Abstract: An improved liquid/liquid solvent extraction method and apparatus utilizes an external electrode for creating an electric field within an extraction cell to shatter aqueous sample droplets flowing within a non-conductive solvent. The external electrode is in intimate contact with the exterior surface of the insulative cell wall so as to preclude direct electrical contact between the electrode and the internal liquids. A sample interface detector permits the interface between the two liquids to be detected when the liquids sequentially flow out from the cell, thereby facilitating separate collection of the liquid. Interface detection is achieved by coupling electrical pulses into the flowing liquid to cause ionization charge/discharge cycles in the conductive aqueous sample but not in the non-conductive solvent. Downstream detection of the charge/discharge cycle in the liquid identifies the interface.

Abstract: Automated gel permeation chromatography of multiple individual samples is effected with high precision and high speed utilizing a common sample sizing loop into which each sample is placed prior to its injection into the chromatography column, thereby eliminating the need for precisely matched sample loops. Each sample is pre-stored in its own container, the containers being automatically sequentially accessed to feed a portion of the contained sample medium to the common sample sizing loop. The common sample flow path, including the sample sizing loop, is automatically cleaned with rinse solvent between loading of successive samples into the sizing loop. Multiple programs may be employed to control the processing times for different types of sample fluid. A sample container closure member having a unique sealing insert member is provided to preclude leakage of fluid from the sample storage container when the container is pressurized.

Abstract: Automated gel permeation chromatography of multiple individual samples is effected with high precision and high speed utilizing a common sample sizing loop into which each sample is placed prior to its injection into the chromatography column, thereby eliminating the need for precisely matched sample loops. Each sample is pre-stored in its own container, the containers being automatically sequentially accessed to feed a portion of the contained sample medium to the common sample sizing loop. The common sample flow path, including the sample sizing loop is automatically cleaned with rinse solvent between loading of successive samples into the sizing loop. Multiple programs may be employed to control the processing times for different types of sample fluid. A sample container closure member having a unique sealing insert member is provided to preclude leakage of fluid from the sample storage container when the container is pressurized.