# US 9,518,960 B2 · System and method for rapid analysis of polycyclic aromatic hydrocarbons > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,960 B2 - Document ID: US9518960B2 - Status: Granted - Kind: B2 - Application number: 14/503,998 - Filed: 2014-10-01 - Published: 2015-04-02 - Granted: 2016-12-13 - Earliest claimed: 2013-10-02 - Assignees: Waters Technologies Corporation - Applicants: Waters Technologies Corporation - Inventors: Tarang Nema; Melvin Gay; Mark Ritchie - Web page: https://patentgrep.com/patent/US9518960B2 ## CPC - G01N 30/06: Preparation - B01J 20/287: Non-polar phases; Reversed phases - B01J 20/288: Polar phases - G01N 30/52: Physical parameters - G01N 30/88: Integrated analysis systems specially adapted therefor, not covered by a single one of the groups G01N30/04 - G01N30/86 - G01N 30/68: Flame ionisation detectors - G01N 30/72: Mass spectrometers {(mass spectrometers per se H01J49/00)} - G01N 30/74: Optical detectors {(measurement of intensity, velocity, spectral content, polarisation, or phase of infrared, visible or ultraviolet light G01J)} - G01N 2030/525: {surface properties, e.g. porosity} - G01N 2030/8854: {involving hydrocarbons} - 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) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS ## Abstract The subject technology is directed to a CO2-based system and method for rapid determination of the levels and/or the presence or absence of polycyclic aromatic hydrocarbons (PAHs). ## Claims ### Claim 1 A method for detecting one or more polycyclic aromatic hydrocarbons (PAHs) in a sample by means of a CO2-based chromatography analysis comprising: providing a sample comprising one or more PAHs for analysis; wherein the sample is prepared with, extracted or dissolved in a diluent comprising at least 60% organic solvent, with the proviso that the sample is analyzed without a solvent exchange step; applying the sample to a chromatography column with a solid stationary phase comprising inorganic or hybrid particles having a mean particle size of about 0.5 to about 3.5 microns, wherein said particles have a non-polar or polar/non-polar surface functionality, and wherein the particles retain said one or more PAHs; eluting the one or more PAHs from the chromatography column by a mobile phase comprising a mixture of liquid CO2 and a modifier to form one or more eluted PAHs; wherein the mobile phase has a pre-column dwell volume of about 75 μL to about 500 μL; and detecting said one or more eluted PAHs. ### Claim 2 (depends on 1) The method of claim 1, wherein the sample is not subject to a derivatization step. ### Claim 3 (depends on 2) The method of claim 2, wherein the organic portion of the hybrid particles comprises substituted or unsubstituted C1-C18 alkylene, alkenylene, alkynylene or arylene moiety bridging two or more atoms of the inorganic portion. ### Claim 4 (depends on 1) The method of claim 1, wherein the particles having a non-polar surface functionality comprise capped particles with non-polar surface modifiers comprising an alkyl group, alkenyl group, alkynyl group, aryl group, an alkyl or aryl group containing one or more embedded non-polar functionalities, or a mixture thereof. ### Claim 5 (depends on 1) The method of claim 1, wherein the particles having a polar/non-polar surface functionality comprise uncapped particles with free surface hydroxyl groups and non-polar surface modifiers comprising an alkyl group, alkenyl group, alkynyl group, aryl group, an alkyl or aryl group containing one or more embedded non-polar functionalities, or a mixture thereof. ### Claim 6 (depends on 1) The method of claim 1, wherein the particles have a mean particle size of about 0.5 to about 2 microns. ### Claim 7 (depends on 1) The method of claim 1, wherein the particles have a mean pore volume in the range of about 0.1 to about 2.5 cm/g. ### Claim 8 (depends on 1) The method of claim 1, wherein the particles have a mean pore diameter in the range of about 100 to about 1000 Angstroms. ### Claim 9 (depends on 1) The method of claim 1, wherein the inorganic particles comprise aluminum, titanium, cerium, zirconium, barium, cobalt, copper, europium, gadolinium, iron, nickel, samarium, silver, titanium, diamond, zinc, boron or oxides thereof, silicon carbide, carbon black, carbon nanotubes, ceramic, glass, metallic materials or mixtures thereof. ### Claim 10 (depends on 1) The method of claim 1, wherein the hybrid particles comprise an inorganic portion and an organic portion. ### Claim 11 (depends on 10) The method of claim 10, wherein the inorganic portion of the hybrid particles comprises silicone, aluminum, titanium, cerium, zirconium, barium, cobalt, copper, europium, gadolinium, iron, nickel, samarium, silver, titanium, diamond, zinc, boron or oxides thereof, silicon carbide, carbon black, carbon nanotubes, ceramic, glass, metallic materials or mixtures thereof. ### Claim 12 (depends on 10) The method of claim 10, wherein the organic portion of the hybrid particles comprises substituted or unsubstituted C1-C18 alkane, alkylene, alkenylene, alkynylene or arylene moiety bonded to one or more atoms of the inorganic portion. ### Claim 13 (depends on 1) The method of claim 1, wherein the chromatography column is kept in a temperature range of about 5° C. to about 85° C. ### Claim 14 (depends on 1) The method of claim 1, wherein the mobile phase further comprises a modifier added to the liquid CO2 in a constant or gradient mode or both over an elution period or a fraction thereof. ### Claim 15 (depends on 14) The method of claim 14, wherein the modifier is a polar water-miscible organic solvent selected from the group consisting of methanol, ethanol or isopropanol, acetonitrile, acetone, tetrahydrofuran, mixtures thereof, and mixtures of water and any of these solvents. ### Claim 16 (depends on 14) The method of claim 14, wherein the gradient mode comprises increasing or decreasing flow volume of the modifier. ### Claim 17 (depends on 14) The method of claim 14, wherein the elution period is about 5 minutes. ### Claim 18 (depends on 14) The method of claim 14, wherein the gradient mode comprises increasing the flow volume of the modifier from about 0% to about 50% (v/v CO2) or any intervals therebetween. ### Claim 19 (depends on 14) The method of claim 14, wherein the gradient mode comprises increasing the flow volume of the modifier from about 0% to about 25% (v/v CO2). ### Claim 20 (depends on 1) The method of claim 1, wherein the liquid CO2 is in a supercritical state or a subcritical state or both. ### Claim 21 (depends on 1) The method of claim 1, wherein the detection comprises determining the levels or the presence or absence of the one or more PAHs. ### Claim 22 (depends on 1) The method of claim 1, wherein the detection is by way of a mass spectrometer; Evaporative Light Scattering (ELS) detector, Circular Dichroism (CD) detector, Flame Ionization Detector (FID) or a photodiode array detector (PDA). ### Claim 23 (depends on 1) The method of claim 1, wherein the sample comprises an environmental sample, chemical sample, food sample, biological sample, or an extract thereof. ### Claim 24 (depends on 1) The method of claim 1, wherein the chromatography column is part of a chromatography system comprising a pre-column mobile phase dwell volume of about 100 to about 500 μL; wherein said pre-column mobile phase dwell volume is the volume of the mobile phase present in a fluidic connection between a junction at which the CO2 and the modifier are mixed and the head of the chromatography column. ### Claim 25 (depends on 1) The method of claim 1, wherein the one or more PAHs are eluted from the chromatography column by the mobile phase with a flow rate of about 1 to 4 mL/min. ### Claim 26 (depends on 1) The method of claim 1, wherein the chromatography column has a length of about 50 to 150 mm and an internal diameter about 2 to 4 mm. ### Claim 27 A chromatography method for detecting one or more polycyclic aromatic hydrocarbons (PAHs) in a sample comprising the steps of: providing a sample comprising one or more PAHs for analysis; wherein the sample is prepared with, extracted or dissolved in a diluent comprising at least 60% organic solvent, with the proviso that the sample is analyzed without a solvent exchange step; applying the sample to a chromatography column with a solid stationary phase comprising inorganic or hybrid particles having a mean particle size of about 0.5 to about 3.5 microns, wherein said particles have a polar surface functionality, and wherein the particles retain said one or more PAHs; eluting the one or more PAHs from the chromatography column by a mobile phase comprising a liquid CO2 to form one or more eluted PAHs, wherein the mobile phase has a pre-column dwell volume of about 75 μL to about 500 μL; and detecting said one or more eluted PAHs by a mass spectrometer. ### Claim 28 A method for detecting one or more PAHs comprising: (1) providing a sample comprising one or more PAHs for analysis; wherein the sample is prepared with, extracted or dissolved in a diluent comprising at least 60% organic solvent, with the proviso that the sample is not subject to a solvent exchange step; (2) applying the sample to a chromatography system comprising: (a) a column with a solid stationary phase comprising an inorganic or hybrid particle having a mean particle size of about 0.5 to about 3.5 microns, wherein said particle has a non-polar or polar/non-polar surface functionality, wherein said column has a length of about 50 to 150 mm and an internal diameter about 2 to 4 mm, and wherein the solid stationary phase retains said one or more PAHs; (b) a pre-column mobile phase dwell volume of about 75 μL to about 500 μL; wherein said pre-column dwell volume comprises a space within a fluidic connection between a junction at which the CO2 and the modifier are mixed to the head of the column; and (c) a post-column mobile phase dwell volume of about 10 μL to about 450 μL; wherein said post-column dwell volume comprises a space within a fluidic connection between the end of the column and a detector; (3) eluting the one or more PAHs from the chromatography column by a mobile phase comprising a mixture of CO2 and a modifier to form one or more eluted PAHs, wherein the mobile phase has a flow rate of about 1 to 4 mL/min; and (4) detecting said one or more eluted PAHs. ### Claim 29 A kit for performing analysis or detecting one or more PAHs in a sample comprising: a sample preparation device for preparing the sample comprising one or more PAHs for analysis; wherein the sample is prepared with, extracted or dissolved in a diluent comprising at least about 60% organic solvent, with the proviso that the sample is analyzed without a solvent exchange step; a chromatography column with a solid stationary phase comprising inorganic or hybrid particles having a mean particle size of 0.5 to 3.5 microns; wherein said particles have a non-polar or polar/non-polar surface functionality and retain said one or more PAHs; and one or more standards for calibrating, and facilitating the analysis and detection of the one or more PAHs.