Abstract: A permeative amine/acid introduction device (PAID) is placed after a conventional KOH eluent suppressed conductometric anion chromatography (SCAC) system. The PAID converts the suppressed eluites from the acid form to the corresponding salt. For example, when the analytes are acids, they are converted to the corresponding ammonium salt (NR2H+HX?NR2H2++X?) and allows very weak acids HX (pKa?7.0) that cannot normally be detected by SCAC to be measured by a second conductivity detector following the PAID. Permeative reagent introduction is dilutionless, can be operated without pumps and provides good mixing with low band dispersion (as small as 30 ?L). An exemplary amine is diethylamine (DEA), which was chosen as the amine source due to its low pKb value (pKb 3.0), high vapor pressure, and low toxicity and low odor.

Abstract: A method of converting longer path cell signal data to shorter path cell signal data comprising: obtaining a longer path absorbance signal tracing and a shorter path absorbance signal tracing for at least one analyte band under the same conditions; obtaining an approximate superimposable match between the longer path absorbance signal tracing and the shorter path absorbance signal tracing using an amplitude scaling factor and one or more parameters derived from a dispersion model that accounts for dispersion differences between a short cell and a long cell; and applying the dispersion model in reverse using the derived parameters to future longer path absorbance signal traces from the longer path cell signal data to generate the shorter path cell signal data.

Abstract: There is provided a system for performing a chromatographic separation of an analyte, methods of using the system to separate at least one component of an analyte and an eluent generator of use in the system. An exemplary system comprises: (a) an eluent generator comprising: (i) a housing configured to be pressurizable by gas, comprising an annular void defined by the housing, and a gas inlet for the gas and a gas outlet for the gas in fluid communication with the annular void; (ii) a membrane permeable to the gas defining an eluent flow channel disposed within the annular void, the eluent flow channel having an eluent precursor fluid inlet and an eluent outlet; (iii) a source of gas in fluidic communication with the gas inlet; (iv) a source of the eluent precursor fluid; and (b) a chromatography column disposed downstream of and in fluidic communication with the eluent outlet.

Abstract: There is provided a system for performing a chromatographic separation of an analyte, methods of using the system to separate at least one component of an analyte and an eluent generator of use in the system. An exemplary system comprises: (a) an eluent generator comprising: (i) a housing configured to be pressurizable by gas, comprising an annular void defined by the housing, and a gas inlet for the gas and a gas outlet for the gas in fluid communication with the annular void; (ii) a membrane permeable to the gas defining an eluent flow channel disposed within the annular void, the eluent flow channel having an eluent precursor fluid inlet and an eluent outlet; (iii) a source of gas in fluidic communication with the gas inlet; (iv) a source of the eluent precursor fluid; and (b) a chromatography column disposed downstream of and in fluidic communication with the eluent outlet.

Abstract: A permeative amine/acid introduction device (PAID) is placed after a conventional KOH eluent suppressed conductometric anion chromatography (SCAC) system. The PAID converts the suppressed eluites from the acid form to the corresponding salt. For example, when the analytes are acids, they are converted to the corresponding ammonium salt (NR2H+HX?NR2H2++X?) and allows very weak acids HX (pKa?7.0) that cannot normally be detected by SCAC to be measured by a second conductivity detector following the PAID. Permeative reagent introduction is dilutionless, can be operated without pumps and provides good mixing with low band dispersion (as small as 30 ?L). An exemplary amine is diethylamine (DEA), which was chosen as the amine source due to its low pKb value (pKb 3.0), high vapor pressure, and low toxicity and low odor.