title: Isolation, characterization, and stability of discretely-sized nanolipoprotein particles assembled with apolipophorin-III.
abstract: BACKGROUND
  Nanolipoprotein particles (NLPs) are discoidal, nanometer-sized particles comprised of self-assembled phospholipid membranes and apolipoproteins. NLPs assembled with human apolipoproteins have been used for myriad biotechnology applications, including membrane protein solubilization, drug delivery, and diagnostic imaging. To expand the repertoire of lipoproteins for these applications, insect apolipophorin-III (apoLp-III) was evaluated for the ability to form discretely-sized, homogeneous, and stable NLPs.
  
  
  METHODS
  Four NLP populations distinct with regards to particle diameters (ranging in size from 10 nm to >25 nm) and lipid-to-apoLp-III ratios were readily isolated to high purity by size exclusion chromatography. Remodeling of the purified NLP species over time at 4 degrees C was monitored by native gel electrophoresis, size exclusion chromatography, and atomic force microscopy. Purified 20 nm NLPs displayed no remodeling and remained stable for over 1 year. Purified NLPs with 10 nm and 15 nm diameters ultimately remodeled into 20 nm NLPs over a period of months. Intra-particle chemical cross-linking of apoLp-III stabilized NLPs of all sizes.
  
  
  CONCLUSIONS
  ApoLp-III-based NLPs can be readily prepared, purified, characterized, and stabilized, suggesting their utility for biotechnological applications.
authors.affiliation: Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California, United States of America.
authors.forename: Nicholas O
authors.initials: NO
authors.lastname: Fischer
authors.forename: Craig D
authors.initials: CD
authors.lastname: Blanchette
authors.forename: Brent W
authors.initials: BW
authors.lastname: Segelke
authors.forename: Michele
authors.initials: M
authors.lastname: Corzett
authors.forename: Brett A
authors.initials: BA
authors.lastname: Chromy
authors.forename: Edward A
authors.initials: EA
authors.lastname: Kuhn
authors.forename: Graham
authors.initials: G
authors.lastname: Bench
authors.forename: Paul D
authors.initials: PD
authors.lastname: Hoeprich
mesh_terms: D000818:Animals; D001053:Apolipoproteins / Q000737:chemistry*; D012831:Bombyx / Q000737:chemistry; D006801:Humans; D019476:Insect Proteins / Q000737:chemistry*; D008074:Lipoproteins / Q000737:chemistry*; D018402:Manduca / Q000737:chemistry; D018625:Microscopy, Atomic Force; D053758:Nanoparticles / Q000737:chemistry*
chemical_list: D001053:Apolipoproteins; D019476:Insect Proteins; D008074:Lipoproteins; C042470:apolipophorin III