Vortex fluidic entrapment of functional microalgal cells in a magnetic polymer matrix

Abstract

Composite materials based on superparamagnetic magnetite nanoparticles embedded in polyvinylpyrrolidone (PVP) are generated in a continuous flow vortex fluidic device (VFD). The same device is effective in entrapping microalgal cells within this material, such that the functional cells can be retrieved from aqueous dispersions using an external magnet.

Harvesting of freshwater and marine microalgae by common flocculants and magnetic microparticles

“…Over the past years, several magnetic particles have been employed for the separation or entrapment of microalgae. These materials include uncoated iron oxides (Bitton et al 1975;Xu et al 2011;Prochazkova et al 2013), surface functionalized iron oxide nanoparticles with cationic polyacrylamides (Wang et al 2014), chitosan (Eroglu et al 2012;Lim et al 2012), polyvinylpyrrolidone (Eroglu et al 2013), and cationic polyelectrolytes (Toh et al 2014a). Among various separation methods for microalgal harvesting, magnetic separation exhibits high recovery efficiency at short operation time, and no residual magnetic nanoparticles remain in the liquid after separation (Xu et al 2011).…”

Microencapsulation of bacterial strains in graphene oxide nano-sheets using vortex fluidics

“…10,16 In the VFD, a rapidly rotating tube generates a thin microuidic lm with rapid micro-mixing of reagents therein, and the mechanoenergy in the lm is effective in increasing reaction rates, and therefore reducing the processing times. 33 Importantly, the VFD can be operated in the conned mode and also continuous ow mode, and it has a diversity of processing capabilities, including in organic synthesis, [33][34][35][36][37] controlled growth of the polymorphs of calcium carbonate, 38 formation of mesoporous silica at room temperature with control over the pore size, 39 compacting single walled carbon nanotube into toroidal structures, 40 exfoliation of graphene and boron nitride, 41 controlled decoration of nanoparticles on 2D nanomaterials, [42][43][44] preparation of functional hybrid bio-nanomaterials, 10,16,45 and the refolding of proteins.…”

Magnetically modified microalgae and their applications

“…The basic procedures used for the magnetic modification of algal cells involve non-specific attachment of magnetic nanoparticles (MNPs) (e.g. by magnetic fluid treatment) (Safarikova et al, 2008) or magnetic microparticles (Prochazkova et al, 2013b) onto the cell surface, polymer-modified iron oxides particles binding (Fakhrullin et al, 2010;Toh et al, 2014c), covalent immobilization of magnetic particles on algae cell surface or vice versa (Venu et al, 2013), specific interactions with immunomagnetic nano-and microparticles (Aguilera et al, 1996;Aguilera et al, 2002;Safarik & Safarikova, 1999) or entrapment (together with magnetic particles) into biocompatible polymers (Eroglu et al, 2013). Magnetic properties of the modifiers are mainly due to the presence of nano-or microparticles of magnetite (Fe 3 O 4 ) or maghemite (g-Fe 2 O 3 ) or their mixtures.…”

“…High entrapment efficiency (up to 95%) was obtained. Entrapped cells can be separated from the PVP matrix using mild-sonication (Eroglu et al, 2013).…”