling software code for performing the method of the invention, when the computer program is run on a computer. The easy to use computer program allows for the use of the apparatus by people without wide knowledge of automated liquid handling. The program provides for the handling and preparation of liquid samples by the apparatus according to the invention, automated to perform liquid transfers without manual intervention. The program based on preloaded information prepares the instructions to be sent to the apparatus, optionally including calibration.

Manual intervention may be needed for example in steps such as loading, unloading, changing objects etc.

The computer program will use geometric and co-ordinate data provided by the software to determine where the carrier head needs to move based on the specified sample and destination vials. The computer program uses “path planning” to calculate a safe path of travel from its current position to the next position taking into account the plate objects loaded onto the deck. This ensures that the pipette tip is moved to a safe travel z position and that the X and Y movement path avoid any obstructions.

Computer-readable Medium

The invention further provides a computer-readable medium comprising the computer program of the invention.

The invention further provides a computer-readable medium comprising liquid handling software code executable to cause a computer to perform the computer-implemented method of the invention when the software code is executed on a computer.

Examples of typical computer-readable media include CD-ROM and USB Drive.

Uses

Further provided is the use of at least one of a. the apparatus according to the invention; b. the system according to the invention; c. the computer program according to the invention; and/or d. the computer-readable medium according to the invention; in liquid handling, preferably in the preparation of at least one liquid sample, optionally for use in a further process. Preferred Process Applications

There are a number of typical sample preparation processes/workflows that lend themselves to the benefits of automation and can be performed on/by the Apparatus.

These include, but are not limited too:

• Plate Replication.

• Plate reformatting.

• Serial Dilution.

• Cherry picking.

Plate replication involves the transfer of liquid from one plate object to another maintaining the same layout within the destination plate object.

Plate reformatting involves transferring liquid from one plate object to whilst also rearranging (reformatting) the layout of samples positions within the destination plate object.

Serial dilution is a stepwise process for diluting samples to decreasing concentrations. The process is started with a volume of a high concentration solution being transferred into a new plate object location. Diluent is added to that same location to achieve the desired concentration, the resultant solution can then be used itself as the high concentration sample and can be used to produce the next serial dilution. The process is repeated for all required serial dilutions.

Cherry picking describes the process of transferring liquid from specific but non-uniform (seemingly random) plate object locations and dispensing them into other non-uniform locations. This process may be repeated for all required transfers.

The uses according to the invention may preferably comprise use in one or more of plate replication, plate reformatting, serial dilution and/or cherry picking processes.

Whilst the invention has been described with reference to preferred embodiments, it will be appreciated that various modifications are possible within the scope of the invention.

All prior teachings acknowledged above are hereby incorporated by reference. No acknowledgement of any prior published document herein should be taken to be an admission or representation that the teaching thereof was common general knowledge in the United Kingdom or elsewhere at the date hereof.

DETAILED DESCRIPTION OF FIGURES

Figure 1 shows an embodiment (1) of the apparatus according to the invention, in its closed configuration in figure 1a and open configuration in figure 1b. The carrier head (2) is visible on the carrier block (3) mounted on the positioning strut (4). In this embodiment there are three plate objects (5, 6, 7): one plate object (5) for providing empty pipette tips; one plate object (6) for providing liquid(s) to be collected into the pipette tip engaged by the carrier head; and one plate object (7) for receiving one or more aliquots of liquid sample dispensed from the pipette tip. Typically, the plate object (7) for receiving aliquot(s) would contain vials of the appropriate size. In addition, there is a bin (8) for used pipette tips following dispense of liquid.

Figure 2 shows an embodiment of the apparatus, from a central front position, closed in figure 2a and open in figure 2b, then from a front diagonal and rear central perspective (both closed). The pipette tip bins are more clearly visible in figures 2a and 2b. The carrier head (2) is holding a pipette tip (9) in figure 2.

Figure 3 shows a side view of the apparatus.

Figure 4 shows various views of a typical deck, a cut-through, isometric view and plan views, showing the lip in the recessed zones, the magnetic positioning clips, channel and aperture corner relief, zone ID markings, how the magnetic positioning clips fit into place and their magnets with the magnets of the recessed zones.

Figure 5 shows the magnetic positioning clip without magnet.

Figure 6 shows a typical tip waste receptable.

Figures 7-12 show different plate objects including adapter plate objects.

FIG 13a-c show a typical three-zone deck configuration Z1 - Plate for Magazine Objects Z2 - Plate for Micro centrifuge tubes Z3 - Tip Adapter Plate & Racked Pipette Tips in isometric and plan views, CAD and line drawings. FIG. 14a-c show a typical carrier head (pipette module) with cover.

FIG. 15 shows a typical workflow to run the apparatus.

List of Elements shown in Figures:

1 embodiment of the apparatus according to the invention

2 carrier head

3 carrier block

4 positioning strut

5 plate object for providing empty pipette tips

6 plate object containing liquid(s) to be collected into the pipette tip

7 plate object for receiving one or more aliquots of liquid sample dispensed from the pipette tip

8 bin (receptacle) for used pipette tips

9 pipette tip

EXAMPLES

Example 1 : Preparation for qPCR Diagnostics of SARS-CoV-2 Patient Samples qPCR (quantitative polymerase chain reaction) is a well-established molecular biology and diagnostics technique for the amplification or DNA/RNA to allow for detection. In the case of diagnostic testing the specific gene sequence of a virus can be amplified to detectable levels from a patient sample specimen allowing the determination of a positive or negative clinical result.

In the case of this example, a patient sample would be collected by means or anterior nasal swab and oropharyngeal swab. The swab would then be transferred to a sample buffer tube which will be suitable for subsequent use in the apparatus.

The sample buffer tube contains a VTM (viral transport media) so that it can be sent to a central laboratory for qPCR analysis. The VTM ensures that that the sample does not pose a risk of infection, but ensures that the viral gene sequence is not destroyed and can later be amplified.

Multiple patient samples would be collected in a central/localised laboratory ready for sample preparation by the apparatus. The apparatus can be used to prepare small or larger sample batches as required. The sample preparation steps include transferring a fixed volume of sample liquid (i.e. 5pl) into a PCR reaction tube, which contains all the necessary chemistry (primers, probes, polymerase etc.) for the PCR process to occur when subjected to the thermal cycling conditions.

When the central/localised laboratory are ready to analyse the patient samples, it is first necessary to perform the sample preparation, which is carried out by the apparatus in the following steps:

• The pipette tips are inserted into the pipette tip rack adaptor plate object.

• The pipette tip rack adaptor is loaded into a zone of the deck in the apparatus.

• Patient sample buffer tubes are loaded into a tube rack plate object, their lids are removed as are the swabs.

• The tube rack plate object is loaded into a zone of the deck in the apparatus.

• PCR reaction tubes are inserted into a tube rack adaptor plate object.

• The tube rack adaptor plate object is loaded into a zone of the deck in the apparatus.

• The software program which controls the apparatus is programmed by the user to specify the number of samples which are to be processed.

• The apparatus processing each sample sequentially as follows: o A new/unused pipette tip is collected/engaged by the carrier head; o The carrier head is moved to the desired patient sample buffer tube (sample source); o A fixed volume of sample liquid is aspirated (i.e. 5 p I); o The carrier head is moved to the desired PCR reaction tube (sample destination); o The fixed volume of sample liquid in the pipette tip is dispensed into the PCR reaction tube; o The carrier head is moved into the receptacle for used pipette tips; o The pipette tip is ejected from the carrier head by means of a hooking mechanism and is ready to repeat the process for the next sample.

Once the sample preparation process has been carried out by the apparatus, the PCR reaction tubes can be transferred into a qPCR thermal cycler instrument for the PCR process to be performed. The thermal cycler will apply cycles of high and low temperature to the samples which combined with the chemistry in the PCR reaction tube will induce the DNA/RNA amplification process. The sample preparation process could be performed manually using a handheld pipette, however the apparatus according to the invention provides improved precision and repeatability, with greater user walk-away time.

Claims

CLAIMS:

1 . An automated liquid handling apparatus comprising: i. at least one carrier head for engaging at least one pipette tip and aspirating and dispensing liquid; ii. a carrier block for holding and positioning the carrier head; iii. a positioning strut for holding and positioning the carrier block, said carrier block being movable along the longitudinal axis of said positioning strut and said positioning strut being movable to adjust its height from the base of the apparatus; iv. at least one deck being moveable forwards and backwards in a horizontal plane, said deck comprising at least two recessed zones, each of said zones for holding and positioning one plate object, and each of said zones comprising at least one magnet; v. at least two magnetic positioning clips, wherein one magnetic positioning clip is provided for each of said recessed zones, for positioning a plate object within said recessed zone and optionally vi. at least two plate objects, each of said plate objects held in one of said recessed zones of said deck, and said at least two plate objects including a. one plate object for holding pipette tips; b. one plate object for holding at least one sample source and at least one sample destination.

2. The apparatus as defined in claim 1 wherein the said optional plate objects (vi) are present.

3. The apparatus as defined in any preceding claim wherein said deck comprises at least three recessed zones and at least three magnetic positioning clips.

4. The apparatus as defined in any preceding claim wherein said deck comprises only three recessed zones and only three magnetic positioning clips.

5. The apparatus as defined in claim 3 or claim 4 wherein the said optional plate objects (vi) are present and include at least three plate objects, each of said plate objects held in one of said recessed zones of said deck, and said at least three plate objects including a. one plate object for holding pipette tips; b. one plate object for holding at least one sample source; and c. one plate object for holding at least one sample destination. The apparatus as defined in any preceding claim wherein the number of said plate objects is the same as the number of said recessed zones. The apparatus as defined in any preceding claim wherein said carrier block, said positioning strut and said at least one deck together provide an XYZ platform. The apparatus as defined in any preceding claim wherein the said carrier head has a slide-fit mechanical interface with said carrier block and is secured using magnetic forces, preferably wherein said magnetic forces are provided by two or more neodymium magnets. The apparatus as defined in any preceding claim wherein said carrier head has a single channel configuration for collecting and holding only one pipette tip, or wherein said carrier head has a multi-channel configuration for collecting and holding two or more pipette tips. The apparatus as defined in any preceding claim wherein each of said magnetic positioning clips comprises a neodymium magnet, preferably a magnetic strip. The apparatus as defined in any preceding claim wherein, in use, each of said magnetic positioning clips is located at one of the rear corners of each of said recessed zones. The apparatus as defined in any preceding claim having only one deck, or having two decks arranged in a vertical configuration with one deck elevated above the other deck. The apparatus as defined in any preceding claim, further comprising at least one receptacle for used pipette tips, preferably two receptacles. The apparatus as defined in any preceding claim, being fully enclosed by an enclosure comprising an access door. The apparatus as defined in any preceding claim, further comprising an integrated manual control button panel or touch panel, wherein if the apparatus is enclosed then said panel is integrated into the exterior of the enclosure. An automated liquid handling system comprising: i. the apparatus as defined in any preceding claim; ii. a control unit with suitable data connections to the apparatus, said control unit configured to operate said apparatus. A method of liquid handling comprising: i. providing a system according to claim 16; ii. operating the apparatus to; a. aspirate and dispense a fixed volume of liquid; or b. aspirate a fixed volume of liquid and dispense at least one aliquot from that volume; and optionally performing one or more further processing steps. The method according to claim 17, further comprising at least one of the following steps:

1 . operating the apparatus to dispense a fixed volume of liquid;

2. operating the apparatus to provide at least one aliquot of a liquid sample;

3. operating the apparatus to perform a forward pipetting operation;

4. operating the apparatus to perform a reverse pipetting operation; and/or

5. operating the apparatus to perform a touch dispense operation; and optionally performing one or more further processing steps. The method according to claim 17 or claim 18, being a method for preparation of a liquid sample. The method according to any of claims 17 to 19, further comprising: operating a computer, with suitable data connections to the apparatus, to run software to: i. obtain information regarding one or more parameters pertaining to the liquid sample to be prepared; ii. calculate the volume of liquid to be taken into the pipette tip; iii. control uptake of liquid into the pipette tip, and output of liquid into at least one sample destination; iv. optionally control performance of one or more further processing steps. A computer program comprising liquid handling software code for performing the method as claimed in any of claims 17 to 20 when the computer program is run on a computer. A computer-readable medium comprising the computer program of claim 21. Use of at least one of: a. the apparatus as claimed in any of claims 1-15; b. the system as claimed in claim 16; c. the computer program according to claim 21; and/or d. the computer-readable medium of claim 22; in liquid handling, preferably in the preparation of at least one liquid sample, optionally for use in a further process.