Microencapsulation and electrostatic processing device

US6214300A · kind A · utility

Assignee

• The United States of America as represented by the Administrator of the National Aeronautics and Space Administration · US

Inventors

• Dennis R. Morrison · Kemah, US
• Benjamin Mosier · Houston, US
• John M. Cassanto · Downingtown, US

Key dates

• Filing date: May 15, 1998
• Grant date: Apr 10, 2001
• Expiry date: May 15, 2018

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01F33/30
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

A microencapsulation and electrostatic processing (MEP) device is provided for forming microcapsules. In one embodiment, the device comprises a chamber having a filter which separates a first region in the chamber from a second region in the chamber. An aqueous solution is introduced into the first region through an inlet port, and a hydrocarbon/polymer solution is introduced into the second region through another inlet port. The filter acts to stabilize the interface and suppress mixing between the two immiscible solutions as they are being introduced into their respective regions. After the solutions have been introduced and have become quiescent, the interface is gently separated from the filter. At this point, spontaneous formation of microcapsules at the interface may begin to occur, or some fluid motion may be provided to induce microcapsule formation. In any case, the fluid shear force at the interface is limited to less than 100 dynes/cm.sup.2. This low-shear approach to microcapsule formation yields microcapsules with good sphericity and desirable size distribution. The MEP device is also capable of downstream processing of microcapsules, including rinsing, re-suspension i…