Effect of salinity and nanoparticle polydispersity on UF membrane retention fouling

Abstract

In this study, the retention potential and the fouling of ultrafiltration (UF) multichannel hollow fiber membrane regarding nanoparticles (NPs) have been assessed. Filtration experiments of fluorescent 10 nm and 1.5 nm NPs (respectively NP-10 and NP-1.5) suspensions filtered individually were carried out under different transmembrane pressures. A complexification of the feed suspension through the mix of NPs sizes and/or the salinity adding have been investigated. The retention rate (RR), the fouling location and the membrane productivity have been analyzed and compared in each case to determine the influence of salinity and polydispersity of the feed suspensions on NP retention. Results show that RR of NP-10 stays constant when NPs are filtered in ideal suspension (NP-10 / ultrapure water), or when they are filtered with NP-1.5 and/or with 50 mmol L −1 of NaCl and reaches at least 99%. However, RR of NP-1.5 is modified by the presence of NP-10 and/or 50 mmol L −1 of NaCl. This retention rate is considerably decreased by the complexification of suspensions tested. Estimation of NPs quantity blocked at the membrane at the end of the filtration by mass balance showed no significative variation for NP-1.5 (relative to the RR obtained) while a larger quantity of NP-10 remained blocked at the membrane with the adding of NP-1.5 and/or salts in feed suspension. Location of NPs by Confocal Laser Scanning Microscopy (CLSM) at the end of the filtration showed that filtered individually, NP-10 are blocked in membrane skin and on membrane surface while NP-1.5 are blocked in the entire membrane material. Filtered simultaneously, the location of these two sizes of NPs is not modified but NP-1.5 seems to form clusters in the membrane material and the participation of NP-10 and NP-1.5 to the deposit formed on the membrane surface is increased. The adding of salinity leads to the same observations than the filtration of both sizes mixed.

Retention and Fouling during Nanoparticle Filtration: Implications for Membrane Purification of Biotherapeutics

“…In addition to these studies of viral vector purification, a number of investigators have looked at the ultrafiltration of model nanoparticles that may be significant environmental toxins. For example, Le Hir et al [ 16 ] evaluated the effects of salinity and polydispersity on the ultrafiltration of small (1.5 and 10 nm) nanoparticles and noted significant effects of intermolecular interactions between the nanoparticles and with the membrane. Jassby et al [ 17 ] examined the filtration of C60 fullerenes in the presence of different salts, showing that the addition of divalent cations led to the formation of large aggregates that were more highly retained by a ceramic membrane.…”

A review of in situ real-time monitoring techniques for membrane fouling in the biotechnology, biorefinery and food sectors

“…Off-line CLSM membrane characterization has also been used by Gao et al [45] in an attempt to understand the mechanisms governing the adsorption of organic matter on aged polyvinylidene fluoride (PVDF) membranes. In a more recent study, CLSM has has been used to characterize the retention of nanoparticles (1.5 and 10 nm) by UF PES hollow-fiber membranes [46].…”

Role of Microfiltration Membrane Morphology on Nanoparticle Purification to Enhance Downstream Purification of Viral Vectors

“…Synthetic nanoparticles have been increasingly utilized as model particles in process optimization studies. − This approach enables researchers to investigate and optimize various parameters, such as buffer and surfactant concentrations, for enhanced viral vector-like nanoparticle throughput . Several investigators have considered the use of model particles as contaminants in water treatment applications. , In earlier work, done by Chu et al, the retention of 30 nm polystyrene nanoparticle suspensions was investigated as a model for AAV3 . Moreover, a recent study investigating single pass tangential flow filtration of 100 nm nanoparticles indicated they are a good model for lentivirus .…”

“…28 Several investigators have considered the use of model particles as contaminants in water treatment applications. 29,30 In earlier work, done by Chu et al, the retention of 30 nm polystyrene nanoparticle suspensions was investigated as a model for AAV3. 28 Moreover, a recent study investigating single pass tangential flow filtration of 100 nm nanoparticles indicated they are a good model for lentivirus.…”