The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 31, 1995
Filed:
Sep. 23, 1993
Taylor G Wang, Nashville, TN (US);
Vanderbilt University, Nashville, TN (US);
Abstract
Microspheres of a substantially uniform diameter are produced having a central portion composed of a solution of a polyanion containing a biological material, and an outer permeable membrane enclosing the central portion which is a complex of the polyanion and a polycation. The biological material has a molecular size greater than 150,000 Daltons, and the membrane has a porosity such that the biological material does not permeate the membrane. The biological material may comprise living cells or living tissue. The microspheres are formed by individually enveloping falling droplets of a polyanion solution with a collapsing annular sheet of a polycation solution while the sheet is traveling downwardly at the same velocity as the droplets.