Preparation and purification of synthetic protein nanoparticulates.

The protein nanostructure used in this study (bovine serum albumin; BSA nanoparticles) were fabricated with an average nanoparticle diameter 150 nm based on the principle of coacervation. Practical recovery of nanoparticulate mimics, of products such as plasmid DNA and viruses as putative gene therapy vectors from model systems, has been studied. The adsorbents employed in this study for the recovery of nanoparticles had one of four discrete designs i.e. microporous (pore size <0.2 microm), macroporous (pore size >0.8 microm), solid phase (nonporous) and pellicular (pore size <0.5 microm). Soluble protein was included in the study to represent cellular components of complex feedstocks and the separation of assemblies from components, while particulate protein served as surrogate size and charge mimics of less easily sourced viral and plasmid gene therapy vectors. Candidate adsorbents were physically characterised to assess their suitability for fluidised-bed operation, biochemically characterised exploiting batch-binding experimentation and laser scanning confocal microscopy. The adsorptive capacity of nanoparticulate products was strongly influenced by the physical design of the adsorbents, and microporous adsorbents appeared to be less suited for the recovery of nanoparticulate products. The generic application of such adsorbents for the recovery of nanoparticulate bioproducts is discussed.