title: Formation of spherical protein nanoparticles without impacting protein integrity.
abstract: Protein formulation at the nanoscale is challenging because of protein susceptibility to chemical and physical degradation during processing. Herein, we present a straightforward method to prepare spherical protein nanoparticles by co-lyophilizing five structurally different enzymes (horseradish peroxidase, carbonic anhydrase, lysozyme, subtilisin Carlsberg and α-chymotrypsin) with methyl-β-cyclodextrin followed by suspension of the powders in ethyl acetate. The size distribution was narrow and varied from 88 ± 14 to 148 ± 16 nm as determined by dynamic light scattering. Scanning and transmission electron micrographs confirmed the size and spherical morphology of the protein nanoparticles. Residual activities for all enzymes tested were 100% upon dissolving the nanoparticles in buffer and no insoluble aggregates were formed.
authors.affiliation: Department of Chemistry, University of Puerto Rico, Río Piedras Campus, PO Box 23346, San Juan, PR 00931-3346, USA.
authors.forename: Brenda L
authors.initials: BL
authors.lastname: Montalvo
authors.forename: Yamaris
authors.initials: Y
authors.lastname: Pacheco
authors.forename: Brian A
authors.initials: BA
authors.lastname: Sosa
authors.forename: Denisse
authors.initials: D
authors.lastname: Vélez
authors.forename: Giselle
authors.initials: G
authors.lastname: Sánchez
authors.forename: Kai
authors.initials: K
authors.lastname: Griebenow