# US 2014/0150890 A1 · Method For Washing a Microfluidic Cavity > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150890 A1 - Document ID: US20140150890A1 - Status: Published application - Kind: A1 - Application number: 13/877,719 - Filed: 2011-10-04 - Published: 2014-06-05 - Earliest claimed: 2010-10-07 - Assignees: Boehringer Ingelheim Microparts GmbH - Inventors: Wolfgang Stoeters; Ying Yu; Silke Knoll - Web page: https://patentgrep.com/patent/US20140150890A1 ## CPC - B08B 3/04: Cleaning involving contact with liquid - B01L 3/5027: {by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip} - B01L 3/502738: {characterised by integrated valves (throttle valves in microfluidic sample containers B01L3/502746)} - B01L 13/02: {for receptacle or instruments} - B01L 2200/141: Preventing contamination, tampering - Y10T 137/0424: Liquid cleaning or flushing - B08B: CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL - B01L: CHEMICAL OR PHYSICAL LABORATORY APPARATUS FOR GENERAL USE - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract The invention relates to a method for washing at least one cavity (20′) in a microfluidic component, the cavity (20′) containing a first liquid (F1) and at least one second liquid (F2) being supplied to the cavity (20′) for washing. According to the invention an air bubble (L) is supplied to the cavity (20′) before the washing liquid (F2) is introduced. The air bubble (L), which acts as a virtual barrier layer between the first liquid (F1) and the washing liquid (F2) that follows it enables the washing efficiency to be increased considerably. Overall, this method leads to a saving in washing liquid (F2) and washing time. Moreover, a microfluidic component is proposed for carrying out the method. ## Claims ### Claim 1 Method for washing at least one cavity (20, 20′) in a microfluidic component (1, 1′), the cavity (20, 20′) containing a first liquid (F1) and the cavity (20, 20′) being supplied with at least one second liquid (F2) for washing, characterised in that the cavity (20, 20′) is supplied with a gas (L) before the washing liquid (F2) is introduced. ### Claim 2 (depends on 1) Method according to claim 1, characterised in that the gas is passed through the cavity (20, 20′) in the form of a bubble (L) with a defined volume. ### Claim 3 (depends on 2) Method according to claim 2, characterised in that the gas bubble (L) has a volume that is smaller than the volume of the cavity (20, 20′). ### Claim 4 (depends on 1) Method according to claim 1, characterised in that the volume of the gas bubble (L) corresponds to approximately 40% to 60%, preferably approximately 50%, of the volume of the cavity (20, 20′). ### Claim 5 (depends on 1) Method according to claim 1, characterised in that the gas (L) is air. ### Claim 6 (depends on 1) Method according to claim 1, characterised in that the introduction of gas (L) and subsequent liquid (F2) for washing is repeated several times. ### Claim 7 Microfluidic component (1, 1′) for carrying out a method for washing at least one cavity (20, 20′) in a microfluidic component (1, 1′), the cavity (20, 20′) containing a first liquid (F1) and the cavity (20, 20′) being supplied with at least one second liquid (F2) for washing, characterised in that the cavity (20, 20′) is supplied with a gas (L) before the washing liquid (F2) is introduced, said microfluidic component containing at least one first cavity (10), which is filled with a liquid (F2) for washing at least one second cavity (20, 20′), and means (40, 50a, 50b) for providing a fluidic connection between the at least one first (10) and the at least one second cavity (20, 20′), characterised in that, viewed in the direction of flow (S) of the liquid (F2), at least one further cavity (30) is arranged between the first (10) and the second cavity (20, 20′), which cavity (30) is filled with a gas (L). ### Claim 8 (depends on 7) Microfluidic component (1, 1′) according to claim 7, characterised in that the at least one further cavity (30) filled with gas (L) has a volume that is smaller than the volume of the at least one second cavity (20, 20′) that is to be washed. ### Claim 9 (depends on 7) Microfluidic component (1, 1′) according to claim 7, characterised in that, viewed in the direction of flow (S) of the liquid (F2), at least one valve (50a) is connected in front of the cavity (30) filled with gas (L) and at least one valve (50b) is connected behind the cavity (30) filled with gas (L). ### Claim 10 (depends on 7) Microfluidic component (1, 1′) according to claim 7, characterised in that the valves (50a, 50b) are actuatable. ### Claim 11 (depends on 7) Microfluidic component (1, 1′) according to claim 7, characterised in that the cavity (20′) to be washed comprises, in the direction of flow (S), a first section (23) in which the cross-section of the cavity (20′) widens out continuously and a second section (25) in which the cross-section of the cavity (20′) tapers continuously. ### Claim 12 (depends on 11) Microfluidic component (1,1′) according to claim 11, characterised in that a section (24) of constant cross-section is arranged between the sections (23 and 25) of varying cross-section. ### Claim 13 (depends on 7) Microfluidic component (1, 1′) according to claim 7, characterised in that the cavity (30) filled with gas (L) is fluidically connectable to at least one further gas reservoir. ### Claim 14 (depends on 13) Microfluidic component (1, 1′) according to claim 13, characterised in that the fluidic connection can be provided by an actuatable valve (70). ### Claim 15 (depends on 7) Microfluidic component (1, 1′) according to claim 7, characterised in that the gas (L) is air.