Encapsulation of microparticles in teardrop shaped polymer capsules of cellular size
US6248321A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 14, 1999 |
| Grant date | Jun 19, 2001 |
| Priority date | — |
| Expiry date | Jan 14, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2984
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Microparticles such as propagules of eukaryotic biocontrol agents are encapsulated in cellular-scale polymer capsules that have a diameter similar to normal eukaryotic cells in a range of about 10 .mu.m to about 400 .mu.m. The microparticles are encapsulated by adding a hydrophobic dispersion medium such as a mixture of chloroform and hexane or a mixture of corn oil and n-hexadecane having a specific gravity of about 1 and containing an emulsifier such as lecithin to an aqueous suspension of the microparticles and a polymer matrix precursor such as alginate, agitating vigorously to form a stable emulsion of microscopic globules containing a microparticle, and adding the emulsion to an aqueous solution containing a polymerizing agent such as calcium chloride to polymerize and precipitate the globules to form microparticles encapsulated in polymer matrix capsules that may be of a teardrop shape having a length of 40-200% longer than the diameter. Precipitation of the globules is regulated by substantially matching the Specific Gravity of the hydrophobic dispersion medium and the aqueous suspension. The microparticle may be a viable propagule of a weed pathogenic fungus to provide a h…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.