A method and system for injecting an unconcentrated sample into a receiving LC/MS/MS system that is configured to determine a concentration of one or more PFAS analytes within the unconcentrated sample, wherein the LC/MS/MS includes ESI. The unconcentrated sample may be subjected to one or more of the following ESI conditions: i) a probe gas temperature of approximately 120° C. to approximately 180° C.; ii) a sheath gas heater setting of approximately 250° C. to approximately 400° C.; and/or iii) a sheath gas flow of approximately 8 L/min to approximately 12 L/min. The unconcentrated sample's concentration and/or an injected amount of the one or more PFAS analytes is determined.

The disclosure relates to a reversed-phase chromatography method for the determination of at least one of glyphosate or AMPA in a sample. The method includes obtaining the sample comprising the at least one of glyphosate or AMPA in a sample matrix and introducing the sample to a reversed-phase chromatography system. The reversed-phase chromatography system includes a reversed-phase column having a stationary phase material contained inside the column. The stationary phase material includes a phenyl functional group. The method also includes flowing the sample with a mobile phase eluent through the reversed-phase column, wherein the at least one of glyphosate or AMPA is substantially resolved and retained. The mobile phase eluent has a pH between about 1.5 to about 2.5. The at least one of glyphosate or AMPA are detected using a detector.

A method of determining total organofluorine in a sample comprising PFAS, comprising: providing a solution of PFAS in an organic solvent to obtain extracted PFAS, or extracting a sample with an organic solvent to obtain extracted PFAS; treating the extracted PFAS with a sodium metal dispersion and alcohol to obtain sodium fluoride; and quantifying the amount of the fluoride. Surprisingly, we discovered that the method recovered substantial fluorine from PFAS and significantly higher yields obtained by selection of the appropriate alcohols. The method is selective for organofluorine from inorganic fluorine.

A method and system for injecting an unconcentrated sample into a receiving LC/MS/MS system that is configured to determine a concentration of one or more PFAS analytes within the unconcentrated sample, wherein the LC/MS/MS includes ESI. The unconcentrated sample is subjected to the following ESI conditions: i) a probe gas temperature of approximately 120° C. to approximately 180° C.; ii) a sheath gas heater setting of approximately 250° C. to approximately 400° C.; and iii) a sheath gas flow of approximately 8 L/min to approximately 12 L/min. The unconcentrated sample's concentration and/or an injected amount of the one or more PFAS analytes is determined.

An ion beam analysis method to quantitatively measure the presence of fluorinated compounds in aqueous samples. The method is a quick, cost effective, nondestructive and quantitative, screen for the presence of fluorinated compounds in solution. The present invention includes a novel method of using an ion beam analysis method (such as PIGE) in air (ex vacuo) to unambiguously easily, quickly, accurately, precisely and cost effectively identify the presence of fluorinated compounds (such as PFASs) that have been extracted from aqueous solutions. The present invention may be used with a wide variety of aqueous solutions, including environmental groundwater samples, with little processing.

The present invention provides a novel method that is capable of detecting a trifluridine-related substance from a sample containing trifluridine or a salt thereof by high-performance liquid chromatography comprising two steps that are performed under gradient conditions. More specifically, the method is for detecting a trifluridine-related substance, the method comprising the step of subjecting a sample containing trifluridine or a salt thereof to high-performance liquid chromatography using a mobile phase composed of an organic phase and an aqueous phase, wherein the step of high-performance liquid chromatography comprises steps 1 and 2 that satisfy the following requirements: Step 1: the percentage of the organic phase in the entire mobile phase is 1 to 14% by volume; and Step 2: after step 1, elution is performed by applying a gradient of increasing the percentage of the organic phase in the entire mobile phase.

The present invention provides a novel method that is capable of detecting a trifluridine-related substance from a sample containing trifluridine or a salt thereof by high-performance liquid chromatography comprising two steps that are performed under gradient conditions. More specifically, the method is for detecting a trifluridine-related substance, the method comprising the step of subjecting a sample containing trifluridine or a salt thereof to high-performance liquid chromatography using a mobile phase composed of an organic phase and an aqueous phase, wherein the step of high-performance liquid chromatography comprises steps 1 and 2 that satisfy the following requirements: Step 1: the percentage of the organic phase in the entire mobile phase is 1 to 14% by volume; and Step 2: after step 1, elution is performed by applying a gradient of increasing the percentage of the organic phase in the entire mobile phase.

The disclosure relates to a reversed-phase chromatography method for the determination of at least one of glyphosate or AMPA in a sample. The method includes obtaining the sample comprising the at least one of glyphosate or AMPA in a sample matrix and introducing the sample to a reversed-phase chromatography system. The reversed-phase chromatography system includes a reversed-phase column having a stationary phase material contained inside the column. The stationary phase material includes a phenyl functional group. The method also includes flowing the sample with a mobile phase eluent through the reversed-phase column, wherein the at least one of glyphosate or AMPA is substantially resolved and retained. The mobile phase eluent has a pH between about 1.5 to about 2.5. The at least one of glyphosate or AMPA are detected using a detector.

A process for separating a component of interest from a gas mixture liquefied sample comprising the steps of (a) subjecting the sample to a preparative reverse-phase high performance liquid chromatography (RP-HPLC); and (b) collecting at least a portion of the component of interest; wherein: (i) the process is performed at a temperature from 10 to 60 C.; and (ii) the gas mixture liquefied sample applied on the HPLC column as well as the components eluting through the HPLC are maintained in liquid form, by applying a pressure equal to or higher than a vapor pressure value P at least during the step (a). Advantageously, the equipment and process allows the efficient separation of liquefied gas mixtures at room temperature.

The present invention provides a novel method that is capable of detecting a trifluridine-related substance from a sample containing trifluridine or a salt thereof by high-performance liquid chromatography comprising two steps that are performed under gradient conditions. More specifically, the method is for detecting a trifluridine-related substance, the method comprising the step of subjecting a sample containing trifluridine or a salt thereof to high-performance liquid chromatography using a mobile phase composed of an organic phase and an aqueous phase, wherein the step of high-performance liquid chromatography comprises steps 1 and 2 that satisfy the following requirements: Step 1: the percentage of the organic phase in the entire mobile phase is 1 to 14% by volume; and Step 2: after step 1, elution is performed by applying a gradient of increasing the percentage of the organic phase in the entire mobile phase.