Abstract: A process for preparing nanoparticles and microparticles is provided. The process involves forming a mixture of a polymer and a solvent, wherein the solvent is present in a continuous phase and introducing the mixture into an effective amount of a nonsolvent to cause the spontaneous formation of microparticles.

Abstract: A process is provided for making dry, micronized particles of an agent, such as a drug. The method includes (a) dissolving a macromolecular material, preferably a polymer, in an effective amount of a solvent, to form a solution; (b) dissolving or dispersing the agent in the solution to form a mixture; (c) freezing the mixture; and (d) drying by vacuum the mixture to form solid particles of the agent dispersed in solid macromolecular material. The micronization in this process occurs directly in a macromolecular matrix and hardening of the particles of agent by solvent removal takes place by lyophilization of the bulk matrix, which stabilizes the drug particles during hardening and prevents coalesence, thereby resulting in smaller final drug particles. The method is particularly preferred for protein agents. The process can be used in conjunction with a standard microencapsulation technique, typically following separation of the agent from the macromolecular matrix.

Abstract: Bioactive agents may be reproducibly converted into particles having diameters in the range of about 5 to about 2000 nanometers (nm). Conversion is accomplished by dissolving the bioactive agent in a solvent for the bioactive agent, and rapidly altering the polarity of the solution to make it a non-solvent for the bioactive agent, for example by diluting the bioactive agent solution with an excess of a liquid that is a non-solvent for the bioactive agent but is miscible with the solvent. Precipitated bioactive agent nanoparticles are collected by centrifugation, filtration or lyophilization. The nanoparticles have a relatively narrow size distribution, and the average diameter can be controlled by choice of solvent and non-solvent. The nanoparticles are typically amorphous. A surfactant may be added to ensure dispersion of the particles when administered. In the preferred embodiment, the bioactive agent is a drug with low aqueous solubility.

Abstract: A process for preparing nanoparticles and microparticles is provided. The process involves forming a mixture of a polymer and a solvent, wherein the solvent is present in a continuous phase and introducing the mixture into an effective amount of a nonsolvent to cause the spontaneous formation of microparticles.

Abstract: Methods for inducing a thermoplastic polymer, which can be non-mesogenic, to exhibit liquid crystalline properties have been developed. The method includes the steps of (a) heating the polymer from an initial temperature below its glass transition temperature (Tg) to a temperature greater than its Tg and below its melting temperature (Tm); (b) exposing the polymer to a pressure greater than about 2 metric tons/in2, preferably between about 2 and 10 metric tons/in2, preferably for at least about one minute, while maintaining the temperature greater than its Tg; and (c) cooling the polymer below the Tg while maintaining the elevated pressure. Unlike many prior art transition processes which are reversible, this process provides a liquid crystal state that can be maintained for years at ambient conditions. In a preferred embodiment, the plastics are bioerodible thermoplastic polymers, such as polyanhydrides, some polyesters, polyamides, and polyaromatics.

Abstract: The invention involves methods and products for oral gene therapy. Genes under the control of promoters are protectively contained in microparticles and delivered to cells in operative form, thereby obtaining noninvasive gene delivery for gene therapy.

Abstract: Methods for inducing a thermoplastic polymer, which can be non-mesogenic, to exhibit liquid crystalline properties have been developed. The method includes the steps of (a) heating the polymer from an initial temperature below its glass transition temperature (Tg) to a temperature greater than its Tg and below its melting temperature (Tm); (b) exposing the polymer to a pressure greater than about 2 metric tons/in2, preferably between about 2 and 10 metric tons/in2, preferably for at least about one minute, while maintaining the temperature greater than its Tg; and (c) cooling the polymer below the Tg while maintaining the elevated pressure. Unlike many prior art transition processes which are reversible, this process provides a liquid crystal state that can be maintained for years at ambient conditions. In a preferred embodiment, the plastics are bioerodible thermoplastic polymers, such as polyanhydrides, some polyesters, polyamides, and polyaromatics.

Abstract: A process for preparing nanoparticles and microparticles is provided. The process involves forming a mixture of a polymer and a solvent, wherein the solvent is present in a continuous phase and introducing the mixture into an effective amount of a nonsolvent to cause the spontaneous formation of microparticles.

Abstract: A process is provided for making dry, micronized particles of an agent, such as a drug. The method includes (a) dissolving a macromolecular material, preferably a polymer, in an effective amount of a solvent, to form a solution; (b) dissolving or dispersing the agent in the solution to form a mixture; (c) freezing the mixture; and (d) drying by vacuum the mixture to form solid particles of the agent dispersed in solid macromolecular material. The micronization in this process occurs directly in a macromolecular matrix and hardening of the particles of agent by solvent removal takes place by lyophilization of the bulk matrix, which stabilizes the drug particles during hardening and prevents coalesence, thereby resulting in smaller final drug particles. The method is particularly preferred for protein agents. The process can be used in conjunction with a standard microencapsulation technique, typically following separation of the agent from the macromolecular matrix.

Abstract: A process is provided for making dry, micronized particles of an agent, such as a drug. The method includes (a) dissolving a macromolecular material, preferably a polymer, in an effective amount of a solvent, to form a solution; (b) dissolving or dispersing the agent in the solution to form a mixture; (c) freezing the mixture; and (d) drying by vacuum the mixture to form solid particles of the agent dispersed in solid macromolecular material. The micronization in this process occurs directly in a macromolecular matrix and hardening of the particles of agent by solvent removal takes place by lyophilization of the bulk matrix, which stabilizes the drug particles during hardening and prevents coalesence, thereby resulting in smaller final drug particles. The method is particularly preferred for protein agents. The process can be used in conjunction with a standard microencapsulation technique, typically following separation of the agent from the macromolecular matrix.

Abstract: Methods for inducing a thermoplastic polymer, which can be non-mesogenic, to exhibit liquid crystalline properties have been developed. The method includes the steps of (a) heating the polymer from an initial temperature below its glass transition temperature (Tg) to a temperature greater than its Tg and below its melting temperature (Tm); (b) exposing the polymer to a pressure greater than about 2 metric tons/in2, preferably between about 2 and 10 metric tons/in2, preferably for at least about one minute, while maintaining the temperature greater than its Tg; and (c) cooling the polymer below the Tg while maintaining the elevated pressure. Unlike many prior art transition processes which are reversible, this process provides a liquid crystal state that can be maintained for years at ambient conditions. In a preferred embodiment, the plastics are bioerodible thermoplastic polymers, such as polyanhydrides, some polyesters, polyamides, and polyaromatics.

Abstract: Methods for inducing a thermoplastic polymer, which can be non-mesogenic, to exhibit liquid crystalline properties have been developed. The method includes the steps of (a) heating the polymer from an initial temperature below its glass transition temperature (Tg) to a temperature greater than its Tg and below its melting temperature (Tm); (b) exposing the polymer to a pressure greater than about 2 metric tons/in2, preferably between about 2 and 10 metric tons/in2, preferably for at least about one minute, while maintaining the temperature greater than its Tg; and (c) cooling the polymer below the Tg while maintaining the elevated pressure. Unlike many prior art transition processes which are reversible, this process provides a liquid crystal state that can be maintained for years at ambient conditions. In a preferred embodiment, the plastics are bioerodible thermoplastic polymers, such as polyanhydrides, some polyesters, polyamides, and polyaromatics.

Abstract: The invention relates to methods and products for preventing and treating tumors. In particular the invention relates to the use of slow release microparticles containing cytokines, which are directly injected into a tumor, in order to treat the tumor, e.g., cause tumor regression or to prevent tumor growth or metastasis.

Abstract: The invention relates to methods and products for preventing and treating tumors. In particular the invention relates to the use of slow release microparticles containing IL-12, which are directly injected into a tumor, in order to treat the tumor or to prevent tumor growth or metastasis.

Abstract: The invention involves methods and products for oral gene therapy. Genes under the control of promoters are protectively contained in microparticles and delivered to cells in operative form, thereby obtaining noninvasive gene delivery for gene therapy.

Abstract: A process for preparing nanoparticles and microparticles is provided. The process involves forming a mixture of a polymer and a solvent, wherein the solvent is present in a continuous phase and introducing the mixture into an effective amount of a nonsolvent to cause the spontaneous formation of microparticles.

Abstract: A process for preparing nanoparticles and microparticles is provided. The process involves forming a mixture of a polymer and a solvent, wherein the solvent is present in a continuous phase and introducing the mixture into an effective amount of a nonsolvent to cause the spontaneous formation of microparticles.