Abstract: Improved immunogenic compositions and methods for producing antibodies to low molecular weight analytes are presented. In one series of embodiments particularly useful for production of antibodies having specificity for metal ions, nonimmunogenic polymers having natural metal ion-binding activity, typically alginates, are used, after contact with metal ions, as an immunogenic composition. In another series of embodiments, immunogens are enmeshed in a crosslinked protein network to create a potent immunogenic composition. In the latter embodiments, gelatins of cold-water fish prove surprisingly efficacious.

Abstract: A device for detecting the isoelectric end point in an isoelectric focusing system by electronically integrating, over successive time intervals, a characteristic of the electrical input to said zone as it varies with the increasing resistance of the zone. Most conveniently, the measured characteristic is the current through the zone which, under constant impressed voltage or power, asymptotically approaches a minimum value as the end point is reached.The measured characteristic is continually converted to a sequence of pulses indicative of the value of the characteristic. The end point is indicated when the difference between counts of these pulses over successive time intervals reaches a preselected value. At the end point, provision is made for replacement of the focusing voltage with a lower voltage to keep the ampholytes focused. A signal can be activated at the end point.

Abstract: A handling device for enabling a technician to dialyze a solution without direct contact with the solution to be dialyzed. The device comprises a polycarbonate rod having an internal bore and a test tube gripping element at one end. At the other end is clamped a section of dialysis tubing, there being a passageway from the test tube-gripping end through the internal bore and into the dialysis tubing. The dialysis tubing is knotted to form a dialysis bag. The rod is manipulated to grippingly engage over a test tube containing the solution to be dialyzed and the test tube is inverted to transfer its contents to the dialysis bag, after which the device is supported in inverted position with the bag in a dialysis bath. After dialysis, the device is removed and reversed, returning the dialyzed solution to the test tube.

Abstract: A hydratable or hydrated gel medium for use in bioassay of a test substance contains fixed in a localized zone a reagent for the test substance. Assays are conducted rapidly by diffusing the test substance followed by an indicator substance also reactive with the reagent into the zone and measuring a change in characteristics within the zone caused by the reaction of the indicator substance.