Advances in affinity ligand‐functionalized nanomaterials for biomagnetic separation

Abstract

The downstream processing of proteins remains the most significant cost in protein production, and is largely attributed to rigorous chromatographic purification protocols, where the stringency of purity for biopharmaceutical products sometimes exceeds 99%. With an ever burgeoning biotechnology market, there is a constant demand for alternative purification methodologies, to ameliorate the dependence on chromatography, while still adhering to regulatory concerns over product purity and safety. In this article, we present an up-to-date view of bioseparation, with emphasis on magnetic separation and its potential application in the field. Additionally, we discuss the economic and performance benefits of synthetic ligands, in the form of peptides and miniaturized antibody fragments, compared to full-length antibodies. We propose that adoption of synthetic affinity ligands coupled with magnetic adsorbents, will play an important role in enabling sustainable bioprocessing in the future.

Biopharmaceuticals from microorganisms: from production to purification

“…Each purification step is capable of removing one or more classes of impurities 53, 54. Downstream processing usually encompasses three main stages, namely (i) initial recovery (extraction or isolation), (ii) purification (removal of most contaminants), and (iii) polishing (removal of specified contaminants and unwanted forms of the target biomolecule that may have formed during isolation and purification) 53, 55, 56…”

“…To reach the stringency of purity required in the biopharmaceutical industry, sometimes exceeding 99%, chromatography steps are usually required. Chromatography allows for high resolution and has traditionally been the workhorse for protein purification and polishing 53, 56. However, chromatography has also been the major cost center in purification processes, mainly due to media cost and relatively long cycle times.…”

“…In fact, chromatography is a very effective purification technique with a wide range of industrial applications and currently represents the favorite choice due to its high resolution capacity 56 . The separation principle in chromatography is based on the differences in the affinity of the species carried by a fluid mobile phase toward a solid stationary phase.…”

“…With a burgeoning biotechnology market, there is an ongoing search for new and improved alternatives to chromatography in an effort to lower costs and improve yields, while maintaining high product purity 56 . Several promising alternatives have been described in literature including affinity precipitation, high-performance tangential flow filtration, filtration strategies based on thiophilic and affinity interactions, two-phase aqueous systems, high-gradient magnetic fishing, preparative electrophoresis, and isoelectric focusing 53, 55, 56, 58…”

Bio‐Nano‐Magnetic Materials for Localized Mechanochemical Stimulation of Cell Growth and Death

“…[34] Alternatively, spherical magnetic beads (where magnetic nanocrystals are dispersed within a polymer matrix) 0.1–100 μm in diameter can be used. [42] (Novel emulsion-templated synthesis has been shown to increase the nanocrystal density of the beads such that the saturation magnetization is 6 times higher than commercial beads). [43] In both cases, there exist large selections of chemically modified surfaces, which can be tailored for affinity targeting of specific cells.…”