Device and method for handling liquid

Inventors

Reis, Nuno Alexandre Esteves • Tenreiro, Tania Moura Pires De Andrade • Barreiros, Miguel Joao Marques

Assignees

Biosurfit SA

Abstract

A liquid handling device having an axis of rotation about which the device can be rotated to drive liquid flow in the device. The device includes an upstream chamber having an outlet, a downstream chamber including a proximal portion radially inwards of a distal portion and including a first port disposed in the distal portion and a first conduit which connects the outlet of the upstream chamber to the first port of the downstream chamber. The first conduit extends radially inwards to a crest and radially outwards from the crest to the first port of the downstream chamber. A distance between the axis of rotation and the crest is greater than or equal to a distance between the axis of rotation and the outlet of the upstream chamber.

Core Innovation

The invention provides a centrifugal microfluidic liquid-handling device for sequencing liquid flow. The device includes an upstream chamber, a downstream chamber, and a first conduit connecting the upstream and downstream chambers through an upstream chamber outlet and a downstream chamber port. The first conduit includes a radial crest, where the conduit extends radially inwards to the crest and radially outwards from the crest to the first port.

A distance constraint is specified between the axis of rotation and the crest. The distance between the axis of rotation and the crest is greater than or equal to the distance between the axis of rotation and the outlet of the upstream chamber, so that the crest is at or outer to the upstream outlet. This geometry is used together with a filling sequence that fills the first conduit from the downstream chamber to a level equal to a fill level of liquid in the downstream chamber prior to liquid filling from the upstream chamber.

The method further includes filling the first conduit from the upstream chamber to trap gas in the first conduit between respective liquids from the upstream and downstream chambers. The device is then rotated at a first rotational frequency and then at a second rotational frequency greater than the first to vent the trapped gas into the downstream chamber and transfer liquid from the upstream chamber to the downstream chamber. Increasing rotation frequency vents the trapped gas into the downstream chamber so that the upstream liquid is transferred and liquid volumes are combined without stopping rotation.

In additional embodiments, the device adds an unvented cavity with a second port and second conduit to reduce the rotational speed threshold for venting and transfer. By varying rotational frequency, liquid is moved between the downstream chamber and the unvented cavity to promote mixing. The embodiments also include optional dry reagents and a drive system/controller that executes rotational-frequency protocols.

Claims Coverage

The partial content identifies two independent claims. Across these claims, the inventive features focus on conduit geometry with a crest and an axis-to-crest distance constraint, a specific conduit filling sequence that traps gas between upstream and downstream liquids, and a rotational-frequency sequence that vents trapped gas and transfers liquid from the upstream chamber to the downstream chamber, with additional refinements for an unvented cavity and further frequency relationships.

Together, the independent claims cover methods that use a first-conduit geometry with a radial crest and a specified distance constraint relative to the rotation axis, employ a downstream-then-upstream filling sequence to trap gas between liquids, and use an increasing rotational-frequency sequence to vent trapped gas into the downstream chamber to transfer liquid from the upstream chamber to the downstream chamber. The partial content also references an unvented cavity and additional frequency relationships for further liquid transfer and mixing.

Stated Advantages

Documented Applications