Manipulation of beads in droplets and methods for manipulating droplets

Patent metadata

Field	Value
Publication number	US-9494498-B2
Application number	US-201514978935-A
Country	US
Kind code	B2
Filing date	Dec 22, 2015
Priority date	Apr 18, 2006
Publication date	Nov 15, 2016
Grant date	Nov 15, 2016

Abstract

The invention provides a method of circulating magnetically responsive beads within a droplet in a droplet actuator. The invention also provides methods for splitting droplets. The invention, in one embodiment, makes use of a droplet actuator with top and bottom substrates, a plurality of magnetic fields respectively present proximate the top and bottom substrates, wherein at least one of the magnet fields is selectively alterable, and a plurality of droplet operations electrodes positioned along at least one of the top and bottom surfaces. A droplet is positioned between the top and bottom surfaces and at least one of the magnetic fields is selectively altered.

First claim

We claim:

1. A method of dispensing a bead-containing sub-droplet, the method comprising:
(a) circulating magnetically responsive beads within a droplet on a droplet actuator, wherein circulating comprises:
(i) providing a droplet actuator, comprising:
(1) top and bottom substrates;
(2) a plurality of magnetic fields respectively present proximate the top and bottom substrates, wherein at least one of the magnet fields is selectively alterable; and
(3) a plurality of droplet operations electrodes positioned along at least one of the top and bottom surfaces;

(ii) positioning the droplet comprising magnetically responsive beads between the top and bottom substrates in a gap that is within the magnetic fields; and
(iii) selectively altering at least one of the magnetic fields to circulate the magnetically responsive beads in the droplet; and

(b) using droplet operations to dispense a sub-droplet from the droplet.

2. The method of claim 1 wherein altering at least one of the magnetic fields further comprises activating an electromagnet proximate at least one of the top and bottom surfaces.

3. The method of claim 1 wherein altering at least one of the magnetic fields further comprises activating and deactivating the magnetic fields in a pattern which causes the beads to circulate within the droplet.

4. The method of claim 1 wherein altering at least one of the magnetic fields further comprises activating an electromagnet proximate only one of the top and bottom surfaces.

5. The method of claim 1 further comprising selectively activating at least one of a plurality of electromagnets positioned proximate the top surface.

6. The method of claim 1 further comprising selectively deactivating at least one of a plurality of electromagnets positioned proximate the top surface.

7. The method of claim 1 further comprising selectively activating at least one of a plurality of electromagnets positioned proximate the bottom surface.

8. The method of claim 1 further comprising selectively deactivating at least one of a plurality of electromagnets positioned proximate the bottom surface.

9. The method of claim 1 wherein altering at least one of the magnetic fields further comprises physically altering a position of a magnet emanating the at least one magnetic field.

Assignees

• Advanced Liquid Logic Inc

Inventors

• Pamula Vamsee K
• Sista Ramakrishna
• Srinivasan Vijay
• Pollack Michael G
• Eckhardt Allen

Classifications

• B01F13/0076

  Operations & Transport · mapped topic

• Y10T436/2575

  Volumetric liquid transfer · CPC title

• B01L3/502792

  for moving individual droplets on a plate, e.g. by locally altering surface tension · CPC title

• Y10T436/25625

  Dilution · CPC title

• B01L2300/0861

  Configuration of multiple channels and/or chambers in a single devices · CPC title