Construction of a highly efficient adsorbent for one-step purification of recombinant proteins: Functionalized cellulose-based monolith fabricated via phase separation method.

Currently, purification step in the recombinant protein manufacture is still a great challenge and its cost far outweighs those of the upstream process. In this study, a functionalized cellulose-based monolith was constructed as an efficient affinity adsorbent for one-step purification of recombinant proteins. Firstly, the fundamental cellulose monolith (CE monolith) was fabricated based on thermally induced phase separation, followed by being modified with nitrilotriacetic acid anhydride through esterification to give NCE monolith. After chelating with Ni2+, the affinity adsorbent NCE-Ni2+ monolith was obtained, which was demonstrated to possess a hierarchically porous morphology with a relatively high surface area, porosity and compressive strength. The adsorption behavior of NCE-Ni2+ monolith towards ß2-microglobulin with 6 N-terminus His-tag (His-ß2M) was evaluated through batch and fixed-bed column experiments. The results revealed that NCE-Ni2+ monolith exhibited a relatively fast His-ß2M adsorption rate with a maximum adsorption capacity of 329.2 mg/g. The fixed-bed column adsorption implied that NCE-Ni2+ monolith showed high efficiency for His-ß2M adsorption. Finally, NCE-Ni2+ monolith was demonstrated to have an excellent His-ß2M purification ability from E. coli lysate with exceptional reusability. Therefore, the resultant NCE-Ni2+ monolith had large potential to be used as an efficient adsorbent for recombinant protein purification in practical applications.

Dual-modified albumin-polymer nanocomplexes with enhanced in vivo stability for hepatocellular carcinoma therapy.

Etoposide (ETO) is a semi-synthetic derivative of podophyllotoxin with a definite antitumour effect, but its use is hampered by poor solubility and numerous side-effects. In this work, we developed a hyaluronic acid and ethylenediamine dual-modified albumin-polymer nanocomplex for tumour targeted delivery of ETO. The ETO loaded dual-modified albumin-polymer nanocomplexes (E-HEAP NCs) was composed of a hyaluronic acid decorated cationic albumin shell and a stable poly (butyl cyanoacrylate) core. E-HEAP NCs exhibited a high encapsulation efficiency, great stability in vivo. Furthermore, blank HEAP NCs carrier showed excellent biocompatibility in vitro cell cytotoxicity assay. While, E-HEAP NCs represented superior inhibitory effect on HepG2 cells than free ETO. Additionally, E-HEAP NCs exhibited an excellent tumour-targeting effect, due to the enhanced targeting efficacy of hyaluronic acid and albumin-mediated transcytosis. Moreover, E-HEAP NCs displayed an enhanced antitumour effect and extended the survival period in tumour bearing mice. In summary, the developed novel protein-polymer nanocomplex can potentially serve as a drug delivery system for improved cancer therapy.

A hierarchically porous cellulose monolith: A template-free fabricated, morphology-tunable, and easily functionalizable platform.

Recently, monoliths with continuous porous structure have received much attention for high-performance separation/adsorption matrix in biomedical and environmental fields. This study proposes a novel route to prepare cellulose monoliths with hierarchically porous structure by selecting cellulose acetate (CA) as the starting material. Thermally induced phase separation of CA solution using a mixed solvent affords a CA monolith, which is converted into the cellulose monolith by alkaline hydrolysis. Scanning electron microscopy images of the CA and cellulose monoliths reveal a continuous macropore with rough surface, and nitrogen adsorption/desorption analysis indicates the formation of a mesoporous structure. The macroporous structure could be controlled by changing the fabrication parameters. A series of reactive groups are introduced by chemical modifications on the surface of the cellulose monolith. The facile and diverse modifiability combined with its hydrophilic property make the hierarchically porous cellulose monolith a potential platform for use in separation, purification and bio-related applications.

Facile fabrication of mesoporous poly(ethylene-co-vinyl alcohol)/chitosan blend monoliths.

Poly(ethylene-co-vinyl alcohol) (EVOH)/chitosan blend monoliths were fabricated by thermally-induced phase separation method. Chitosan was successfully incorporated into the polymeric monolith by selecting EVOH as the main component of the monolith. SEM images exhibit that the chitosan was located on the inner surface of the monolith. Fourier-transform infrared analysis and elemental analysis indicate the successful blend of EVOH and chitosan. BET results show that the blend monoliths had high specific surface area and uniform mesopore structure. Good adsorption ability toward various heavy metal ions was found in the blend monoliths due to the large chelation capacity of chitosan. The blend monoliths have potential application for waste water purification or bio-related applications.