Apparatuses and methods for modulating fluids using acoustically oscillating solid structures

Abstract

An acoustofluidic apparatus is provided that functions by the generation of microstreaming in fluid produced by the oscillation of oscillatory elements excited by an energy input such as acoustic energy. An acoustofluidic apparatus includes an oscillatory energy field generator in energetic contact with one or more oscillatory elements contained in a fluid passage. Oscillation of the oscillatory elements induces microstreaming in a fluid that can be used to mix laminar flows of differing fluids, as a micropump for the directional movement of fluid through a fluid passage, for the generation of waveforms in a fluid or plurality of fluids or for other purposes.

1 . An acoustofluidic apparatus comprising:
 a fluid passage, said fluid passage comprising at least one sidewall, at least one inlet, and at least one outlet;   an oscillatory element comprising a tip extending into said fluid passage; and   an acoustic source in acoustic contact with said oscillatory element, said acoustic source operable to vibrate said oscillatory element or a portion thereof, so as to create microstreaming in a fluid within said fluid passage.   
     
     
         2 . The acoustofluidic apparatus of  claim 1 , said oscillatory element comprising two adjacent surfaces extending between said sidewall and said tip, said adjacent surfaces being disposed at a tip angle with respect to each other, the tip angle being less than 180 degrees. 
     
     
         3 . The acoustofluidic apparatus of  claim 2 , wherein the tip angle is less than or equal to 45 degrees. 
     
     
         4 . The acoustofluidic apparatus of  claim 1 , said tip having a surface with a width and a length. 
     
     
         5 . The acoustofluidic apparatus of  claim 4 , said length equal to the height of said fluid channel. 
     
     
         6 . The acoustofluidic apparatus of  claim 4 , said width is from 5 to 100 micrometers. 
     
     
         7 . The acoustofluidic apparatus of  claim 1 , said oscillatory element extending at a tilting angle relative to the length of said sidewall, said tilting angle being 90 degrees or less. 
     
     
         8 . The acoustofluidic apparatus of  claim 7 , said tilting angle is from 0 degrees to 70 degrees. 
     
     
         9 . The acoustofluidic apparatus of  claim 1 , wherein the acoustic source is a piezoelectric transducer. 
     
     
         10 . The acoustofluidic apparatus of  claim 1 , wherein the acoustic source is operable to vibrate the oscillatory element at a frequency in the range of 2 Hz to 900 MHz. 
     
     
         11 . A process of inducing microstreaming in a fluid comprising:
 contacting a first fluid in a fluid passage with a oscillatory element; and   acoustically oscillating said oscillatory element with an acoustic source in acoustic contact with said oscillatory element so as to induce microstreaming in said first fluid.   
     
     
         12 . The process of  claim 11  wherein said oscillatory element comprises a tip angle of 45 degrees or less. 
     
     
         13 . The process of  claim 11  wherein said oscillatory element is oriented relative to an edge of said fluid passage by a tilting angle from 0 degrees to 70 degrees. 
     
     
         14 . The process of  claim 11  wherein said oscillatory element oscillates at a frequency in the range of 2 Hz to 900 MHz. 
     
     
         15 . The process of  claim 11  wherein said microstreaming induces mixing of said first fluid and a second fluid, and optionally a third fluid, within said fluid channel. 
     
     
         16 . The process of  claim 15  producing a concentration gradient of a component of said first fluid, said second fluid, optionally said third fluid, or any combination thereof. 
     
     
         17 . The process of  claim 15  further comprising contacting said first fluid and said second fluid with a plurality of oscillatory elements off set and generating a gradient profile between said first fluid and said second fluid, and optionally said third fluid. 
     
     
         18 . The process of  claim 15  further comprising alternating said acoustic source from an on state to an off state to produce a temporal gradient waveform of concentration of said first fluid and said second fluid. 
     
     
         19 . A process of pumping fluid through a channel comprising:
 contacting a fluid in a fluid passage with an oscillatory element, said oscillatory element, or oscillating portion thereof, oriented relative to an edge of said fluid passage by a tilting angle from 0 degrees to 180 degrees; and   acoustically oscillating said oscillatory element with an acoustic source in acoustic contact with said oscillatory element so as to induce directional microstreaming in said fluid.   
     
     
         20 . The process of  claim 19  wherein said tilting angle is from 0 degrees to 70 degrees.