Abstract: A diffusion cell to facilitate the automatic or manual removal of test aliquots of liquid from a receptor chamber of the diffusion cell so as to determine percantaneous absorption through a membrane of a substance from a donor chamber into a receptor chamber of the diffusion cell. There is utilized a capillary port through which the test aliquot is to be removed. A refilling tube connects also with the receptor chamber to add receptor liquid into the receptor chamber as the test aliquot is being removed. A quick release clamping apparatus secures the donor housing which contains the donor chamber tightly to the main housing of the diffusion cell.

Abstract: A liquid sample collector and liquid return apparatus which takes the form of a first tube which has an open lower end which is to be submerged within a liquid source. This first tube is connected to a vacuum source located exteriorly of the liquid source which is to cause removal of aliquots (or samples). Mounted about a portion of the first tube is a second tube which has an open outer end which is spaced from the surface of the liquid source. This open outer end forms an annulus about the first tube. A valving arrangement is provided so that any liquid that is returned to the liquid source is returned only through the second tube.

Abstract: A mobile media dispensing apparatus in the form of a portable cart which has a plurality of vessels. The apparatus of this invention is to simultaneously deliver to testing vessels of a separate dissolution test apparatus an identical volume of a preheated, filtered, deaerated media within three minutes of time. The media of each vessel is to be used by depositing a pill therein with the dissolution rate to be determined of the pill within the media of each vessel.

Abstract: An alignment verification device for a rotating shaft that utilizes a calibration adapter assembly that has a longitudinal center axis. Mounted on the calibration adapter assembly in a concentric manner is a dial indicator. The stem of the dial indicator is to be placed against a precisely manufactured alignment shaft which has been temporarily substituted for a rotating shaft whose axis of rotation is to coincide with the longitudinal center axis of the calibration adapter assembly. Rotational relative movement between the stem and the shaft will produce readings on the dial indicator with any deviations of the axis of rotation from the longitudinal center axis being discovered by the dial indicator. A zeroing mechanism is to be utilized in conjunction with the calibration adapter assembly prior to connection with the rotating shaft. The zeroing mechanism takes the form of a gauge plug which is to be mounted in a close tolerance manner within a through hole formed within the calibration adapter assembly.

Abstract: An automated sample changing chemical analysis system for sequentially analyzing a series of samples such as pharmaceutical chemical samples, the system being particularly useful for dissolution rate testing. A pressure/vacuum source provides motivation for withdrawing each sample from its respective source in sequence through a sample selector valve and transporting the sample to the flow cell of a chemical analyzer such as an U.V. Spectrophotometer, and then returning all or part of the sample to its source through the same selector valve and purging the flow cell and conduits back to the sample source. In one form each sample is simply drawn by vacuum from its source through the selector valve into the flow cell and then the entire sample is returned after analysis, by air pressure, back through the selector valve to the source, while in another form a diluent or reagent is mixed with the sample in an intermediate step to bring the sample within the testing range of the analyzer.