US 8,304,253 B2Granted

Droplet extraction from a liquid column for on-chip microfluidics

AssigneeAdvanced Liquid Logic, Inc.

InventorsUichong Brandon Yi, Peter Patrick De Guzman, Wayne Liu, Chang-Jin Kim

Life of this patent

Estimating the term…

Loading patent…

Abstract

A refill droplet facilitates the extraction of a droplet laterally from a channel in a microfluidic apparatus. Such extraction allows a discrete band of separated particles or solute molecules to be excised from a fluid stream and processed and analyzed separately. An extraction point is located along the length of the channel and includes an EWOD surface or similar microfluidic technology to extract a droplet. An opening in the channel opposite the extraction means is equipped with microfluidic technology to transport a refill droplet to the opening. The refill droplet is moved into the channel or column to occupy the area previously occupied by the extracted droplet. This prevents distortion or mixing of the bands of particles or molecules within the channel and prevents the draining of any portion of the fluidic system.

Claims8

Dependent claims

A method for extracting a droplet from fluid within a microfluidic column or channel, comprising the steps of:

(a) providing a microfluidic device comprising:
(i) a substrate comprising a channel comprising a liquid column and bounded by:
(1) channel walls;
or
(2) surface property differences that constrain and direct the liquid column;
(ii) an extraction point in the channel comprising an extraction opening and a refill opening opposite the extraction opening;
and
(iii) electrowetting electrodes on the substrate arranged for extracting a droplet from the liquid column at the extraction point;
(b) separating particles or solute molecules of the liquid column into bands or zones;
and
(c) extracting, by use of the electrowetting electrodes, a first droplet comprising a band or zone of particles or solute molecules from the liquid column via the extraction opening while supplying a refill droplet into the liquid column via the refill opening.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 12/090,922Filed 19 Oct 2006 · us provisional application
Priority: 22 Oct 2005
Published: US 2009/0014394 A115 Jan 2009
Granted: 6 Nov 2012
Term ends: Not estimatedThe source records don’t support an estimate.

Classification17 codes

B01L 3/502
Containers for the purpose of retaining a material to be analysed, e.g. test tubes: with fluid transport, e.g. in multi-compartment structures
B01L 3/502792
Specially adapted for droplet or plug flow, e.g. digital microfluidics: for moving individual droplets on a plate, e.g. by locally altering…
B01L 3/502761
By integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g.…
B01L 2200/027
Fluid interfacing between devices or objects, e.g. connectors, inlet details: for microfluidic devices