# US 11,994,453 B2 · Chelator based eluents for solid phase extraction of phosphorylated compounds > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,994,453 B2 - Document ID: US11994453B2 - Status: Granted - Kind: B2 - Application number: 17/112,408 - Filed: 2020-12-04 - Published: 2021-06-10 - Granted: 2024-05-28 - Earliest claimed: 2019-12-05 - Assignees: Waters Technologies Corporation - Applicants: Waters Technologies Corporation - Inventors: Xiaoxiao Liu; Matthew Lauber; Michael Donegan - Web page: https://patentgrep.com/patent/US11994453B2 ## CPC - G01N 1/405: {by adsorption or absorption} - B01D 15/426: {Specific type of solvent} - B01J 20/28052: {Several layers of identical or different sorbents stacked in a housing, e.g. in a column} - B01J 20/281: Sorbents specially adapted for preparative, analytical or investigative chromatography - B01J 20/3475: {in the liquid phase} - G01N 30/06: Preparation - G01N 30/16: Injection (G01N30/24 takes precedence) - B01J 2220/54: Sorbents specially adapted for analytical or investigative chromatography - G01N 2030/009: {Extraction} - G01N 2030/067: {by reaction, e.g. derivatising the sample} - 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) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS ## Abstract The present technology relates to a method for improved recovery of phosphorylated compounds (e.g., phosphorylated glycans). In particular, the present technology utilizes certain chelator additives in a solution to wash and elute the phosphorylated compounds from a solid phase extraction cartridge. ## Claims ### Claim 1 A method of performing solid phase extraction comprising: injecting a sample comprising glycans into a solid phase extraction cartridge comprising a stationary phase, wherein the glycans are retained by the stationary phase; and washing the solid phase extraction cartridge with a divalent or higher valency carboxylic acid at a concentration of between about 1 mM to about 100 mM to elute the glycans from the solid phase extraction cartridge. ### Claim 2 A method of performing solid phase extraction comprising: injecting a sample comprising glycans into a solid phase extraction cartridge comprising a stationary phase, wherein the glycans are retained by the stationary phase; and washing the solid phase extraction cartridge with a citric acid at a concentration of between about 1 mM to about 100 mM to elute the glycans from the solid phase extraction cartridge. ### Claim 3 (depends on 2) The method of claim 2, wherein the concentration is between about 40 mM and 60 mM to elute the glycans from the solid phase extraction cartridge. ### Claim 4 A method of performing solid phase extraction comprising: injecting a sample comprising glycans into a solid phase extraction cartridge comprising a stationary phase, wherein the glycans are retained by the stationary phase; and washing the solid phase extraction cartridge with an eluent solution to elute the glycans from the solid phase extraction cartridge, wherein the eluent solution comprises (i) a salt to adjust ionic strength of the eluent solution and (ii) a divalent or higher valency carboxylic acid at a concentration of between about 1 mM to about 100 mM. ### Claim 5 (depends on 4) The method of claim 4, where the salt is selected from the group consisting of ammonium formate, ammonium acetate, sodium formate, sodium acetate, ammonium chloride, sodium chloride, potassium chloride, triethylammonium acetate, and tetramethyl ammonium acetate. ### Claim 6 (depends on 5) The method of claim 5, where the solution is prepared with a co-solvent selected from the group consisting of acetonitrile, methanol, ethanol, propanol, butanol, tetrahydrofuran, and isopropanol. ### Claim 7 A method of performing solid phase extraction comprising: injecting a sample comprising glycans into a solid phase extraction cartridge comprising a stationary phase, wherein the glycans are retained by the stationary phase; and washing the solid phase extraction cartridge with an eluent solution to elute the glycans from the solid phase extraction cartridge, wherein the eluent solution comprises (i) a salt to adjust ionic strength of the eluent solution and (ii) citric acid at a concentration of between about 1 mM to about 100 mM. ### Claim 8 (depends on 7) The method of claim 7, where the salt is selected from the group consisting of ammonium formate, ammonium acetate, sodium formate, sodium acetate, ammonium chloride, sodium chloride, potassium chloride, triethylammonium acetate, and tetramethyl ammonium acetate. ### Claim 9 (depends on 8) The method of claim 8, where the solution is prepared with a co-solvent selected from the group consisting of acetonitrile, methanol, ethanol, propanol, butanol, tetrahydrofuran, and isopropanol. ### Claim 10 (depends on 7) The method of claim 7, wherein the concentration is between about 40 mM and 60 mM.