Coated microfluidic devices and methods of making

Patent metadata

Field	Value
Publication number	US-9707557-B2
Application number	US-201414486290-A
Country	US
Kind code	B2
Filing date	Sep 15, 2014
Priority date	Jul 3, 2009
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

We describe a method of layer-by-layer deposition of a plurality of layers of material onto the wall or walls of a channel of a microfluidic device, the method comprising: loading a tube with a series of segments of solution, a said segment of solution bearing a material to be deposited; coupling said tube to said microfluidic device; and injecting said segments of solution into said microfluidic device such that said segments of solution pass, in turn, through said channel depositing successive layers of material to perform said layer-by-layer deposition onto said wall or walls of said channel. Embodiments of the methods are particularly useful for automated surface modification of plastic, for example PDMS (Poly(dimethylsiloxane)), microchannels. We also describe methods and apparatus for forming double-emulsions.

First claim

The invention claimed is:

1. A microfluidic device configured to produce a water-in-oil-in-water double emulsion, the device comprising:
a pair of a first, a second and a third fluid flow channels, said pair of the first and second channels providing inlets to a fluid flow junction and said third channel providing an outlet from said fluid flow junction;
wherein said third channel has a surface modification pattern such that a first longitudinal side of said third channel is more hydrophilic than a second, opposite longitudinal side of said third channel and said second longitudinal side of said third channel is more hydrophobic than said first longitudinal side of said third channel; and
wherein said microfluidic device has a first flow focusing region comprising said fluid flow junction to form a water-in-oil emulsion and a second flow focusing region downstream from said first flow focusing region and comprising a second fluid flow junction to form said water-in-oil-in-water double emulsion.

2. The microfluidic device according to claim 1 wherein said third channel provides an inlet channel for said second flow focusing region, and wherein said second flow focusing region comprises fourth and fifth fluid flow channels, said fourth channel providing a further inlet to said second fluid flow junction and said fifth channel providing an outlet from said second fluid flow junction.

3. The microfluidic device according to claim 2 comprising a pair of said fourth fluid flow channels each providing an inlet to said second fluid flow junction.

4. A method of forming a water-in-oil-in-water double emulsion using the microfluidic device of claim 1 , the method comprising controlling emulsion droplet formation steps at said first and second flow focusing regions such that droplet formation at said first and second flow focusing regions occurs in synchronism.

5. A method of using the microfluidic device of claim 1 to form a water-in-oil-in-water double emulsion from droplets of an emulsion in an aqueous stream of fluid, the method comprising:
providing the microfluidic device of claim 1 having at least first, second and third fluid flow channels, said first and second channels providing inlets to a fluid flow junction and said third channel providing an outlet from said fluid flow junction, and wherein said third channel has a surface modification pattern such that a first longitudinal side of said third channel is more hydrophilic than a second, opposite longitudinal side of said third channel and said second longitudinal side of said third channel is more hydrophobic than said first longitudinal side of said third channel;
passing said fluid comprising said droplets through a first flow focusing region comprising a first said fluid flow junction to form a water-in-oil emulsion and through a second flow focusing region downstream from said first flow focusing region to form said water-in-oil-in-water double emulsion.

6. The method according to claim 5 further comprising controlling emulsion droplet formation steps at said first and second flow focusing regions such that droplet formation at said first and second flow focusing regions occurs in synchronism.

7. A microfluidic device for forming a double emulsion, the device comprising:
a first flow focusing region comprising a first fluid flow junction to form a water-in-oil emulsion; and
a second flow focusing region downstream from said first flow focusing region comprising a second fluid flow junction to form a water-in-oil-in-water double emulsion;
wherein said first fluid flow junction comprises first, second and third fluid flow channels, said first and second channels providing inlets to said first fluid flow junction and said third channel providing an outlet from said first fluid flow junction; and
wherein said second flow focusing region comprises said third flow, fourth and fifth fluid flow channels, said third and fourth channels provide inlets to said second fluid flow junction and said fifth channel providing an outlet from said second fluid flow junction;
wherein an internal surface of said third channel is more hydrophobic than an internal surface of said second channel; and
wherein an internal surface of said fifth channel is more hydrophilic than an internal surface of said third channel; and
wherein said third channel has a surface modification pattern such that a first longitudinal side of said third channel is more hydrophilic than a second, opposite longitudinal side of said third channel and said second longitudinal side of said third channel is more hydrophobic than said first longitudinal side of said third channel.

8. The microfluidic device according to claim 7 comprising a pair of said first fluid flow channels providing inlets to said first fluid flow junction, and a pair of said fourth flow channels each providing an inlet to said second fluid flow junction; and wherein an internal surface of said fourth and fifth channel are each more hydrophilic than an internal surface of said third channel.

9. The microfluidic device according to claim 8 wherein said fourth and fifth channels are wider than said third channel.

10. The microfluidic device according to claim 7 , wherein said internal surface of said third channel comprises a layer of material which is more hydrophobic than said internal surface of said second channel, and wherein said internal surface of said fifth channel has a polyelectrolyte multilayer coating such that it is more hydrophilic than said internal surface of said third channel.

Assignees

• Cambridge Entpr Ltd

Inventors

• Bauer Wolfgang Andreas
• Huck Wilhelm T S
• Fischlechner Martin

Classifications

• B01J2219/00837

  comprising coatings other than catalytically active coatings · CPC title

• B01J2219/0097

  Optical sensors · CPC title

• B05D7/22

  to internal surfaces, e.g. of tubes · CPC title

• B01J2219/00783

  Laminate assemblies, i.e. the reactor comprising a stack of plates · CPC title

• Y10T137/8593

  Systems · CPC title