Abstract: The invention relates to compositions and methods for the safe delivery of a bioactive agent to an animal. Preferably, the bioactive agent is a vaccine, and more preferably, the bioactive agent is a virus.

Abstract: Tissue joining devices of one or more bending, interconnecting, or magnetically attractive components (1, 2) are provided. Methods for delivering bioactive agents (3) via these tissue joining devices (1, 2) are also provided.

Abstract: Multifunctional systems for delivery of bioactive compounds incorporated within or between polymeric fibers in a matrix are provided. Also provided are methods of delivering bioactive compounds via implementation, coating and/or wrapping of these systems and methods for modulating the rate of release of bioactive compounds from these delivery systems.

Abstract: Methods for producing polymer-based microcapsules and nanocapsules for use in diagnostic imaging and delivery of bioactive compounds as well as targeted imaging and delivery to selected tissues and cells are provided. Compositions containing these microcapsules and nanocapsules for use in diagnostic imaging and delivery of bioactive agents are also provided. Methods for enhancing delivery of nanocapsules via ultrasound are also provided.

Abstract: Methods for producing surfactant-stabilized and polymer-based microcapsules and nanocapsules for use in diagnostic imaging and delivery of bioactive compounds as well as targeted imaging and delivery to selected tissues and cells are provided. Compositions containing these microcapsules and nanocapsules for use in diagnostic imaging and delivery of bioactive agents are also provided.

Abstract: Methods for producing echogenic polymer microcapsules and nanocapsules for use in diagnostic imaging and delivery of bioactive compounds as well as targeted imaging and delivery to selected tissues and cells are provided. Compositions containing these echogenic polymer microcapsules and nanocapsules for use in diagnostic imaging and delivery of bioactive agents are also provided.

Abstract: Methods and apparatus for enhancing the capabilities of ultrasonic techniques through use of ultraharmonics are provided.

Abstract: Hollow polymer microcapsules are made by the method of dissolving a film-forming polymer in a volatile nonaqueous solvent; dispersing into the polymer solution finely divided particles of a volatilizable solid core material; inducing formation of a solid polymer coating on the particulate solid core material in the nonaqueous liquid mixture to produce polymer microcapsules having an encapsulated core of particulate core material; recovering the polymer microcapsules from the nonaqueous liquid mixture; and removing the encapsulated core material from the microcapsules to make hollow polymer microcapsules. Gas-filled polymer microcapsules that are made according to the method of this invention are useful in medical applications such as imaging contrast agents because they may be prepared to precisely controlled size specifications.

Abstract: Compositions, methods for preparing and methods of using contrast agent-filled polymeric microparticles for imaging are disclosed. In a preferred embodiment, air-encapsulating microparticles are formed by ionotropically gelling synthetic polyelectrolytes such as poly(carboxylatophenoxy)phosphazene, poly(acrylic acid), poly(methacrylic acid) and methacrylic acid copolymers (Eudragit's) by contact with multivalent ions such as calcium ions. In the preferred embodiment, the average size of the microparticles is less than seven .mu.m so that they are suitable for injection intravenously. The polymeric microparticles are stable to imaging and display high echogenicity, both in vitro and in vivo. Due to their in vivo stability their potential application is extended beyond vascular imaging to liver and renal diseases, fallopian tube diseases, detecting and characterizing tumor masses and tissues, and measuring peripheral blood velocity.

Abstract: Compositions, methods for preparing and methods of using air-filled polymeric microcapsules for ultrasound imaging are disclosed. Air-encapsulating microcapsules are formed by ionotropically gelling synthetic polyelectrolytes such as poly(carboxylatophenoxy)phosphazene, poly(acrylic acid), poly(methacrylic acid) and methacrylic acid copolymers (Eudragit's) by contact with multivalent ions such as calcium ions. In the preferred embodiment, the average size of the microcapsules is less than seven .mu.m so that they are suitable for injection intravenously. The polymeric microcapsules are stable to imaging and display high echogenicity, both in vitro and in vivo. Due to their in vivo stability their potential application is extended beyond vascular imaging to liver and renal diseases, fallopian tube diseases, detecting and characterizing tumor masses and tissues, and measuring peripheral blood velocity.

Abstract: The present invention is a mixture including a solvent, a first surfactant and a second, dispersible surfactant different from the first surfactant, the mixture having stabilized gas microbubbles formed therein by sonication. The gas microbubbles are useful in ultrasonic diagnostics. Preferably the first surfactant is substantially soluble in the solvent and the second surfactant is substantially insoluble in the solvent. The present invention also includes a process for preparing the stabilized gas microbubbles and a method for altering the contrast of an ultrasonic image using the microbubbles as a contrast agent.

Abstract: A controlled release system for delivery of a biologically-active substance. In one embodiment, there is a delayed release of a biologically-active substance. In a second embodiment, the delayed release is preceded by an initial release of biologically active substance. In other variations of the system, there are mulitple discrete releases over time or a continuous slow release combined with discrete releases. The delayed exposure is achieved through the design and construction of the system, specifically, formation of ionically-coated microcapsules around the biologically-active substance in conjunction with a microcapsule core-degrading enzyme. Release of active substance takes place in a burst at such a time as the core degrading enzyme has reduced the core to a molecular weight too low to support enough interaction with the cationic skin to maintain its integrity as a skin.

Abstract: A system for controlled release both in vivo and in vitro of entrapped substances, either at a constant rate over a period of time or in discrete pulses, is disclosed. Biologically active substances, such as drugs, hormones, enzymes, genetic material, antigens including viruses, vaccines, or inorganic material such as dyes and nutrients, are entrapped in liposomes which are protected from the biological environment by encapsulation within semi-permeable microcapsules or a permeable polymeric matrix. Release of the entrapped substance into the surrounding environment is governed by the permeability of both the liposome and surrounding matrix to the substance.

Abstract: A system for controlled release both in vivo and in vitro of entrapped substances, either at a constant rate over a period of time or in discrete pulses, is disclosed. Biologically active substances, such as drugs, hormones, enzymes, genetic material, antigens including viruses, vaccines, or inorganic material, such as dyes and nutrients, are entrapped in liposomes which are protected from the biological environment by encapsulation within semi-permeable microcapsules. Release of the entrapped substance into the surrounding environment is governed by the permeability of both the liposome and microcapsule walls to the substance.

Abstract: An apparatus for removing material from a biological solution consisting of a reactor chamber having an inlet and an outlet, a bioactive compound immobilized on particular supports within the reactor, means for retaining the particular supports within the reactor, means for recirculating the solution and the supports at a high flow rate within the reactor, and means for agitating or dispersing the recirculating solution-support mixture throughout the reactor chamber so as to prevent packing of the supports while not subjecting the solution to excessive or damaging forces.In the given example, an apparatus for the extracorporeal removal of heparin from blood is provided. Heparinase is immobilized on cross-linked agarose beads recirculated at a high flow rate through the reactor. Agitation of the blood-bead mixture sufficient to prevent packing of the beads within the reactor chamber is provided by means of a series of openings in the recirculation tube dispersing the mixture throughout the chamber.