초록 ▼

Porous members can be positioned so as to partially or fully span channels in microfluidic systems. The porous members can be assembled and/or disassembled in situ. The porous members can be made such that pores are separated by connections including but a single molecule at one location, allowing f

Porous members can be positioned so as to partially or fully span channels in microfluidic systems. The porous members can be assembled and/or disassembled in situ. The porous members can be made such that pores are separated by connections including but a single molecule at one location, allowing for a high level of open area in a very small pore size member. The porous member can be made up of colloid particles interconnected with molecular species. These can be used to detect analytes qualitatively and/or quantitatively, or to selectively bind and/or release agents on command for a variety of purposes including first blocking, then opening a channel, concentrating analyte over time followed by release of analyte and detection downstream, etc. Porous members can define valves in multiple-channel systems and, with controlled binding and release of agents at the porous members, these valves can be opened and closed and fluid flow controlled in a multi-channel system. Fluidic systems of the invention can include multiple sensing locations at which different analytes are determined. Systems of the invention provide flexibility for overall microchemical analysis, sequentially, of a variety of agents.

대표청구항 ▼

What is claimed is: 1. An article comprising: a channel able to contain a flowing fluid; and a porous member comprising a network of colloid particles interconnected with molecular species, wherein the porous member comprises at least two pores at least partially spanning the channel, wherein avera

What is claimed is: 1. An article comprising: a channel able to contain a flowing fluid; and a porous member comprising a network of colloid particles interconnected with molecular species, wherein the porous member comprises at least two pores at least partially spanning the channel, wherein average diametric pore size is less than 0.5 micron, wherein the porous member completely spans the channel. 2. The article as in claim 1, wherein the channel has a diametric cross-sectional dimension of less than about 500 microns. 3. The article as in claim 1, wherein the channel has a diametric cross-sectional dimension of less than about 300 microns. 4. The article as in claim 1, wherein the channel has a diametric cross-sectional dimension of less than about 100 microns. 5. The article as in claim 1, wherein the channel has a diametric cross-sectional dimension of less than about 50 microns. 6. The article as in claim 1, wherein the porous member has an average diametric pore size of less than 0.2 micron. 7. The article as in claim 1, wherein the porous member has an average diametric pore size of less than 100 nanometers. 8. The article as in claim 1, wherein the porous member has an average diametric pore size of less than 50 nanometers. 9. The article as in claim 1, wherein the porous member has an average diametric pore size of less than 10 nanometers. 10. The article as in claim 1, wherein the porous member has an average diametric pore size of less than 5 nanometers. 11. The article as in claim 1, wherein the molecular species are fastened to the colloid particles via affinity tag/recognition entity pairs. 12. The article as in claim 1, wherein at least some colloid particles are interconnected with other colloid particles via connections, each connection including, at least one point in the connection, a single molecule. 13. The article as in claim 1, wherein the network of colloid particles are interconnected via oligonucleotides. 14. The article as in claim 1, wherein the porous member has an open area of pore size in the aggregate forming at least 70% diametric cross-sectional area of channel open to flow. 15. The article as in claim 14, wherein the open area is at least 80%. 16. The article as in claim 15, where the open area is at least 90%. 17. The article as in claim 16, wherein the open area is at least 95%. 18. The article as in claim 17, wherein the open area is at least 98%. 19. The article as in claim 1, wherein the channel comprises a groove formed in a surface. 20. The article as in claim 1, wherein the channel is an elongated, enclosed structure having an inlet and an outlet. 21. The article as in claim 20, wherein the channel has a diametric cross-sectional dimension of less than 500 microns and the porous member completely spans the channel and comprises a network of colloid particles interconnected with molecular species and has an open area of pore size in the aggregate forming at least 70% diametric cross-sectional area of the channel open to flow. 22. The article as in claim 21, wherein the porous member has the open area of at least 95% an open area of pore size in the aggregate forms at least 95% diametric cross-sectional area of the channel open to flow and an average diametric pore size of is less than 10 nanometers. 23. The article as in claim 1, wherein the molecular species comprises an oligonucleotide. 24. The article as in claim 1, wherein the molecular species comprises a polymer. 25. The article as in claim 24, wherein the polymer is a synthetic polymer. 26. The article according to claim 1, wherein the article further comprises a means for detecting flow rate. 27. The article according to claim 26, wherein the means for detecting flow rate comprises means for detecting flow drop. 28. The article according to claim 27, wherein the means for detecting flow drop is a differential pressure monitor. 29. The article according to claim 1, wherein the colloidal particle is coated with self assembled monolayer (SAM) or self assembled mixed monolayer. 30. The article according to claim 1, wherein the interconnection can be dissociated by disrupting biological interactions that connect them to the channel. 31. A method comprising: passing a fluid through the article according to claim 1; allowing a chemical, biological, or biochemical agent within the fluid to bind to a binding partner of the agent immobilized relative to the porous member; determining the binding. 32. A method as in claim 31, comprising determining the binding by determining a pressure differential change across the porous member. 33. A method as in claim 31, comprising determining the binding qualitatively. 34. A method as in claim 31, comprising determining the binding quantitatively. 35. A method as in claim 31, wherein the porous member comprises a network of colloid particles interconnected with molecular species spanning a channel through which the fluid is passed. 36. A method as in claim 35, wherein the channel is an elongated, enclosed channel having an inlet and an outlet, and the porous member completely spans the channel such that a fluid flowing through the channel must pass through the porous member. 37. A method as in claim 36, wherein the porous member comprises a network of colloid particles interconnected with molecular species. 38. A method as in claim 37, wherein the molecular species comprise oligonucleotides. 39. A method as in claim 37, wherein the molecular species comprise polymers. 40. A method as in claim 39, wherein the polymer is comprised of synthetic polymers. 41. A method as in claim 37, wherein the porous member comprises a network including colloid particles at least some of which are connected to other colloid particles by a connection including a single molecule. 42. A method as in claim 31, wherein the fluid is an analysis flow of fluid diverted from a main flow of fluid, the method further comprising controlling the main flow of fluid in response to the determining step. 43. A method as in claim 42, wherein the agent is an agent desirably excluded from the main flow of fluid, the method comprising reducing the main flow of fluid in response to the determining step. 44. A method as in claim 43, wherein the fluid is water. 45. A method comprising in the article of claim 1: replacing a first binding partner of a chemical, biological, or biochemical agent immobilized relative to a porous member with a second binding partner without disassembling the porous member relative to the channel. 46. A method comprising in the article of claim 1: passing a fluid through a porous medium; allowing a chemical, biological, or biochemical agent within the fluid to bind to a binding partner of the agent immobilized relative to the porous member; and causing the chemical, biological, or biochemical agent to release from the porous member. 47. A method as in claim 46, further comprising determining the chemical, biological, or biochemical agent downstream from the porous member. 48. A method as in claim 46, comprising concentrating the agent at the porous member during a first period of time, and during a second period of time shorter than the first period of time, releasing agent concentrated at the porous member and determining the agent. 49. A method as in claim 46, comprising allowing the agent to bind to the binding partner to an extent necessary to essentially block flow of fluid through the porous member, then causing the agent to release from the porous member thereby allowing fluid to flow through the porous member. 50. A method as in claim 49, comprising chemically causing the agent to release from the porous member. 51. A method as in claim 49, comprising thermally causing the agent to release from the porous member. 52. A method comprising in the article of claim 1: allowing a first chemical, biological, or biochemical agent to become immobilized relative to a first colloid particle and allowing a second chemical, biological, or biochemical agent to become immobilized relative to a second colloid particle; based at least in part on the identity of the first and second agents, directing the first colloid particle to a first fluid channel and directing the second colloid particle to a second channel. 53. A method comprising in the article of claim 1: allowing a chemical, biological, or biochemical agent to become immobilized relative to a colloid particle; determining at least one characteristic of the agent; based at least in part on the characteristic, directing the colloid particle to a first fluid channel rather than a second fluid channel, each channel capable of receiving the colloid particle prior to the directing step. 54. A method as in claim 53, comprising allowing multiple agents to become immobilized relative to multiple colloid particles, the agents being different from each other, determining at least one characteristic of at least one agent at a first location, then moving at least some of the colloid particles to a second location and determining at least one characteristic of at least one, different agent at the second location. 55. A method comprising in the article of claim 1: allowing a chemical, biological, or biochemical agent to become immobilized relative to a colloid particle; determining at least one characteristic of the agent at a first detection location; and determining at least one characteristic of the agent at a second detection location. 56. A method as in claim 55, comprising determining a first characteristic of the agent at the first location along a fluid flow path, moving a fluid containing the colloid particle along the flow path to the second detection location and determining a second characteristic of the agent at the second location. 57. A method comprising in the article of claim 1: determining the identity of a chemical, biological, or biochemical agent by determining the flow path of a fluid, initially containing the agent, where the fluid has a plurality of flow path options. 58. A method as in claim 57, comprising allowing the agent to bind to a binding partner along the flow path thereby altering the flow path of the fluid.