Abstract: A well tracking device includes a rectangular frame including four sidewalls. The sidewalls define sets of opposing grooves, and the well tracking device is configured to receive or fit on top of a multi-well plate. The well tracking device also includes a well coordinate indicator positioned on an upper portion of the rectangular frame, that includes labels associated with columns and/or rows of the multi-well plate. The well tracking device also includes at least one slider that is configured to interface with a set of opposing grooves and slide along a width or length of the rectangular frame. The slider includes a plurality of openings disposed along the elongated shape of the slider.

Abstract: The present disclosure relates to the determination of analytes in a sample using chromatography. The present disclosure provides methods of separating an analyte from a sample. A mobile phase is flowed through a chromatography column. The mobile phase includes about 0.005% (v/v) to about 2.50% (v/v) difluoroacetic acid and less than about 100 ppb of any individual impurity, especially metal impurities. A sample including the analyte is injected into the mobile phase. The analyte is separated from the sample.

Abstract: A well tracking device includes a rectangular frame including four sidewalls. The sidewalls define sets of opposing grooves, and the well tracking device is configured to receive or fit on top of a multi-well plate. The well tracking device also includes a well coordinate indicator positioned on an upper portion of the rectangular frame, that includes labels associated with columns and/or rows of the multi-well plate. The well tracking device also includes at least one slider that is configured to interface with a set of opposing grooves and slide along a width or length of the rectangular frame. The slider includes a plurality of openings disposed along the elongated shape of the slider.

Abstract: The present disclosure relates to the determination of analytes in a sample using chromatography. The present disclosure provides methods of separating an analyte from a sample. A mobile phase is flowed through a chromatography column. The mobile phase includes about 0.005% (v/v) to about 2.50% (v/v) difluoroacetic acid and less than about 100 ppb of any individual impurity, especially metal impurities. A sample including the analyte is injected into the mobile phase. The analyte is separated from the sample.