Microfluidic devices and fabrication

Patent metadata

Field	Value
Publication number	US-2017274196-A1
Application number	US-201515508519-A
Country	US
Kind code	A1
Filing date	Sep 3, 2015
Priority date	Sep 3, 2014
Publication date	Sep 28, 2017
Grant date	—

Abstract

Methods for mass production of new microfluidic devices are described. The microfluidic devices may include an array of micro-needles with open channels in fluid communication with multiple reservoirs located within a substrate that supports the micro-needles. The micro-needles are configured so as to sufficiently penetrate the skin in order to collect or sample bodily fluids and transfer the fluids to the reservoirs. The micro-needles may also deliver medicaments into or below the skin.

First claim

1 .- 20 . (canceled)

21 . A replica microfluidic device including:
a plurality of micro-needles across a support member; at least one reservoir in the support member; and a channel providing fluid communication between at least one micro-needle and at least one reservoir, wherein a first aspect ratio to approximately at least 1400:1 of at least one protruding feature of the master die of the micro-fluidic device is also the aspect ratio in the replicated micro-fluidic device.

22 . A device according to claim 21 , wherein the first aspect ratio is to a height of the plurality of micro-needles to a radius of curvature of a tip of the plurality of micro-needles.

23 . A device according to claim 21 , further including a second aspect ratio of a replicated reservoir feature of: a depth to a width is approximately at least 5:1.

24 . A device according to claim 21 , further including a third aspect ratio of a replicated bore or a replicated lumen of: a depth to a diameter is approximately at least 20:1.

25 . A device according to claim 21 , further including at least one fine feature resolution of at less than 500 nanometres of the master die of the microfluidic device is also replicated in the replica micro-fluidic device.

26 . A device according to claim 21 , wherein a height of the plurality of micro-needles of the replica micro-fluidic device is in the approximate range of 650 to 1000 micro-metres.

27 . A device according to claim 21 , wherein a depth of a reservoir of the replica microfluidic device is at least 100 micro-metres.

28 . A device according to claim 21 , wherein a depth of the open channel is in the approximate range of 20 to 100 micrometres.

29 . A device according to claim 21 , wherein each micro-needle of the micro-fluidic device has a yield strength of at least approximately one Newton.

30 . A device according to claim 21 , wherein a surface of the at least one reservoir and the at least one channel is hydrophilic and the other surfaces of the microfluidic device are hydrophobic.

31 . A microneedle for communicating fluids comprising:
a body having at a first end a pointed tip to penetrate an epidermal layer; a base at an opposing second end of the body; and an open channel extending along a side of the body from the first end to the second end, wherein the channel is configured to communicate fluids between the tip and the base of the microneedle.

32 . A patch comprising an array of microneedles according to claim 31 , wherein the plurality of microneedles are supported on a support member.

33 . A patch according to claim 32 , wherein the plurality of open channels extending into the support member form a channel network in communication with at least one reservoir.

34 . A patch according to claim 33 , wherein the channel network is pre-treated to react to a presence of a predetermined substance within the bodily fluid.

35 . A patch according to claim 34 , wherein the pre-treatment is a gel containing at least one reagent for an analyte detection.

36 - 41 . (canceled)

42 . A method of manufacturing a replica micro-needle for communicating fluids according to claim 31 , the method comprising the steps of:
casting a mould in a resilient material from a master die of a microneedle, the die having a microneedle body having at a first end a pointed tip to penetrate an epidermal layer, a base at an opposing second end of the body, and an open channel extending along a side of the body from the first end to the second end; moulding a warm thermoplastic into the mould to form the replica microneedle; and separating the moulded replica microneedle from the mould.

43 . A method of replicating a microfluidic device, including the steps of:
providing a master die of the microfluidic device; casting a mould of the master die; separating the mould from the master die; isothermally heating the mould with a thermoplastic material to a sufficient temperature; maintaining the sufficient temperature; compressing the thermoplastic material into the mould to a sufficient pressure; maintaining the sufficient pressure; reducing the compressing and the heating simultaneously over approximately the same time period; and separating the mould from the replica microfluidic device.

44 . The method according to claim 43 , further including the step of:
producing further replica microfluidic devices by repeating the isothermally to heating steps with the same mould.

45 . A method according to claim 43 , wherein the thermoplastic material is at least one of: a medical grade plastic, a cyclic olefin polymer, Zeonor® 1060R, polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polystyrene, and polycarbonate.

46 . A method according to claim 43 , wherein a mould material is at least one of: a silicone elastomer, elastomeric, silicone rubber, a polydimethylsiloxane (PDMS), SYLGARD 184 Silicone Elastomer, polyurethane elastomeric alloys, rubber, and latex.

Assignees

• Newsouth Innovations Pty Ltd
• Univ Birmingham

Inventors

• Nordon Robert Ernest
• Davies Graham James
• Faraji Rad Zahra
• Anthony Carl John
• Prewett Philip

Classifications

• B01L3/502707

  characterised by the manufacture of the container or its components · CPC title

• B29C39/003

  characterised by the choice of material · CPC title

• B29C33/405

  Elastomers, e.g. rubber (B29C33/50 takes precedence) · CPC title

• A61M2037/0038

  having a channel at the side surface · CPC title

• B29C43/021

  characterised by the shape of the surface · CPC title