This invention relates to methods for the stabilization, storage and delivery of biologically active macromolecules, such as proteins, peptides and nucleic acids. In particular, this invention relates to protein or nucleic acid crystals, formulations and compositions comprising them. Methods are provided for the crystallization of proteins and nucleic acids and for the preparation of stabilized protein or nucleic acid crystals for use in dry or slurry formulations. The present invention is further directed to encapsulating proteins, glycoproteins, enzymes, antibodies, hormones and peptide crystals or crystal formulations into compositions for biological delivery to humans and animals. According to this invention, protein crystals or crystal formulations are encapsulated within a matrix comprising a polymeric carrier to form a composition. The formulations and compositions enhance preservation of the native biologically active tertiary structure of the proteins and create a reservoir which can slowly release active protein where and when it is needed. Methods are provided preparing stabilized formulations using pharmaceutical ingredients or excipients and optionally encapsulating them in a polymeric carrier to produce compositions and using such protein crystal formulations and compositions for biomedical applications, including delivery of therapeutic proteins and vaccines. Additional uses for the protein crystal formulations and compositions of this invention involve protein delivery in human food, agricultural feeds, veterinary compositions, diagnostics, cosmetics and personal care compositions.