Magnetic separation of algae genetically modified for increased intracellular iron uptake

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:380

Article; Proceedings Paper

Buck, Amy^1,2  Moore, Lee R.²  Lane, Christopher D.³  Kumar, Anil³  Stroff, Clayton³  White, Nicolas³  Xue, Wei⁴  Chalmers, Jeffrey J.⁴  Zborowski, Maciej² 

[1] Case Western Reserve Univ, Cleveland, OH 44106 USA

[2] Cleveland Clin, Cleveland, OH 44195 USA

[3] Phycal Inc, Cleveland, OH USA

[4] Ohio State Univ, Columbus, OH 43210 USA

关键词: Algae;    Biofuel;    Magnetic separation;    Ferritin;    Auxenochlorella protothecoides;    Magnetophoresis;   

DOI  :  10.1016/j.jmmm.2014.09.008

来源: Elsevier

【 摘 要 】

Algae were investigated in the past as a potential source of biofuel and other useful chemical derivatives. Magnetic separation of algae by iron oxide nanoparticle binding to cells has been proposed by others for dewatering of cellular mass prior to lipid extraction. We have investigated feasibility of magnetic separation based on the presence of natural iron stores in the cell, such as the ferritin in Auxenochlorella protothecoides (A. protothecoides) strains. The A. protothecoides cell constructs were tested for inserted genes and for increased intracellular iron concentration by inductively coupled plasma atomic absorption (ICP-AA). They were grown in Sueoka's modified high salt media with added vitamin B1 and increasing concentration of soluble iron compound (FeCl3 EDTA, from 1 x to 8 x compared to baseline). The cell magnetic separation conditions were tested using a thin rectangular flow channel pressed against interpolar gaps of a permanent magnet forming a separation system of a well-defined fluid flow and magnetic fringing field geometry (up to 2.2 T and 1000 T/m) dubbed magnetic deposition microscopy, or MDM. The presence of magnetic cells in suspension was detected by formation of characteristic deposition bands at the edges of the magnet interpolar gaps, amenable to optical scanning and microscopic examination. The results demonstrated increasing cellular Fe uptake with increasing Fe concentration in the culture media in wild type strain and in selected genetically-modified constructs, leading to magnetic separation without magnetic particle binding. The throughput in this study is not sufficient for an economical scale harvest. (C) 2014 Published by Elsevier B.V.

【 授权许可】

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