US 12,449,363 B2
Fluorescence-detected mid-infrared photothermal microscopy
Garth Jason Simpson, West Lafayette, IN (US); Aleksandr Razumtcev, West Lafayette, IN (US); and Minghe Li, West Lafayette, IN (US)
Assigned to PURDUE RESEARCH FOUNDATION
Appl. No. 18/286,320
Filed by PURDUE RESEARCH FOUNDATION, West Lafayette, IN (US)
PCT Filed Apr. 12, 2022, PCT No. PCT/US2022/024439
§ 371(c)(1), (2) Date Oct. 10, 2023,
PCT Pub. No. WO2022/221290, PCT Pub. Date Oct. 20, 2022.
Claims priority of provisional application 63/173,500, filed on Apr. 12, 2021.
Prior Publication US 2024/0328949 A1, Oct. 3, 2024
Int. Cl. G01N 21/64 (2006.01); G01N 21/35 (2014.01); G01N 21/63 (2006.01); G01N 21/17 (2006.01)
CPC G01N 21/6458 (2013.01) [G01N 21/35 (2013.01); G01N 21/636 (2013.01); G01N 2021/1731 (2013.01); G01N 2021/3595 (2013.01); G01N 2021/6439 (2013.01); G01N 2201/06113 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A method of selectively photothermally heating a sample in a fluorescence-detected mid-infrared photothermal microscopy in order to discriminate between two components in the sample, comprising:
energizing a sample with one or more modulated infrared (IR) beams sourced by a multichannel laser array;
concurrently continuously illuminating the sample with a probe beam, thereby generating a fluorescence response signal, whereby the multichannel laser output is modulated thereby modulating the heating at a predetermined frequency, thereby modulating the fluorescence response signal;
capturing the fluorescence response signal;
processing the captured modulated fluorescence response signal into two IR absorption spectra corresponding to chemical properties of two components in the sample by scanning over each channel of the multichannel laser array;
generating a binary mask associated with the two spectra;
establishing a cost function based on the generated binary mask;
optimizing the cost function by optimizing the binary mask; and
selectively energizing channels of the multichannel laser array based on the optimized binary mask thereby maximizing discrimination between the two components.