US 12,146,836 B2
Method and apparatus for continuous gas monitoring using micro-colorimetric sensing and optical tracking of color spatial distribution
Nongjian Tao, Fountain Hills, AZ (US); Di Wang, Tempe, AZ (US); and Chenwen Lin, Tempe, AZ (US)
Assigned to Arizona Board of Regents on behalf of Arizona State University, Scottsdale, AZ (US)
Filed by Arizona Board of Regents on behalf of Arizona State University, Scottsdale, AZ (US)
Filed on Feb. 25, 2022, as Appl. No. 17/681,128.
Application 17/681,128 is a division of application No. 16/142,463, filed on Sep. 26, 2018, granted, now 11,293,875.
Claims priority of provisional application 62/564,143, filed on Sep. 27, 2017.
Prior Publication US 2022/0178834 A1, Jun. 9, 2022
Int. Cl. G01N 21/78 (2006.01); G01N 21/77 (2006.01); G01N 33/00 (2006.01)
CPC G01N 21/783 (2013.01) [G01N 33/0037 (2013.01); G01N 33/0039 (2013.01); G01N 33/0047 (2013.01); G01N 2021/7763 (2013.01); G01N 2021/7793 (2013.01); G01N 2201/0621 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method for making a micro-colorimetric sensor, the method comprising:
providing a substrate having a substrate top surface;
entrenching a plurality of parallel linear channels containing porous media into the substrate, wherein each parallel linear channel of the plurality parallel linear channels comprises an inlet end and an outlet end;
embedding a selected one of a plurality of sensing materials into each of the plurality of parallel linear channels, wherein each sensing material of the plurality of sensing materials is adapted to sense one of several specific target chemicals in air;
separating each parallel linear channel of the plurality of parallel linear channels from adjacent parallel linear channels with a barrier material that blocks diffusion of chemicals between each parallel linear channel of the plurality of parallel linear channels;
providing a means to determine spatial distribution of color generated from a chemical reaction of analytes with the plurality of sensing materials embedded into each linear channel of the plurality of linear channels; and
affixing a plate over the substrate top surface to cover the plurality of parallel linear channels so as to form a micro-colorimetric sensor.