Gas knife using parallelogram flow

Abstract

In one aspect of the present disclosure is a method of contactlessly urging, directly, or moving a substance on the surface of a substrate, the method employing a gas knife configured to produce a gas curtain having parallelogram flow.

1 . A method of moving a fluid present on an upper surface of a slide, comprising:
 (a) positioning a gas knife proximal a first longitudinal edge of a slide, the gas knife providing a substantially uniform gas curtain directed toward the slide, the gas curtain having a gas flow rate of between about 10 L/min to about 20 L/min; and   (b) moving the gas knife across the slide at a velocity of between about 0.75 inches/second and about 1.25 inches/second in a direction substantially perpendicular to the longitudinal axis of the slide, wherein the gas knife maintains a height separation from the upper surface of the slide throughout its movement, the height separation ranging from between about 0.4 cm to about 0.6 cm.   
     
     
         2 . The method of  claim 1 , wherein the gas curtain imparts a gas flow having at least a first component which is parallel to the longitudinal axis of the slide. 
     
     
         3 . The method of  claim 1 , wherein the gas curtain directs the fluid toward at least a wicking feature in communication with the slide. 
     
     
         4 . The method of  claim 1 , wherein the gas knife is moved in a first direction substantially perpendicular to the longitudinal axis of the slide and ends at a position proximal to a second longitudinal edge of the slide. 
     
     
         5 . The method of  claim 4 , wherein the fluid is directed toward the second longitudinal edge and/or toward a second wicking feature at a label end of the slide. 
     
     
         6 . The method of  claim 1 , further comprising the step of moving the gas knife is a second direction originating at a position proximal the second longitudinal edge of the slide and toward the first longitudinal edge of the slide. 
     
     
         7 . The method of  claim 6 , wherein the fluid is directed toward the first longitudinal edge and/or toward a first wicking feature at the label end of the slide. 
     
     
         8 . The method of  claim 1 , wherein the method further comprises positioning a fluid dispenser over an upper surface of the slide and dispensing an additional fluid at least onto a specimen located on the upper surface of the slide. 
     
     
         9 . A gas knife comprising a plenum and a plurality of outlets in fluidic communication with the plenum, the plurality of outlets arranged in parallel along an end of the plenum, each gas outlet having a slant angle relative to a longitudinal axis of the plenum ranging from between about 20 degrees to about 40 degrees, and wherein a ratio between a length of the outlet and a diameter of the outlet is greater than 5. 
     
     
         10 . The gas knife of  claim 9 , wherein the plurality of outlets are provided at a pitch of between about 3 and about 20 outlets per inch. 
     
     
         11 . The gas knife of  claim 9 , wherein the pitch ranges from between about 5 and about outlets per inch. 
     
     
         12 . The gas knife of  claim 9 , wherein the pitch ranges from between about 8 to about 12 outlets per inch. 
     
     
         13 . The gas knife of  claim 9 , wherein the pitch is about 10 outlets per inch. 
     
     
         14 . The gas knife of  claim 9 , wherein the ratio between the length of the outlet and the diameter of the outlet is greater than 7.5. 
     
     
         15 . The gas knife of  claim 9 , wherein the ratio is greater than 10. 
     
     
         16 . The gas knife of  claim 9 , wherein the slant angle of the outlet relative to the longitudinal axis of the plenum ranges from between about 25 degrees to about 30 degrees. 
     
     
         17 . The gas knife of  claim 9 , wherein the slant angle is about 30 degrees. 
     
     
         18 . The gas knife of  claim 9 , wherein the angle of the outlet relative to the longitudinal axis of a plenum is about 30 degrees; wherein the plurality outlets are provided at a pitch of between about 8 and about 12 outlets per inch; and wherein the ratio between the length of the outlet and the diameter of the outlet is greater than 5. 
     
     
         19 . An automated coverslipper comprising a fluid dispenser; and the gas knife of  claim 9 .