# US 12,181,386 B2 · Lipid-preserving refractive index matching for prolonged imaging depth for transparent tissue sample and composition > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,181,386 B2 - Document ID: US12181386B2 - Status: Granted - Kind: B2 - Application number: 16/760,652 - Filed: 2018-11-09 - Published: 2021-12-02 - Granted: 2024-12-31 - Earliest claimed: 2017-11-09 - Assignees: Case Western Reserve University; University Hospitals Cleveland Medical Center; Vanderbilt University - Applicants: Case Western Reserve University; University Hospitals Cleveland Medical Center - Inventors: Michael W. Jenkins; Yehe Liu - Web page: https://patentgrep.com/patent/US12181386B2 ## CPC - G01N 1/30: Staining; Impregnating {; Fixation; Dehydration; Multistep processes for preparing samples of tissue, cell or nucleic acid material and the like for analysis} - G01N 33/5082: {Supracellular entities, e.g. tissue, organisms} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) ## Abstract The present disclosure relates to an optical clearing method called lipid-preserving index matching for prolonged imaging depth (LIMPID). The optical clearing method can include simply immersing a sample in an optical clearing solution before imaging (e.g., with microscopy or optical coherence tomography). The optical clearing solution can include water; an iodine-containing non-ionic radiocontrast agent; and urea. ## Claims ### Claim 1 An optical clearing solution for a labeled sample, the optical clearing solution comprising: water; an iodine-containing, non-ionic radiocontrast agent comprising 40 to 80 weight percent iodixanol in solution with 1 to 20 weight percent triethanolamine; 1 to 20 weight percent of iohexol; and urea for lipid preservation, wherein the urea has a concentration of 10 to 50 weight percent, wherein the optical clearing solution is configured to preserve lipids within the labeled sample without reducing diffusion speed through a synergistic combination of at least the iodine-containing, non-ionic radiocontrast agent comprising the 40 to 80 weight percent iodixanol in solution with the 1 to 20 weight percent triethanolamine and the urea having the concentration of 10 to 50 weight percent. ### Claim 2 (depends on 1) The optical clearing solution of claim 1, wherein the 1 to 20 weight percent of the iohexol adjusts a refractive index of the optical clearing solution. ### Claim 3 (depends on 1) The optical clearing solution of claim 1, wherein a refractive index of the optical clearing solution matches a refractive index of optical hardware to eliminate tissue distortion. ### Claim 4 (depends on 1) The optical clearing solution of claim 1, further comprising 0 to 1 weight percent of a detergent to help permeabilization of cells in a tissue. ### Claim 5 (depends on 4) The optical clearing solution of claim 4, wherein the detergent is triton X-100, digitonin or saponin. ### Claim 6 A method comprising: immersing a labeled sample in an optical clearing solution before imaging, wherein the optical clearing solution comprises: water; an iodine-containing, non-ionic radiocontrast agent comprising 40 to 80 weight percent iodixanol in solution with 1 to 20 weight percent triethanolamine; 1 to 20 weight percent of iohexol; and urea to preserve lipids of a labeled sample, wherein the urea has a concentration of 10 to 50 weight percent; and imaging the labeled sample with lipids within the labeled sample preserved without reducing diffusion speed. ### Claim 7 (depends on 6) The method of claim 6, wherein the imaging is fluorescent microscopy, confocal microscopy, light-sheet microscopy, two-photon microscopy, structured illumination microscopy, light-field microscopy, or optical coherence tomography. ### Claim 8 (depends on 6) The method of claim 6, wherein the 1 to 20 weight percent of the iohexol adjusts a refractive index of the optical clearing solution. ### Claim 9 (depends on 6) The method of claim 6, wherein the optical clearing solution matches a refractive index of optical hardware of an imaging modality to eliminate optical distortion. ### Claim 10 (depends on 6) The method of claim 6, wherein optical clearing solution further comprises 0 to 1 weight percent of a detergent to help permeabilization of cells in a tissue. ### Claim 11 (depends on 1) The optical clearing solution of claim 1, further comprising 0 to 20 weight percent of glycerol to adjust an osmolality of the optical clearing solution. ### Claim 12 (depends on 6) The method of claim 6, wherein the optical clearing solution further comprises 0 to 20 weight percent glycerol to adjust an osmolality of the optical clearing solution. ### Claim 13 An optical clearing solution for a labeled sample, the optical clearing solution consisting of: water; an iodine-containing, non-ionic radiocontrast agent comprising 40 to 80 weight percent iodixanol in solution with 1 to 20 weight percent triethanolamine; 1 to 20 weight percent of iohexol; and urea for lipid preservation, wherein the urea has a concentration of 10 to 50 weight percent, wherein the optical clearing solution is configured to preserve lipids within the labeled sample without reducing diffusion speed through a synergistic combination of at least the iodine-containing, non-ionic radiocontrast agent comprising the 40 to 80 weight percent iodixanol in solution with the 1 to 20 weight percent triethanolamine and the urea having the concentration of 10 to 50 weight percent.