Abstract: Perfectly spherical, smooth and uniform microcapsules, which may contain living cells, are produced having a diameter less than 700 .mu.m by employing an electrostatic droplet generator. A droplet is suspended from a pointed source, such as a needle, and is charged with high static voltage. A collecting vessel or ring device is charged with opposing polarity and attracts the droplet. When a voltage potential threshold is passed, the droplet moves from the source to the collecting vessel. The voltage pulse height, pulse frequency and length, and extrusion rate of the droplets are adjustable so that predetermined sizes of droplets may be repeatedly generated and collected.

Abstract: A semi-automated procedure for the isolation of Islets from the pancreata of different species is described. Pancreatic tissue first is treated to free the Islets from other pancreatic tissue. Enzyme digestion generally is used at least partially to achieve this effect. After separation of the Islet suspension from pancreatic debris, the suspension is subjected to multiple filtration to separate the Islets, which then are recovered from the filter.

Abstract: Living tissue or cells, for example, islets of Langerhans, are microencapsulated for implantation in the body for long term treatment of diabetes or other disease requiring organ transplantation. The microcapsules take the form of a biocompatible semi-permeable hydrogel membrane based on polylysine which permits the passage of materials and oxygen to the cells and metabolic products from the cells while retaining the cells encapsulated. The biocompatible semi-permeable membrane has an outer negatively-charged surface, which, combined with a controlled thickness of polylysine of molecular weight from 10,000 to 30,000 daltons, imparts to the microcapsules the ability to maintain long term effectiveness.

Abstract: A new cell line which is morphologically very similar to the beta cell of the Islets of Langerhans is obtained by transformation of pancreatic bovine cells. The transformed cells contain the diploid number of chromosomes for the bovine species and produce insulin which may be extracted.

Abstract: The artificial endocrine pancreas device comprises a container in which are provided one, or more, hollow fibres; in the container and on the outside of the fibres are placed pancreatic islet cells; each fibre has a porosity allowing substances of molecular weight less than 100,000 Daltons to pass through so that blood passing in the hollow fibres can pass nutrients to the cells and pick up hormones, but no antigen or antibody with a molecular weight above 100,000 Daltons can pass through.