Preparation of elongated seamless capsules containing a coaxial rod and biological material
US5643773A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 1995 |
| Grant date | Jul 1, 1997 |
| Priority date | — |
| Expiry date | Apr 27, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S530/817
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Elongated seamless capsules containing biological material are prepared by a method in which a coagulant, which includes a cell suspension or other biological material, and a polymeric casting solution are extruded through a common extrusion port having at least two concentric bores, such that the coagulant is extruded through an inner bore and the polymeric casting solution is extruded through an outer bore. Extrusion of the coagulant is initiated subsequent to initiating delivery of the casting solution to form a capsule having a curved and smooth leading edge shape. Delivery of the coagulant is then shut off, and extrusion of the casting solution is terminated either immediately or after some predetermined time. This procedure can be modified to form in the capsule a coaxial rod that is connected to one end but not the other end of the capsule. This is accomplished by drawing casting solution into the inner bore after initiating extrusion of the casting solution through the outer bore, and then initiating delivery of the coagulant through the inner bore so as to coagulate the casting solution therein and form a rod, and ejecting the rod from the inner bore by pressure of the coa…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.