Monolithic molecularly imprinted cryogel for lysozyme recognition

Abstract

The application of molecularly imprinted polymers in the selective adsorption of macromolecules such as proteins by monolithic protein-imprinted columns requires a macroporous structure, which can be provided by cryogelation at low temperature in which the formation of ice crystals gives a porous structure to the molecularly imprinted polymer. In this study, we applied this technique to synthesize lysozyme-imprinted polyacrylamide cryogels containing 8% w/v of total monomers and 0.3% w/v of lysozyme. The synthesized cryogel was sponge-like and elastic with very fast swelling and reshaping properties, showing a swelling ratio of 24.5 ± 3 and gel fraction yield of about 72%. It showed an imprinting effect of 1.58 and a separation factor of 1.37 for cytochrome c as the competing protein. Adsorption studies on the cryogel revealed that it follows the Langmuir isotherm, with a maximum theoretical adsorption capacity of 36.3 mg lysozyme per gram of cryogel. Additionally, it was shown that a salt-free rebinding solution at low flow rate and pH = 7.0 is favorable for lysozyme rebinding. This kind of monolithic column promises a wide range of application in separation of various biomolecules due to its preparation simplicity, good rebinding characteristics, and macroporosity.

Synthesis of Hydrophobic Polymeric Cryogels with Supermacroporous Structure

“…[ 6 ] Nowadays cryogels have been developed to several formats including monolith, disc, membrane, and bead, which have found many applications in bioseparation, tissue engineering, heavy metal removal, and oil absorbent, among others. [7][8][9][10][11][12][13][14][15][16] Typically, cryogels possess supermacropores that lie normally in the range of several micrometers to several hundred micrometers in pore size, and are linked to form interconnected porous structure…”

Organized cryogel composites with 3D hierarchical porosity as an extraction adsorbent for nucleosides

“…However, the inherent drawbacks of cryogels are scarce functional monomers or crosslinkers with high activity and good water solubility for direct application or functionalization, difficulty in adjusting macropore structure, and the rather low specific surface area, which have been considered as the major challenges to broaden their applications [10]. Presently, most cryogels are used for purification of large biomolecules [11], such as DNA or dehydrogenase, chromatographic separation or capturing of proteins [12], tissue engineering [13], cell culturing [14], and so on. However, some cryogel composites have been exploited by traditional embedding of functional particles during cryogelation or immobilizing them on the pore surface of cryogels [15,16].…”

Poly(ether sulfone) nanoparticles and controllably modified nanoparticles obtained through temperature‐dependent cryogelation

“…Cryogelation was first established for the development of macroporous hydrophilic cryogels with interconnected macropores, and relatively higher mechanical strengths due to the structure of pore walls were formed as a result of the high polymer concentration in the nonfrozen liquid microphase . Recently, their potential for biotechnological applications has been explored, such as in our latest study on protein‐imprinted monolith polymer columns and technologically challenging separation processes, such as cell separation . However, current cryogelation processes cannot be used for the fabrication of nanosized particles because the dissolved solutes (monomers or polymer precursors) are squeezed by ice crystals to connect in the nonfrozen liquid microphase.…”