# US 2018/0024067 A1 · Device and methods of detection of airborne agents > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0024067 A1 - Document ID: US20180024067A1 - Status: Published application - Kind: A1 - Application number: 15/665,095 - Filed: 2017-07-31 - Published: 2018-01-25 - Earliest claimed: 2007-04-27 - Assignees: The Regents of the University of California; The Board of Trustees of the Leland Stanford Junior University - Applicants: The Regents of the University of California; The Board of Trustees of the Leland Stanford Junior University - Inventors: Carl D. Meinhart; Brian Piorek; Seung Joon Lee; Martin Moskovits; Sanjoy Banerjee; Juan Santiago - Web page: https://patentgrep.com/patent/US20180024067A1 ## CPC - G01N 21/658: {enhancement Raman, e.g. surface plasmons} - G01N 21/05: Flow-through cuvettes (G01N21/09 takes precedence; handling fluid samples G01N1/10) - G01N 33/0057: {Warfare agents or explosives} - G01N 21/0332: {with temperature control (control of temperature G05D23/00; cryostats F17C3/08)} - G01N 2021/0346: {Capillary cells; Microcells} - G01N 2201/06113: Coherent sources; lasers - G01N 2201/1087: Focussed scan beam, e.g. laser - Y10S 977/902: Specified use of nanostructure - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract Provided are methods, devices and systems that utilize free-surface fluidics and SERS for analyte detection with high sensitivity and specificity. The molecules can be airborne agents, including but not limited to explosives, narcotics, hazardous chemicals, or other chemical species. The free-surface fluidic architecture is created using an open microchannel, and exhibits a large surface to volume ratio. The free-surface fluidic interface can filter interferent molecules, while concentrating airborne analyte molecules. The microchannel flow enables controlled aggregation of SERS-active probe particles in the flow, thereby enhancing the detector's sensitivity. ## Claims ### Claim 1 A free-surface detection device comprising: a substrate; a fluid flow channel having a first end and a second end located in or on the substrate; at least one free-surface interface region located between the first end and the second end, wherein the free-surface interface region is open on at least one side to atmospheric air comprising an analyte; at least one temperature control element located in the at least one free-surface interface region; and at least one controller in electrical and/or thermal communication with the at least one temperature control element to provide a controlled local evaporation rate, wherein the analyte is concentrated in the fluid flow channel due to said controlled evaporation rate. ### Claim at position 2 2-4. (canceled) ### Claim 5 (depends on 1) The device of claim 1, further comprising at least one valve upstream or downstream of the at least one temperature control element in the fluid flow channel. ### Claim 6 (depends on 1) The device of claim 1, wherein the at least one free-surface region is in the fluid flow channel and wherein the at least one free-surface region comprises at least one wall. ### Claim 7 (depends on 6) The device of claim 6, wherein a surface chemistry of the at least one wall comprises a modification to control fluid flow. ### Claim 8 (depends on 7) The device of claim 7, wherein the modification comprises a change in hydrophobicity and/or hydrophilicity along the at least one wall's surface. ### Claim 9 (depends on 1) The device of claim 1, further comprising: at least one excitation area, wherein electromagnetic energy excites a SERS probe in a fluid in the fluid flow channel; at least one detection area for detecting emitted spectra; and at least one detector in optical communication with the at least one detection area. ### Claim 10 (depends on 9) The device of claim 9, wherein the at least one detector detects the presence of one or more analytes absorbed in a fluid in the fluid flow channel by a technique selected from the group consisting of Raman spectroscopy or surface enhanced Raman scattering (“SERS”) measurements of a probe that is contained in the fluid; electrochemical analysis techniques; fluorescent chemical marker techniques; fluorescence quenching; redox-labeled nucleic acid binding techniques; X-Ray absorption techniques; IR, visible, and UV electromagnetic radiation absorption techniques; mass spectroscopy techniques; liquid chromatography techniques; flame ionization analysis techniques; DNA melting point techniques; and titration analysis techniques. ### Claim 11 (depends on 10) The device of claim 10, wherein the fluid comprises one or more nanoparticles. ### Claim 12 (depends on 11) The device of claim 11, wherein the one or more nanoparticles are functionalized. ### Claim at position 11 13-14. (canceled) ### Claim 15 A free-surface detection device comprising: a fluid flow channel having a first end and a second end; a free-surface interface region located between the first end and the second end, wherein the free-surface interface region is open to atmospheric air comprising nanoparticle colloid; wherein said fluid flow channel further comprises a temperature control element linked to a controller for controlling the local evaporation rate; and wherein nanoparticle colloid concentration is controlled within the fluid flow channel due to said controlled local evaporation rate. ### Claim 16 (depends on 15) The device of claim 15, wherein said nanoparticle colloid aggregates due to controlled nanoparticle concentration.