Additive channels
Compositions, devices and methods are described for preventing, reducing, controlling or delaying adhesion, adsorption, surface-mediated clot formation, or coagulation in a microfluidic device or chip. In one embodiment, blood (or other fluid with blood components) that contains anticoagulant is introduced into a microfluidic device comprising one or more additive channels containing one or more reagents that will re-activate the native coagulation cascade in the blood that makes contact with it “on-chip” before moving into the experimental region of the chip.
1. A system comprising:
a) a microfluidic device comprising:
an input channel;
an output channel;
a test channel disposed in a solid substrate, wherein said test channel comprises an input portion in fluidic communication with said input channel and an output portion in fluidic communication with said output channel;
endothelial cells disposed within at least one portion of said test channel; and
an output additive channel, wherein said output additive channel is in fluidic communication with said output portion of said test channel;
b) an input channel reservoir in fluidic communication with said input channel;
c) an output additive channel reservoir in fluidic communication with said output additive channel, said output additive channel reservoir comprising one or more reagents that inactivate a native coagulation cascade of blood; and
d) a pressure source adapted to apply pressure to both said input channel reservoir and said output additive channel reservoir.
2. The system of claim 1 , wherein said output additive channel is configured to provide a fluidic resistance that is proportional to the fluidic resistance of said input channel.
3. The system of claim 1 , wherein said output additive channel comprises a first fluidic resistor, and input channel comprises a second fluidic resistor.
4. The system of claim 1 , wherein said endothelial cells are living cells.
5. The system of claim 4 , wherein said living cells form a lumen.
6. A system comprising:
a) a microfluidic device comprising:
an input channel;
an output channel;
a test channel, wherein said test channel comprises an input portion in fluidic communication with said input channel and an output portion in fluidic communication with said output channel;
endothelial cells disposed within at least one portion of said test channel; and
an output additive channel, wherein said output additive channel is in fluidic communication with said output portion of said test channel;
b) an input channel reservoir in fluidic communication with said input channel;
c) an output additive channel reservoir in fluidic communication with said output additive channel, said output additive channel reservoir and comprising one or more reagents that inactivate a native coagulation cascade of blood and is integrated on the microfluidic device; and
d) a pressure source adapted to apply pressure to both said input channel reservoir and said output additive channel reservoir.
7. The system of claim 6 , wherein said output additive channel is configured to provide a fluidic resistance that is proportional to the fluidic resistance of said input channel.
8. The system of claim 6 , wherein said output additive channel comprises a first fluidic resistor, and input channel comprises a second fluidic resistor.
9. The system of claim 6 , wherein said endothelial cells are living cells and said living endothelial cells form a lumen.
10. A system comprising:
a) a microfluidic device comprising:
an input channel;
an output channel;
a test channel, wherein said test channel comprises an input portion in fluidic communication with said input channel and an output portion in fluidic communication with said output channel;
endothelial cells disposed within at least one portion of said test channel; and
an output additive channel, wherein said output additive channel is in fluidic communication with said output portion of said test channel;
b) an input channel reservoir in fluidic communication with said input channel;
c) an output additive channel reservoir in fluidic communication with said output additive channel, said output additive channel reservoir comprising one or more reagents that inactivate a native coagulation cascade of blood; and
d) a pressure source adapted to apply pressure to both said input channel reservoir and said output additive channel reservoir.
11. The system of claim 10 , wherein said output additive channel is configured to provide a fluidic resistance that is proportional to the fluidic resistance of said input channel.
12. The system of claim 10 , wherein said output additive channel comprises a first fluidic resistor, and input channel comprises a second fluidic resistor.
13. The system of claim 10 , wherein said endothelial cells are living cells.
14. The system of claim 13 , wherein said living cells form a lumen.
15. The system of claim 1 , said pressure source is fluidically connected in parallel with both said input channel reservoir and said output additive channel reservoir.
16. The system of claim 6 , said pressure source is fluidically connected in parallel with both said input channel reservoir and said output additive channel reservoir.
17. The system of claim 10 , said pressure source is fluidically connected in parallel with both said input channel reservoir and said output additive channel reservoir.