Abstract: An apparatus is provided for concentrating a solute sample which can be subsequently released for analysis by capillary electrophoresis. The apparatus comprises a tube containing a short length of packed particles or gel adapted to retain sample solutes which particles are retained in the tube by tube constrictions or porous plugs. The tube includes an inlet for introducing a sample into the tube and an outlet for introducing the retained sample into a capillary electrophoresis tube.

Abstract: A device is provided comprising a piezoelectric material and at least one coating reactive with trace quantities of oxygen and/or water in reactive and inert gases. The piezoelectric material is bonded to a conductor for delivering an alternating electric current and to a conductor for transmitting resonant vibration frequency of the crystal. The reactive coating has an effective thickness which provides a serviceable life for the coating while not being so thick as to prevent vibration of the piezoelectric material.

Abstract: A sterility testing device includes a container made up of upper and lower plastic parts between which is welded a hydrophilic microporous membrane filter. The device also includes a removable plastic lid with vent holes. The lid is adapted to be secured to the container in two different positions such that, during in-situ incubation of a culture medium after the filtration of the sample and rinsing, the lid is deformed to allow a passageway for excess pressurized air to be removed from the interior of the container while at the same time preventing ambient air from entering the container. The device thus operates with a single membrane filter and is more economical to manufacture than prior art devices.

Abstract: A macroreticulate polymer is provided for removing water vapor and oxidants from a gas having the formula: ##STR1## wherein Ar is a heteroaromatic moiety, M is bonded to the heteroaromatic moiety and is selected from the group consisting of lithium, sodium, potassium, alkyl magnesium, alkyl zinc, and dialkylaluminum, R is an organic moiety and R.sub.1 is a polymerized moiety forming the molecular backbone of said polymer.

Abstract: A dialysis apparatus is provided including a multiwell plate, a separations membrane and a template having holes which mate with the wells. The membrane is sealed to one end of the wells by positioning the template about the outer peripheral surfaces of the wells with the membrane being frictionally held therebetween.

Abstract: A laminated plate structure including conduit and regent delivery means for a fluid delivery system is provided to deliver precise volumes of a plurality of fluids in sequence to a treatment reservoir. Fluid channels are formed in the plate structure to provide a means for delivering fluids from a plurality of fluid reservoirs attached to the plate structure to one or a plurality of treatment reservoirs attached to the plate structure. Each fluid is delivered by a system comprising a fluid reservoir, an inlet valve in fluid communication with the fluid reservoir, a positive displacement pump in fluid communication with the inlet valve and an outlet valve in fluid communication with the positive displacement pump all of which are attached to the plate structure. The means for delivering fluid and the fluid reservoirs are positioned on opposing surfaces of the plate structure. The plate structure is provided with vent holes for venting vapors that may be produced during formation of the plate structure.

Abstract: A fluid delivery system is provided to deliver precise volumes of a plurality of fluid in sequence to one or more treatment reservoirs. Fluid channels are formed in a plate structure to provide a means for delivering fluids from a plurality of fluid reservoirs to one or a plurality of treatment reservoirs. Each fluid is delivered by a system comprising a pneumatically or electrically activated inlet valve in fluid communication with a fluid reservoir, a positive displacement pump in fluid communication with the inlet valve and a pneumatically or electrically activated outlet valve in fluid communication with the positive displacement pump.

Abstract: A sample collection and analysis apparatus is provided comprising a base and a sample collector having a handle and a well. The well contains a porous member having a ligand receptor bound thereto. The base contains an absorbent material for liquids and an opening to expose the absorbent material. The base is provided with means for rendering the sample collector integral with the base and for contacting the porous member with the absorbent material. The apparatus permits detecting or quantitating a target ligand in the sample.

Abstract: A system for forming a time modulated electrospray from a sample solution is provided. Further systems for analyzing this time modulated electrospray are provided. In a preferred such further system, a grid connected to a time modulated voltage source is provided between an electrospray apparatus and an analytical apparatus. More generally, a system for changing the energy of charged particles in a gas comprising the application of time modulated electric fields is provided.

Abstract: A housing is provided for converting an electrospray into a desolvated ion stream for analysis. The housing is positioned between an electrospray device and an ion stream analytical device. The housing is heated and includes a passageway within which a moving electrospray is converted to the ion stream.

Abstract: An apparatus for the microbiological testing of pressurized liquids is disclosed which includes a completely closed container, at the base of which a membrane filter is sealed. Fitted upstream from the membrane is a built-in reading window and included downstream from the membrane, is a flange comprising a lip seal and a female threaded part. The apparatus may be used in conjunction with a microbiological testing process by screwing to the container a filtration support, taking and filtering the sample to be analyzed, and then substituting for the support an incubation cartridge for the subsequent development, in an incubator, of the colonies collected on the membrane.

Abstract: A method for performing capillary electrophoresis with improved regularity of migration time of the analytes is disclosed. A capillary electrophoresis system includes a fused silica capillary, a high voltage power supply, electrolyte reservoirs at both ends of the capillary, means for injecting a sample, and a detector. After separation, analytes within the sample are identified by comparing their migration time with the migration time of internal or external standards. Since migration times are dependent on the concentration of the injected sample, identification of unknown analytes can often be difficult or subject to error without the use of such standards. These problems associated with concentration dependent migration time are substantially eliminated by using a combination of high voltage power supply running modes (i.e. constant current, constant voltage or constant power) during the course of the analysis.

Abstract: A composite porous membrane is formed from a porous polymeric substrate having its entire surface modified with a cross-linked polymer which results in a hydrophobic and oleophobic surface. The composite membrane retains substantially all of its other original properties. The cross-linked polymer is formed in situ on the polymeric substrate from a reactant system comprising an ethylenically unsaturated monomer having at least one fluoroalkyl group, a cross-linker, and, if needed, a polymerization initiator, dissolved in a nonpolar and or weakly polar solvent system. The membrane substrate saturated with the reactant system is exposed to a suitable energy source to effect polymerization and cross linking of the monomer.

Abstract: A process is provided for rapidly and non-destructively evaluating the particle retention characteristics of porous membranes using a novel liquid-porosimetric technique. A ratio of two membrane permeabilities is measured at preselected operating conditions using a pair of mutually immiscible fluids, one of which is employed as a membrane wetting agent and the other used as an intrusion fluid. The first operating condition, a particular transmembrane pressure, is chosen so as to selectively intrude those pores accessible to a given sized particle, such as a virus. The second operating condition, either a second preselected transmembrane pressure or a water permeability measurement, is chosen such that nearly all of the membrane pores are intruded. The ratio of the two permeabilities obtained with each set of operating conditions is thus the percentage of total flow through the membrane pores accessible to a given sized particle.

Abstract: A cassette for conducting gel electrophoresis separation of samples is provided comprising two spaced apart flat plates wherein at least one flat plate has well spacers secured thereto.A space between the plate is filled with an electrically conductive gel. The well spacers are electrically conductive.

Abstract: A sample preparation process and apparatus are provided for samples to be analyzed subsequently, such as by liquid chromatography. The sample is passed in contact with an ion exchange polymer which is characterized by being capable of facilitating removal of one or more undesired ions from the sample to be replaced with an ion transferred from the bound exchange site of the polymer and through the polymer. The polymer is prewashed with water to remove substantially all leachable species from the polymer. In one embodiment, the polymer is coated with a color indicator capable of changing color when the polymer is depleted of the ion to be transferred therefrom. The ion exchange capacity of the apparatus can be significantly expanded by using a counter ion donating solution capable of replacing the bound ions at the ion exchange sites as they become exchanged for the undesired ions from the sample.

Abstract: A spiral wound liquid separation device enclosed within a housing and a cover for the housing is provided with a seal which separates liquid feed to the device from liquid retentate produced by the device. The seal is of unitary construction with one end sealed to the outside surface of the spiral wound separation device and with a second end positioned between the housing and the cover under compression.

Abstract: A product having a porous polymeric structure is formed from a non-porous polymeric sheet by sequential contact of the non-porous sheet with a solvent for the sheet and then a non-solvent for the sheet. The porous product can be porous through all or a portion of its thickness.

Abstract: An apparatus and a system are provided for delivering a peritoneal dialysis solution to a patient. A connector containing a first set of conduit segments and a loader containing a second set of conduit segments are mated together such as with a mating set of tracks and slots so that the two sets of conduit segments form a plurality of conduits that are each sealed from the other conduits. The loader is provided with a device for mating the conduit segments together in sealed relationship such as an eccentrically mounted rotatable cylinder and a platen in contact with the cylinder. The apparatus permits delivery of the dialysis solution to the patient and removal of the solution subsequently from the patient.

Abstract: A solid component of a solid composition admixed with an aqueous medium is recovered by clarification and extraction in a common apparatus. An organic solvent for the solid component is admixed with the solid composition in the presence of the aqueous medium and the organic solvent is clarified in the apparatus by filtration with a filter which is not degraded by the organic solvent.