Abstract: A method for encapsulating a biomacromolecule in a pore-containing polymer comprising the steps of providing an encapsulating solution containing the biomacromolecule and the pore-containing polymer; contacting the biomacromolecule with the pore-containing polymer for a time sufficient for the biomacromolecule to enter the pores of the pore-containing polymer; and rearranging the polymer such that the surface pores of the polymer are closed thus encapsulating the biomacromolecule in the pore-containing polymer.

Abstract: Methods for enhancing immunogenic response to an antigen, particularly a peptide antigen in a mammalian subject. The method comprises administering a biodegradable polymeric delivery system which comprises one or more antigens of interest and a biologically effective amount of one or more basic additives to the mammalian subject. In a highly preferred embodiment, the basic additive in MgCO3, and the biodegradable polymeric delivery system is a PLGA microparticle. The present invention also relates to the immunogenic compositions used in the present method.

Abstract: Methods for reducing or inhibiting the irreversible inactivation of water-soluble biologically active agents in biodegradable polymeric delivery systems which are designed to release such agents over a prolonged period of time, such as PLGA delivery systems are provided. The method comprises preparing a PLGA delivery systems whose microclimate, i.e. the pores where the active agent resides, uniformly or homogenously maintain a pH of between 3 and 9, preferably between 4 and 8, more preferably between 5 and 7.5 during biodegradation.

Abstract: Methods for reducing or inhibiting the irreversible inactivation of water-soluble biologically active agents in biodegradable polymeric delivery systems which are designed to release such agents over a prolonged period of time, such as PLGA delivery systems are provided. The method comprises preparing a PLGA delivery systems whose microclimate, i.e. the pores where the active agent resides, uniformly or homogenously maintain a pH of between 3 and 9, preferably between 4 and 8, more preferably between 5 and 7.5 during biodegradation.

Abstract: A delivery system and a method for sustained release of formaldehyde-treated vaccine antigens wherein the antigens are stabilized by stabilizing agents mixed with the formaldehyde-treated antigens and then dispersed within a biocompatible polymer matrix. The stabilizing agents inhibit formaldehyde mediated aggregation of formaldehyde-treated vaccine antigens by greater than 60% compared to antigens incubated without stabilizing agents. Stabilizing agents may be selected from formaldehyde-interacting amino acids, basic additives, and mono, di-, or polysaccharides. The delivery system may be biodegradable. The formaldehyde-treated vaccine antigens my be tetanus toxoid, diphtheria toxoid, or both tetanus toxoid and diphtheria toxoid.

Abstract: Methods for reducing or inhibiting the irreversible inactivation of water-soluble biologically active agents in biodegradable polymeric delivery systems which are designed to release such agents over a prolonged period of time, such as PLGA delivery systems are provided. The method comprises preparing a PLGA delivery systems whose microclimate, i.e. the pores where the active agent resides, uniformly or homogenously maintain a pH of between 3 and 9, preferably between 4 and 8, more preferably between 5 and 7.5 during biodegradation.