Patent ID: 7336860
Filing Date: 2008-02-26
Classification: B01L,G01N,Y10T

Abstract:
1. A method of making a microfluidic detection device comprising: (a) a cell body; (b) a flow path through the cell body, the flow path comprising: wherein the central segment has a first junction with the inlet segment and a second junction with the outlet segment and wherein the central segment has a third longitudinal axis, the third longitudinal axis being transverse to the first longitudinal axis and the second longitudinal axis; (c) a first optical fiber having a portion located in the first junction so that a first substantially annular region is formed between the first optical fiber and the inner surface of the central segment, wherein the first optical fiber has a diameter and the first annular region has a length that is approximately between 1-40 times the diameter of the first optical fiber; and (d) a second optical fiber having a portion located in the second junction so that a second substantially annular region is formed between the second optical fiber and the inner surface of the central segment, wherein the second optical fiber has a diameter and the second annular region has a length that is approximately between 1-40 times the diameter of the second optical fiber; wherein the portions of the optical fibers located in the junctions are situated so that fluid entering or exiting the central segment of the flow path flows through one of the annular regions; the method comprising the steps of: (a) coating a first surface of a first and second fused silica wafer with a layer of silicon; (b) transferring a microconduit pattern into the silicon layer on each wafer; (c) transferring the microconduit pattern from the silicon layer to the first surface of each wafer so that the first surface of each silica wafer has the pattern; (d) removing the layer of silicon from each wafer; (e) cleaning the first and the second wafer with both acid and base baths so that the first surface of each wafer is hydrophilic; (f) cleaning the first and second wafers megasonically so that the surfaces of the wafers are more hydrophilic; (g) bringing into contact the first surface of each wafer so that the first surfaces are substantially aligned and form conduits; (h) heating the first and second wafers so that the first and second wafers bond together; (i) filling the flow path with a sacrificial material; (j) dicing the bonded first and second wafers into one or more microfluidic devices; (k) removing the sacrificial material; (l) inserting the first optical fiber into the central segment so that at least a portion of the first optical fiber is located in the first junction; (m) adhering the first optical fiber to the central segment; (n) inserting the second optical fiber into the central segment so that at least a portion of the second optical fiber is located in the second junction; and (o) adhering the second optical fiber to the central segment.