# US 11,906,491 B2 · Peptide markers for authenticating Ejiao and related gelatins > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,906,491 B2 - Document ID: US11906491B2 - Status: Granted - Kind: B2 - Application number: 17/443,963 - Filed: 2021-07-29 - Published: 2022-02-10 - Granted: 2024-02-20 - Earliest claimed: 2020-08-04 - Assignees: Hong Kong Baptist University - Applicants: Hong Kong Baptist University - Inventors: Quanbin Han; Wenjie Wu; Lifeng Li - Web page: https://patentgrep.com/patent/US11906491B2 ## CPC - G01N 30/72: Mass spectrometers {(mass spectrometers per se H01J49/00)} - G01N 33/6848: {Methods of protein analysis involving mass spectrometry} - G01N 30/88: Integrated analysis systems specially adapted therefor, not covered by a single one of the groups G01N30/04 - G01N30/86 - G01N 33/68: involving proteins, peptides or amino acids {(involving lipoproteins G01N33/92)} - G01N 2030/027: {Liquid chromatography} - G01N 2030/8831: {involving peptides or proteins} - 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 Provided herein is a method for authenticating animal hide gelatins using peptide markers found animal hide gelatin hydrolysates. The method can be used to authenticate animal hide gelatins derived from donkey hide, horse hide, pig hide, and cattle hide. ## Claims ### Claim 1 A method of identifying an animal hide gelatin in a sample, the method comprising: providing a hydrolysate of the sample; analyzing the hydrolysate of the sample using a mass spectroscopy method; and detecting one or more peptide markers, wherein a donkey hide gelatin is identified when the one or more peptide markers have an observed mass to charge ratio (m/z) selected from the group consisting of: 518.2695±0.1 (DM1), 675.6632±0.1 (DM2), 761.3672±0.1 (DM3), 766.6952±0.1 (DM4), 774.0218±0.1 (DM5), 784.3392±0.1 (DM6), and 854.0603±0.1 (DM7); or a pig hide gelatin is present when two or more peptide markers have an observed mass to charge ratio (m/z) selected from the group consisting of: 419.2446±0.1 (PM1), 490.5942±0.1 (PM2), 693.8432±0.1 (PM3), 713.6902±0.1 (PM4), 773.9237±0.1 (PM5), and 774.9121±0.2 (PM6). ### Claim 2 (depends on 1) The method of claim 1 further comprising hydrolyzing the sample thereby forming the hydrolysate of the sample. ### Claim 3 (depends on 1) The method of claim 1 further comprising hydrolyzing the sample using a protease thereby forming the hydrolysate of the sample. ### Claim 4 (depends on 1) The method of claim 1 further comprising hydrolyzing the sample using a protease selected from the group consisting of trypsin, chymotrypsin, lysine protease, aspartic protease, pepsin, papain, proteinase K, calpain, and subtilisin thereby forming the hydrolysate of the sample. ### Claim 5 (depends on 1) The method of claim 1 further comprising hydrolyzing the sample using trypsin thereby forming the hydrolysate of the sample. ### Claim 6 (depends on 1) The method of claim 1, wherein the mass spectrometry method is tandem mass spectroscopy (MS/MS) and further comprises liquid chromatography. ### Claim 7 (depends on 1) The method of claim 1, wherein the mass spectrometry method comprises high-performance liquid chromatography (HPLC-MS/MS) or ultra-performance liquid chromatography (UPLC-MS/MS). ### Claim 8 (depends on 6) The method of claim 6, wherein the step of detecting the one or more peptide markers further comprises detecting that each of the one or more peptide markers has a predicted liquid chromatography retention time, wherein the predicted liquid chromatography retention time of each of the one or more peptide markers is determined by measuring a retention time of one or more standard samples, wherein each of the one or more standard samples comprises a standard specific to one of the one or more peptide markers. ### Claim 9 (depends on 1) The method of claim 1, wherein the step of detecting the one or more peptide markers comprises detecting 2 to 7 peptide markers selected from the group consisting of DM1, DM2, DM3, DM4, DM5, DM6, and DM7. ### Claim 10 (depends on 1) The method of claim 1, wherein the mass spectrometry method is MS/MS and further comprises an ultra-performance liquid chromatography method; and the step of detecting the one or more peptide markers further comprises detecting that each of the one or more peptide markers has a predicted ultra-performance liquid chromatography retention time, wherein the ultra-performance predicted liquid chromatography retention time of each of the one or more peptide markers is determined by measuring as retention time of one or more standard samples, wherein each of the one or more standard samples comprises a standard specific to one of the one or more peptide markers. ### Claim 11 (depends on 1) The method of claim 1, wherein the step of detecting comprises detecting the one or more peptide markers having an observed m/z are DM1, DM2, DM3, DM4, DM5, DM6, and DM7. ### Claim 12 (depends on 11) The method of claim 11 further comprising: hydrolyzing the sample using trypsin thereby forming the hydrolysate of the sample; and the mass spectrometry method is MS/MS and further comprises ultra-performance liquid chromatography. ### Claim 13 (depends on 1) The method of claim 1 further comprising detecting one or more additional peptide markers, wherein the one or more additional peptide markers have an observed mass to charge ratio (m/z) selected from the group consisting of: 386.2108±0.1 (HM1) indicating the presence of horse hide gelatin and 766.8957±0.1 (CM3) indicating the presence of cattle hide gelatin.