Processing of nanoparticulate bioproducts: application and optimisation of aqueous two-phase systems

✍ Scribed by Simon G Walker; Andrew Lyddiatt

• Publisher: Wiley (John Wiley & Sons)
• Year: 1999
• Tongue: English
• Weight: 243 KB
• Volume: 74
• Category: Article
• ISSN: 0268-2575
• DOI: 10.1002/(sici)1097-4660(199903)74:3<250::aid-jctb25>3.0.co;2-w

✦ Synopsis

A simple aqueous two-phase system (ATPS) has been identiüed and implemented for the fractionation of small inclusion bodies (IBs) from debris in microbial cell homogenates. Many problems imposed by processing üne particulates are circumvented. At pH 9.4, the greatest IB recoveries were obtained with PEG 8000/phosphate systems (10/10% w/w) where IBs accumulated as a discrete sediment within the salt-rich lower phase. The majority of micronised debris partitioned as a discrete interphase. Manipulation of the system pH recommended operation above the isoelectric point of the target product to avoid debris ýocculation which undermined partition selectivity. System optimisation was achieved by the addition of 0.4 mol dm-3 NaCl (at pH 9.4) where IB recovery increased to 87% of the load concomitant with preferential fractionation of debris to the interphase. The generic application of ATPS to the bioprocessing of nanoparticles is discussed.